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Perrone M, Guidetti M, Galli M, Nho SJ, Wimmer MA, Malloy P. Hip joint contact forces are lower in people with femoroacetabular impingement syndrome during squat tasks. J Orthop Res 2024; 42:1045-1053. [PMID: 38032092 DOI: 10.1002/jor.25744] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/16/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023]
Abstract
It remains unknown if hip joint forces during squat tasks are altered in people with femoroacetabular impingement syndrome (FAIS). The aim of this study is to compare hip joint forces between people with FAIS and healthy controls during double leg squat and single leg squat tasks and within limbs during a single leg squat task in people with FAIS. Kinematic and kinetic data were collected in eight people with FAIS and eight healthy matched controls using 3D motion capture and force plates. AnyBody Modeling System was used to perform musculoskeletal simulations to estimate hip joint angles, forces, and moments for all participants. Estimates were postprocessed with AnyPyTools and converted into normalized time series to be compared using a 1D statistical nonparametric mapping (SnPM) approach. SnPM with an independent samples t-test model was used to compare people with FAIS to controls, while a paired samples model was used to compare involved to uninvolved limb in people with FAIS. Patients demonstrated lower proximodistal force compared to controls (p < 0.01) and compared to the uninvolved side (p = 0.01) for single leg squat. The smaller joint contact forces in people with FAIS compared to controls could represent a strategy of reduced muscle forces to avoid pain and symptoms during this high demand task. These findings when combined with imaging data could help assess the severity of FAIS on hip related function during higher demand tasks.
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Affiliation(s)
- Mattia Perrone
- Department of Physical Therapy, Arcadia University, Glenside, Pennsylvania, USA
- Department of Orthopedic Surgery, Division of Sports Medicine, Young Adult Hip Surgery Program, Rush University Medical Center, Chicago, Illinois, USA
- Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, Illinois, USA
- Department of Electronics, Information and Bioengineering, Politecnico Di Milano, Milan, Italy
| | - Martina Guidetti
- Department of Orthopedic Surgery, Division of Sports Medicine, Young Adult Hip Surgery Program, Rush University Medical Center, Chicago, Illinois, USA
| | - Manuela Galli
- Department of Electronics, Information and Bioengineering, Politecnico Di Milano, Milan, Italy
| | - Shane J Nho
- Department of Orthopedic Surgery, Division of Sports Medicine, Young Adult Hip Surgery Program, Rush University Medical Center, Chicago, Illinois, USA
| | - Markus A Wimmer
- Department of Orthopedic Surgery, Division of Sports Medicine, Young Adult Hip Surgery Program, Rush University Medical Center, Chicago, Illinois, USA
- Department of Biomedical Engineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Philip Malloy
- Department of Physical Therapy, Arcadia University, Glenside, Pennsylvania, USA
- Department of Orthopedic Surgery, Division of Sports Medicine, Young Adult Hip Surgery Program, Rush University Medical Center, Chicago, Illinois, USA
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2
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Bhatia A, Hanna J, Stuart T, Kasper KA, Clausen DM, Gutruf P. Wireless Battery-free and Fully Implantable Organ Interfaces. Chem Rev 2024; 124:2205-2280. [PMID: 38382030 DOI: 10.1021/acs.chemrev.3c00425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Advances in soft materials, miniaturized electronics, sensors, stimulators, radios, and battery-free power supplies are resulting in a new generation of fully implantable organ interfaces that leverage volumetric reduction and soft mechanics by eliminating electrochemical power storage. This device class offers the ability to provide high-fidelity readouts of physiological processes, enables stimulation, and allows control over organs to realize new therapeutic and diagnostic paradigms. Driven by seamless integration with connected infrastructure, these devices enable personalized digital medicine. Key to advances are carefully designed material, electrophysical, electrochemical, and electromagnetic systems that form implantables with mechanical properties closely matched to the target organ to deliver functionality that supports high-fidelity sensors and stimulators. The elimination of electrochemical power supplies enables control over device operation, anywhere from acute, to lifetimes matching the target subject with physical dimensions that supports imperceptible operation. This review provides a comprehensive overview of the basic building blocks of battery-free organ interfaces and related topics such as implantation, delivery, sterilization, and user acceptance. State of the art examples categorized by organ system and an outlook of interconnection and advanced strategies for computation leveraging the consistent power influx to elevate functionality of this device class over current battery-powered strategies is highlighted.
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Affiliation(s)
- Aman Bhatia
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Jessica Hanna
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Tucker Stuart
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Kevin Albert Kasper
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - David Marshall Clausen
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
| | - Philipp Gutruf
- Department of Biomedical Engineering, The University of Arizona, Tucson, Arizona 85721, United States
- Department of Electrical and Computer Engineering, The University of Arizona, Tucson, Arizona 85721, United States
- Bio5 Institute, The University of Arizona, Tucson, Arizona 85721, United States
- Neuroscience Graduate Interdisciplinary Program (GIDP), The University of Arizona, Tucson, Arizona 85721, United States
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3
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Brandl C, Bender A, Schmachtenberg T, Dymke J, Damm P. Comparing risk assessment methods for work-related musculoskeletal disorders with in vivo joint loads during manual materials handling. Sci Rep 2024; 14:6041. [PMID: 38472286 PMCID: PMC10933320 DOI: 10.1038/s41598-024-56580-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 03/08/2024] [Indexed: 03/14/2024] Open
Abstract
The validity of observational methods in ergonomics is still challenging research. Criterion validity in terms of concurrent validity is the most commonly studied. However, studies comparing observational methods with biomechanical values are rare. Thus, the aim of this study is to compare the Ovako Working Posture Analysing System (OWAS) and the Rapid Entire Body Assessment (REBA) with in vivo load measurements at hip, spine, and knee during stoop and squat lifting of 14 participants. The results reveal that OWAS and REBA action levels (AL) can distinguish between different in vivo load measurements during manual lifting. However, the results also reveal that the same OWAS- and REBA-AL do not necessarily provide equal mean values of in vivo load measurements. For example, resultant contact force in the vertebral body replacement for squat lifting ranged from 57% body weight (%BW) in OWAS-AL1 to 138%BW in OWAS-AL3 compared to 46%BW in REBA-AL0 and 173%BW in REBA-AL3. Furthermore, the results suggest that the performed squat lifting techniques had a higher risk for work-related musculoskeletal disorders than the performed stoop lifting techniques.
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Affiliation(s)
- Christopher Brandl
- Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Eilfschornsteinstr. 27, 52062, Aachen, Germany.
- Fraunhofer Institute for Communication, Information Processing and Ergonomics FKIE, Aachen, Germany.
| | - Alwina Bender
- Julius Wolff Institute of Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tim Schmachtenberg
- Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Eilfschornsteinstr. 27, 52062, Aachen, Germany
| | - Jörn Dymke
- Julius Wolff Institute of Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute of Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
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4
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Crisco JJ, Henke JA, McDermott DG, Badida R, Morton AM, Kalshoven JM, Moore DC. Development of an implantable trapezium carpal bone replacement for measuring in vivo loads at the base of the thumb. J Biomech 2024; 165:112013. [PMID: 38401330 PMCID: PMC10956735 DOI: 10.1016/j.jbiomech.2024.112013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 01/22/2024] [Accepted: 02/19/2024] [Indexed: 02/26/2024]
Abstract
Understanding the loads that occur across musculoskeletal joints is critical to advancing our understanding of joint function and pathology, implant design and testing, as well as model verification. Substantial work in these areas has occurred in the hip and knee but has not yet been undertaken in smaller joints, such as those in the wrist. The thumb carpometacarpal (CMC) joint is a uniquely human articulation that is also a common site of osteoarthritis with unknown etiology. We present two potential designs for an instrumented trapezium implant and compare approaches to load calibration. Two instrumented trapezia designs were prototyped using strain gauge technology: Tube and Diaphragm. The Tube design is a well-established structure for sensing loads while the Diaphragm is novel. Each design was affixed to a 6-DOF load cell that was used as the reference. Loads were applied manually, and two calibration methods, supervised neural network (DEEP) and matrix algebra (MAT), were implemented. Bland-Altman 95% confidence interval for the limits of agreement (95% CI LOA) was used to assess accuracy. Overall, the DEEP calibration decreased 95% CI LOA compared with the MAT approach for both designs. The Diaphragm design outperformed the Tube design in measuring the primary load vector (joint compression). Importantly, the Diaphragm design permits the hermetic encapsulation of all electronics, which is not possible with the Tube design, given the small size of the trapezium. Substantial work remains before this device can be approved for implantation, but this work lays the foundation for further device development that will be required.
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Affiliation(s)
- Joseph J Crisco
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States.
| | - Julia A Henke
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
| | - Daniel G McDermott
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
| | - Rohit Badida
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
| | - Amy M Morton
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
| | - Josephine M Kalshoven
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
| | - Douglas C Moore
- Department of Orthopaedics, Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI, United States
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Wang J, Chu J, Song J, Li Z. The application of impantable sensors in the musculoskeletal system: a review. Front Bioeng Biotechnol 2024; 12:1270237. [PMID: 38328442 PMCID: PMC10847584 DOI: 10.3389/fbioe.2024.1270237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 01/08/2024] [Indexed: 02/09/2024] Open
Abstract
As the population ages and the incidence of traumatic events rises, there is a growing trend toward the implantation of devices to replace damaged or degenerated tissues in the body. In orthopedic applications, some implants are equipped with sensors to measure internal data and monitor the status of the implant. In recent years, several multi-functional implants have been developed that the clinician can externally control using a smart device. Experts anticipate that these versatile implants could pave the way for the next-generation of technological advancements. This paper provides an introduction to implantable sensors and is structured into three parts. The first section categorizes existing implantable sensors based on their working principles and provides detailed illustrations with examples. The second section introduces the most common materials used in implantable sensors, divided into rigid and flexible materials according to their properties. The third section is the focal point of this article, with implantable orthopedic sensors being classified as joint, spine, or fracture, based on different practical scenarios. The aim of this review is to introduce various implantable orthopedic sensors, compare their different characteristics, and outline the future direction of their development and application.
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Affiliation(s)
- Jinzuo Wang
- Department of Orthopaedics, First Affiliated Hospital of Dalian Medical University, Dalian, China
- Key Laboratory of Molecular Mechanism for Repair and Remodeling of Orthopaedic Diseases, Dalian, Liaoning, China
| | - Jian Chu
- Department of Engineering Mechanics, Dalian University of Technology, Dalian, China
| | - Jinhui Song
- Department of Engineering Mechanics, Dalian University of Technology, Dalian, China
| | - Zhonghai Li
- Department of Orthopaedics, First Affiliated Hospital of Dalian Medical University, Dalian, China
- Key Laboratory of Molecular Mechanism for Repair and Remodeling of Orthopaedic Diseases, Dalian, Liaoning, China
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Bender A, Schmidt H, Wellner DL, Duda GN, Brandl C, Damm P. In vivo load on knee, hip and spine during manual materials handling with two lifting techniques. J Biomech 2024; 163:111963. [PMID: 38286711 DOI: 10.1016/j.jbiomech.2024.111963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 01/31/2024]
Abstract
It is generally accepted that the lifting technique strongly influences physical loads within the human body and, thus, the risk of musculoskeletal disorders. However, there is a lack of knowledge regarding whether particular lifting techniques are effective in reducing loads. Hence, this retrospective study quantified (partly published) in vivo loads at joints within the human body during two typical lifting techniques, stoop lifting and squat lifting. Patients who had received instrumented implants underwent in vivo load measurements at either the knee (two patients), the hip (eight patients), or the upper lumbar spine (four patients) while lifting a 10 kg weight frontally with either straight (stoop) or bent (squat) knees. Contact forces and moments and the orientation of the contact force vector were determined and examined using the paired t test of Statistical Parametric Mapping. The two lifting techniques did not differ in terms of load magnitudes but did differ in terms of directions: (i) at the hip joint, the load vector varied significantly (p < 0.05) in the frontal and sagittal planes, (ii) at the knee joint, the load vector differed significantly (p < 0.05) in the sagittal plane (iii) while the load vector and magnitude did not differ at the upper lumbar spine (p > 0.05). Our findings indicate that the lifting technique causes changes in the orientation rather than the magnitude of lower extremity joint contact loads. Even though this quantification could only be performed in a small group of patients, the quantification of the relevance of such lifting technique recommendations will hopefully guide future recommendations towards a more scientific interpretation.
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Affiliation(s)
- Alwina Bender
- Julius Wolff Institute, Berlin Institute of Health at Charité, Charité - Universitätsmedizin Berlin, Germany
| | - Hendrik Schmidt
- Julius Wolff Institute, Berlin Institute of Health at Charité, Charité - Universitätsmedizin Berlin, Germany
| | - Daniela L Wellner
- Julius Wolff Institute, Berlin Institute of Health at Charité, Charité - Universitätsmedizin Berlin, Germany
| | - Georg N Duda
- Julius Wolff Institute, Berlin Institute of Health at Charité, Charité - Universitätsmedizin Berlin, Germany
| | - Christopher Brandl
- Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Aachen, Germany; Fraunhofer Institute for Communication, Information Processing and Ergonomics FKIE, Aachen, Germany
| | - Philipp Damm
- Julius Wolff Institute, Berlin Institute of Health at Charité, Charité - Universitätsmedizin Berlin, Germany.
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7
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Zhou S, Bender A, Kutzner I, Dymke J, Maleitzke T, Perka C, Duda GN, Winkler T, Damm P. Loading of the Hip and Knee During Swimming: An in Vivo Load Study. J Bone Joint Surg Am 2023; 105:1962-1971. [PMID: 38079507 DOI: 10.2106/jbjs.23.00218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
BACKGROUND Swimming is commonly recommended as postoperative rehabilitation following total hip arthroplasty (THA) and total knee arthroplasty (TKA). So far, in vivo hip and knee joint loads during swimming remain undescribed. METHODS In vivo hip and knee joint loads were measured in 6 patients who underwent THA and 5 patients who underwent TKA with instrumented joint implants. Joint loads, including the resultant joint contact force (F Res ), torsional moment around the femoral shaft axis or the tibial axis (M Tors ), bending moment at the middle of the femoral neck (M Bend ), torsional moment around the femoral neck axis (M Tne ), and medial force ratio (MFR) in the knee, were measured during breaststroke swimming at 0.5, 0.6, and 0.7 m/s and the breaststroke and crawl kicks at 0.5 and 1.0 m/s. RESULTS The ranges of the median maximal F Res were 157% to 193% of body weight for the hip and 93% to 145% of body weight for the knee during breaststroke swimming. Greater maxima of F Res (hip and knee), M Tors (hip and knee), M Bend (hip), and M Tne (hip) were observed with higher breaststroke swimming velocities, but significance was only identified between 0.5 and 0.6 m/s in F Res (p = 0.028), M Tors (p = 0.028), and M Bend (p = 0.028) and between 0.5 and 0.7 m/s in F Res (p = 0.045) in hips. No difference was found in maximal MFR between different breaststroke swimming velocities. The maximal F Res was significantly positively correlated with the breaststroke swimming velocity (hip: r = 0.541; p < 0.05; and knee: r = 0.414; p < 0.001). The maximal F Res (hip and knee) and moments (hip) were higher in the crawl kick than in the breaststroke kick, and a significant difference was recognized in F Res Max for the hip: median, 179% versus 118% of body weight (p = 0.028) for 0.5 m/s and 166% versus 133% of body weight (p = 0.028) for 1.0 m/s. CONCLUSIONS Swimming is a safe and low-impact activity, particularly recommended for patients who undergo THA or TKA. Hip and knee joint loads are greater with higher swimming velocities and can be influenced by swimming styles. Nevertheless, concrete suggestions to patients who undergo arthroplasty on swimming should involve individual considerations. LEVEL OF EVIDENCE Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Sijia Zhou
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Brandenburg Center for Regenerative Therapies, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Alwina Bender
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ines Kutzner
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jörn Dymke
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tazio Maleitzke
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health Charité Clinician Scientist Program, BIH Biomedical Innovation Academy, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Carsten Perka
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Georg N Duda
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Brandenburg Center for Regenerative Therapies, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tobias Winkler
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin Brandenburg Center for Regenerative Therapies, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Berlin, Germany
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Zdero R, Brzozowski P, Schemitsch EH. Experimental Methods for Studying the Contact Mechanics of Joints. BIOMED RESEARCH INTERNATIONAL 2023; 2023:4914082. [PMID: 37780487 PMCID: PMC10541306 DOI: 10.1155/2023/4914082] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 09/07/2023] [Accepted: 09/12/2023] [Indexed: 10/03/2023]
Abstract
Biomechanics researchers often experimentally measure static or fluctuating dynamic contact forces, areas, and stresses at the interface of natural and artificial joints, including the shoulders, elbows, hips, and knees. This information helps explain joint contact mechanics, as well as mechanisms that may contribute to disease, damage, and degradation. Currently, the most common in vitro experimental technique involves a thin pressure-sensitive film inserted into the joint space; but, the film's finite thickness disturbs the joint's ordinary articulation. Similarly, the most common in vivo experimental technique uses video recording of 3D limb motion combined with dynamic analysis of a 3D link-segment model to calculate joint contact force, but this does not provide joint contact area or stress distribution. Moreover, many researchers may be unaware of older or newer alternative techniques that may be more suitable for their particular research application. Thus, this article surveys over 50 years of English-language scientific literature in order to (a) describe the basic working principles, advantages, and disadvantages of each technique, (b) examine the trends among the studies and methods, and (c) make recommendations for future directions. This article will hopefully inform biomechanics investigators about various in vitro and in vivo experimental methods for studying the contact mechanics of joints.
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Affiliation(s)
- Radovan Zdero
- Orthopaedic Biomechanics Lab, Victoria Hospital, London, Canada
| | | | - Emil H. Schemitsch
- Orthopaedic Biomechanics Lab, Victoria Hospital, London, Canada
- Division of Orthopaedic Surgery, Western University, London, Canada
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Shuttleworth MP, Vickers O, Smeeton M, Board T, Isaac G, Culmer P, Williams S, Kay RW. Inertial Tracking System for Monitoring Dual Mobility Hip Implants In Vitro. SENSORS (BASEL, SWITZERLAND) 2023; 23:s23020904. [PMID: 36679702 PMCID: PMC9863608 DOI: 10.3390/s23020904] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/05/2023] [Accepted: 01/10/2023] [Indexed: 06/12/2023]
Abstract
Dual mobility (DM) implants are being increasingly used for total hip arthroplasties due to the additional range of motion and joint stability they afford over more traditional implant types. Currently, there are no reported methods for monitoring their motions under realistic operating conditions while in vitro and, therefore, it is challenging to predict how they will function under clinically relevant conditions and what failure modes may exist. This study reports the development, calibration, and validation of a novel inertial tracking system that directly mounts to the mobile liner of DM implants. The tracker was custom built and based on a miniaturized, off-the-shelf inertial measurement unit (IMU) and employed a gradient-decent sensor fusion algorithm for amalgamating nine degree-of-freedom IMU readings into three-axis orientation estimates. Additionally, a novel approach to magnetic interference mitigation using a fixed solenoid and magnetic field simulation was evaluated. The system produced orientation measurements to within 1.0° of the true value under ideal conditions and 3.9° with a negligible drift while in vitro, submerged in lubricant, and without a line of sight.
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Affiliation(s)
| | - Oliver Vickers
- Institute of Medical and Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Mackenzie Smeeton
- Institute of Medical and Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Tim Board
- Institute of Medical and Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
- Wrightington, Wigan & Leigh NHS Foundation Trust, Wigan WN6 9EP, UK
| | - Graham Isaac
- Institute of Medical and Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Peter Culmer
- Healthcare Mechatronics, University of Leeds, Leeds LS2 9JT, UK
| | - Sophie Williams
- Institute of Medical and Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Robert William Kay
- Future Manufacturing Processes Research Group, University of Leeds, Leeds LS2 9JT, UK
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10
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Tomasi M, Artoni A, Mattei L, Di Puccio F. On the estimation of hip joint loads through musculoskeletal modeling. Biomech Model Mechanobiol 2022; 22:379-400. [PMID: 36571624 DOI: 10.1007/s10237-022-01668-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 12/04/2022] [Indexed: 12/27/2022]
Abstract
Noninvasive estimation of joint loads is still an open challenge in biomechanics. Although musculoskeletal modeling represents a solid resource, multiple improvements are still necessary to obtain accurate predictions of joint loads and to translate such potential into practical utility. The present study, focused on the hip joint, is aimed at reviewing the state-of-the-art literature on the estimation of hip joint reaction forces through musculoskeletal modeling. Our literature inspection, based on well-defined selection criteria, returned seventeen works, which were compared in terms of methods and results. Deviations between predicted and in vivo measured hip joint loads, taken from the OrthoLoad database, were assessed through quantitative deviation indices. Despite the numerous modeling and computational improvements made over the last two decades, predicted hip joint loads still deviate from their experimental counterparts and typically overestimate them. Several critical aspects have emerged that affect muscle force estimation, hence joint loads. Among them, the physical fidelity of the musculoskeletal model, with its parameters and geometry, plays a crucial role. Also, predicted joint loads are markedly affected by the selected muscle recruitment strategy, which reflects the underlying motor control policy. Practical guidelines for researchers interested in noninvasive estimation of hip joint loads are also provided.
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Affiliation(s)
- Matilde Tomasi
- Department of Civil and Industrial Engineering, Università di Pisa, Pisa, Italy
| | - Alessio Artoni
- Department of Civil and Industrial Engineering, Università di Pisa, Pisa, Italy
| | - Lorenza Mattei
- Department of Civil and Industrial Engineering, Università di Pisa, Pisa, Italy.,Sport and Anatomy Centre, Università di Pisa, Pisa, Italy
| | - Francesca Di Puccio
- Department of Civil and Industrial Engineering, Università di Pisa, Pisa, Italy. .,Sport and Anatomy Centre, Università di Pisa, Pisa, Italy.
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11
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Ledet EH, Caparaso SM, Stout M, Cole KP, Liddle B, Cady NC, Archdeacon MT. Smart fracture plate for quantifying fracture healing: Preliminary efficacy in a biomechanical model. J Orthop Res 2022; 40:2414-2420. [PMID: 34989023 DOI: 10.1002/jor.25254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 10/31/2021] [Accepted: 12/19/2021] [Indexed: 02/04/2023]
Abstract
The diagnosis of fracture nonunion following plate osteosynthesis is subjective and frequently ambiguous. Initially following osteosynthesis, loads applied to the bone are primarily transmitted through the plate. However, as callus stiffness increases, the callus is able to bear load proportional to its stiffness while forces through the plate decrease. The purpose of this study was to use a "smart" fracture plate to distinguish between phases of fracture healing by measuring forces transmitted through the plate. A wireless force sensor and small adapter were placed on the outside of a distal femoral locking plate. The adapter converts the slight bending of the plate under axial load into a transverse force which is measurable by the sensor. An osteotomy was created and then plated in the distal femur of biomechanical Sawbones. Specimens were loaded to simulate single-leg stance first with the osteotomy defect empty (acute healing), then sequentially filled with silicone (early callus) and then polymethyl methacrylate (hard callus). There was a strong correlation between applied axial load and force measured by the "smart" plate. Data demonstrate statistically significant differences between each phase of healing with as little as 150 N of axial load applied to the femur. Forces measured in the plate were significantly different between acute (100%), early callus (66.4%), and hard callus (29.5%). This study demonstrates the potential of a "smart" fracture plate to distinguish between phases of healing. These objective data may enable early diagnosis of nonunion and enhance outcomes for patients.
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Affiliation(s)
- Eric H Ledet
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute & Research and Development Service, Stratton VA Medical Center, Albany, New York, USA
| | - Sydney M Caparaso
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Madelyn Stout
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Keegan P Cole
- Division of Orthopaedic Surgery, Albany Medical College, Albany, New York, USA
| | - Benjamin Liddle
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, New York, USA
| | - Nathaniel C Cady
- Department of Nanobio Science, State University of New York Polytechnic Institute, Utica, New York, USA
| | - Michael T Archdeacon
- Department of Orthopaedic Surgery, University of Cincinnati Medical Center, Cincinnati, Ohio, USA
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12
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Veletić M, Apu EH, Simić M, Bergsland J, Balasingham I, Contag CH, Ashammakhi N. Implants with Sensing Capabilities. Chem Rev 2022; 122:16329-16363. [PMID: 35981266 DOI: 10.1021/acs.chemrev.2c00005] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Because of the aging human population and increased numbers of surgical procedures being performed, there is a growing number of biomedical devices being implanted each year. Although the benefits of implants are significant, there are risks to having foreign materials in the body that may lead to complications that may remain undetectable until a time at which the damage done becomes irreversible. To address this challenge, advances in implantable sensors may enable early detection of even minor changes in the implants or the surrounding tissues and provide early cues for intervention. Therefore, integrating sensors with implants will enable real-time monitoring and lead to improvements in implant function. Sensor integration has been mostly applied to cardiovascular, neural, and orthopedic implants, and advances in combined implant-sensor devices have been significant, yet there are needs still to be addressed. Sensor-integrating implants are still in their infancy; however, some have already made it to the clinic. With an interdisciplinary approach, these sensor-integrating devices will become more efficient, providing clear paths to clinical translation in the future.
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Affiliation(s)
- Mladen Veletić
- Department of Electronic Systems, Norwegian University of Science and Technology, 7491 Trondheim, Norway.,The Intervention Centre, Technology and Innovation Clinic, Oslo University Hospital, 0372 Oslo, Norway
| | - Ehsanul Hoque Apu
- Institute for Quantitative Health Science and Engineering (IQ) and Department of Biomedical Engineering (BME), Michigan State University, East Lansing, Michigan 48824, United States.,Division of Hematology and Oncology, Department of Internal Medicine, Michigan Medicine, University of Michigan, Ann Arbor, Michigan 48105, United States
| | - Mitar Simić
- Faculty of Electrical Engineering, University of Banja Luka, 78000 Banja Luka, Bosnia and Herzegovina
| | - Jacob Bergsland
- The Intervention Centre, Technology and Innovation Clinic, Oslo University Hospital, 0372 Oslo, Norway
| | - Ilangko Balasingham
- Department of Electronic Systems, Norwegian University of Science and Technology, 7491 Trondheim, Norway.,The Intervention Centre, Technology and Innovation Clinic, Oslo University Hospital, 0372 Oslo, Norway
| | - Christopher H Contag
- Institute for Quantitative Health Science and Engineering (IQ) and Department of Biomedical Engineering (BME), Michigan State University, East Lansing, Michigan 48824, United States
| | - Nureddin Ashammakhi
- Institute for Quantitative Health Science and Engineering (IQ) and Department of Biomedical Engineering (BME), Michigan State University, East Lansing, Michigan 48824, United States.,Department of Bioengineering, University of California, Los Angeles, California 90095, United States
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13
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Ground reaction forces and external hip joint moments predict in vivo hip contact forces during gait. J Biomech 2022; 135:111037. [DOI: 10.1016/j.jbiomech.2022.111037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/21/2022] [Accepted: 03/09/2022] [Indexed: 11/23/2022]
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14
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Haffer H, Bender A, Krump A, Hardt S, Winkler T, Damm P. Is Training With Gym Machines Safe After Hip Arthroplasty?—An In Vivo Load Investigation. Front Bioeng Biotechnol 2022; 10:857682. [PMID: 35402408 PMCID: PMC8989469 DOI: 10.3389/fbioe.2022.857682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 02/07/2022] [Indexed: 12/12/2022] Open
Abstract
Background: Training with gym machines is one of the most popular physical activities after total hip arthroplasty (THA). However, to date, there are no evidence-based recommendations for physical activity after THA, worldwide. The aim of the study is to evaluate the in vivo hip joint loads during exercises on four widely used gym machines in order to provide a source for an evidence-based patient counselling for arthroplasty surgeons. Methods: The in vivo hip joint loads in seven patients (59.6 ± 6.4 years, 28.6 ± 2.1 kg/m2) with instrumented hip implants were assessed. The resulting force (Fres), bending moment (Mbend), and torsional moment (Mtors) were evaluated during the training on leg curl/leg extension machines (loads: 20, 30, and 40 kg), leg press machine [backrest: 10°, 30°, and 60°; load: 50, 75, and 100%BW (bodyweight)], and a rope pull machine (abduction/adduction/flexion/extension; each ipsi- and contralateral; load 10 kg). These loads were compared with the loads during walking on treadmill at 4 km/h (median peak values: Fres 303%BW, Mbend 4.25%BWm, and Mtors 2.70%BWm). Results: In each of the four performed exercises with a total of 23 different load conditions or exercise modes analyzed, a significantly lower or not different load was detected with respect to Fres, Mbend, and Mtors measured while walking with 4 km/h. Nevertheless, Fres and Mbend demonstrated a trend to increased loading during the ipsilateral monopod standing rope pull exercises hip flexion, extension, and abduction. Conclusion: Based on our investigation, we assume that the investigated gym machines and external loads can be considered mainly as low-impact sports (with some exceptions) and thus as safe physical activity after THA. Due to the fact that the examinations were conducted in the mean 17.4 months after THA, the applicability of the results to the immediate postoperative period is limited.
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Affiliation(s)
- Henryk Haffer
- Center for Musculoskeletal Surgery Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Alwina Bender
- Julius Wolff Institute, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Alexander Krump
- Julius Wolff Institute, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sebastian Hardt
- Center for Musculoskeletal Surgery Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Tobias Winkler
- Center for Musculoskeletal Surgery Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- Julius Wolff Institute, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
- *Correspondence: Philipp Damm,
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15
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Bender A, Damm P, Hommel H, Duda GN. Overstretching Expectations May Endanger the Success of the “Millennium Surgery”. Front Bioeng Biotechnol 2022; 10:789629. [PMID: 35237570 PMCID: PMC8882767 DOI: 10.3389/fbioe.2022.789629] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/07/2022] [Indexed: 11/13/2022] Open
Abstract
Total hip arthroplasty (THA) is an extremely successful treatment strategy. Patient expectations, however, have increased; if not properly guided by surgeons, at present, patients expect next to pain-free restoration of the joint and a fast return to work and sports. While the revision rates after THA also increased in younger patients, knowledge on musculoskeletal loads still remains sparse, and the current recommendations on postoperative rehabilitation are based on expert opinions only. The aim of this study was to unravel biomechanical contact conditions in “working age” (<60 years, 53.5 ± 3.0 years) and “retirement age” (>60 years, 67.7 ± 8.6 years) patients during activities recommended post-THA. We hypothesized that working age patients would show substantially increased hip contact loads compared to older patients. The in vivo joint contact force (Fres) and torsion torque (Mtors), reflecting the main contact load situation, experienced during activities of daily living and sports activities were measured in a unique group of 16 patients with instrumented THA. We summarized patient activities and sports recommendations after THA mentioned within the literature using PubMed (without claim of completeness). The measurements showed that younger working age patients experienced significant (p = 0.050) increased Mtors (21.52 ± 9.11 Nm) than older retirement age patients (13.99 ± 7.89 Nm) by walking. Bowling, as a recommended low-impact sport, was associated with Fres of up to 5436 N and Mtors of up to 108 Nm in the working age group, which were higher than the Fres (5276 N) and Mtors (71 Nm) during high-impact soccer. Based on our results, age was proven to be a discriminator in joint loading, with working age patients presenting with increased loads compared to retirement age patients, already during daily activities. The current patient recommendations have led to further increased joint loadings. If THA cannot be delayed in a patient, we propose counselling patients on a carefully considered return to sports, focusing on low-impact activities, as indicated hereby. The findings from this work illustrate the need to provide critical feedback to patient expectations when returning to work and sports activities. Patients returning to more intensive sports activities should be carefully monitored and advised to avoid as much overloading as possible.
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Affiliation(s)
- Alwina Bender
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius-Wolff-Institute, Berlin, Germany
| | - Philipp Damm
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius-Wolff-Institute, Berlin, Germany
- *Correspondence: Philipp Damm,
| | - Hagen Hommel
- Department of Orthopaedics, Märkisch-Oderland Hospital, Brandenburg Medical School Theodor Fontane, Wriezen, Germany
| | - Georg N. Duda
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius-Wolff-Institute, Berlin, Germany
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16
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Maquer G, Favre P. [Enriching in vivo clinical trials with in silico models for orthopedic implants]. Med Sci (Paris) 2022; 38:38-44. [PMID: 35060885 DOI: 10.1051/medsci/2021243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Clinical trials are used by the medical device industry to confirm products safety, performance, and clinical benefits. Traditional clinical studies typically follow a limited number of volunteers, which prevents capturing the full breath of patient demographics and implant use. New tools are required to overcome the limitations of traditional trials while fulfilling increasingly demanding regulatory requirements. Computer simulations have the potential to enrich traditional clinical trials with so called in silico clinical trials (ISCT) by providing data on a much broader spectrum of patients, clinical conditions and implant configurations. The historical use of simulation in the orthopedic device industry is described here to explain how it is now technically possible to model virtual populations. We also discuss the multiple benefits of such a translational research approach for the patients, healthcare systems, and manufacturers, but also the challenges to overcome. A more detailed version is available in English [1].
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17
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de Sousa BM, Correia CR, Ferreira JAF, Mano JF, Furlani EP, Soares Dos Santos MP, Vieira SI. Capacitive interdigitated system of high osteoinductive/conductive performance for personalized acting-sensing implants. NPJ Regen Med 2021; 6:80. [PMID: 34815414 PMCID: PMC8611088 DOI: 10.1038/s41536-021-00184-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 10/19/2021] [Indexed: 11/15/2022] Open
Abstract
Replacement orthopedic surgeries are among the most common surgeries worldwide, but clinically used passive implants cannot prevent failure rates and inherent revision arthroplasties. Optimized non-instrumented implants, resorting to preclinically tested bioactive coatings, improve initial osseointegration but lack long-term personalized actuation on the bone-implant interface. Novel bioelectronic devices comprising biophysical stimulators and sensing systems are thus emerging, aiming for long-term control of peri-implant bone growth through biointerface monitoring. These acting-sensing dual systems require high frequency (HF) operations able to stimulate osteoinduction/osteoconduction, including matrix maturation and mineralization. A sensing-compatible capacitive stimulator of thin interdigitated electrodes and delivering an electrical 60 kHz HF stimulation, 30 min/day, is here shown to promote osteoconduction in pre-osteoblasts and osteoinduction in human adipose-derived mesenchymal stem cells (hASCs). HF stimulation through this capacitive interdigitated system had significant effects on osteoblasts' collagen-I synthesis, matrix, and mineral deposition. A proteomic analysis of microvesicles released from electrically-stimulated osteoblasts revealed regulation of osteodifferentiation and mineralization-related proteins (e.g. Tgfb3, Ttyh3, Itih1, Aldh1a1). Proteomics data are available via ProteomeXchange with the identifier PXD028551. Further, under HF stimulation, hASCs exhibited higher osteogenic commitment and enhanced hydroxyapatite deposition. These promising osteoinductive/conductive capacitive stimulators will integrate novel bioelectronic implants able to monitor the bone-implant interface and deliver personalized stimulation to peri-implant tissues.
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Affiliation(s)
- Bárbara M de Sousa
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, 3810-193, Aveiro, Portugal
| | - Clara R Correia
- Department of Chemistry, CICECO - Aveiro Institute of Materials, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Jorge A F Ferreira
- Department of Mechanical Engineering, Centre for Mechanical Technology & Automation (TEMA), University of Aveiro, 3810-193, Aveiro, Portugal
| | - João F Mano
- Department of Chemistry, CICECO - Aveiro Institute of Materials, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Edward P Furlani
- Department of Chemical and Biological Engineering, Department of Electrical Engineering, University at Buffalo (SUNY), Buffalo, NY, 14260, USA
| | - Marco P Soares Dos Santos
- Department of Mechanical Engineering, Centre for Mechanical Technology & Automation (TEMA), University of Aveiro, 3810-193, Aveiro, Portugal.
- Faculty of Engineering, Associated Laboratory for Energy, Transports and Aeronautics (LAETA), University of Porto, 4200-465, Porto, Portugal.
| | - Sandra I Vieira
- Department of Medical Sciences, Institute of Biomedicine (iBiMED), University of Aveiro, 3810-193, Aveiro, Portugal.
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18
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Leinauer EC, Kim HM, Kwon JW. Micromachined Tactile Sensor Array for RTSA. MICROMACHINES 2021; 12:1430. [PMID: 34832841 PMCID: PMC8620456 DOI: 10.3390/mi12111430] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022]
Abstract
This work presents a polymer-based tactile capacitive sensor capable of measuring joint reaction forces of reverse total shoulder arthroplasty (RTSA). The capacitive sensor contains a polydimethylsiloxane (PDMS) dielectric layer with an array of electrodes. The sensor was designed in such a way that four components of glenohumeral contact forces can be quantified to help ensure proper soft tissue tensioning during the procedure. Fabricated using soft lithography, the sensor has a loading time of approximately 400 ms when a 14.13 kPa load is applied and has a sensitivity of 1.24 × 10-3 pF/kPa at a load of 1649 kPa. A replica RTSA prothesis was 3D printed, and the sensor was mounted inside the humeral cap. Four static right shoulder positions were tested, and the results provided an intuitive graphical description of the pressure distribution across four quadrants of the glenohumeral joint contact surface. It may help clinicians choose a right implant size and offset that best fit a patient's anatomy and reduce postoperative biomechanical complications such as dislocation and stress fracture of the scapula.
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Affiliation(s)
- Elliott C. Leinauer
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO 65201, USA;
| | - H. Mike Kim
- Department of Orthopedic Surgery, University of Missouri, Columbia, MO 65201, USA;
| | - Jae W. Kwon
- Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO 65201, USA;
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19
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Palmowski Y, Popovic S, Schuster SG, Hardt S, Damm P. In vivo analysis of hip joint loading on Nordic walking novices. J Orthop Surg Res 2021; 16:596. [PMID: 34649562 PMCID: PMC8515744 DOI: 10.1186/s13018-021-02741-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 09/21/2021] [Indexed: 01/26/2023] Open
Abstract
Objective To evaluate the influence of Nordic walking (NW) on hip joint loads in order to determine whether it can be safely performed during postoperative physiotherapy in patients after orthopeadic surgery of the hip. Methods Internal hip joint loads were directly measured in vivo in 6 patients using instrumented hip prostheses during NW and ordinary walking (OW). All patients received training in two different NW techniques (double-poling and the diagonal technique) by a certified NW instructor. Measurements were conducted on a treadmill at a speed of 4 km/h on level ground, at 10% inclination and at 10% slope as well as on a level lawn at a self chosen comfortable speed. Resultant contact force (Fres), bending moment (Mbend) and torsional torque (Mtors) were compared between NW and OW as well as between both NW techniques. Results Joint loads showed a double peak pattern during all setups. Neither NW technique significantly influenced hip joint loads at the time of the first load peak during contralateral toe-off (CTO), which was also the absolute load peak, in comparison to OW. Compared to OW, double-poling significantly reduced Fres and Mbend at the time of the second load peak during the contralateral heel strike (CHS) on level ground both on the treadmill (− 6% and − 7%, respectively) and on the lawn (− 7% and − 9%). At 10% inclination, the diagonal technique increased Fres and Mbend at CHS (by + 6% and + 7%), but did not increase the absolute load peak at CTO. Conclusion Joint loads during NW are comparable to those of OW. Therefore, NW can be considered a low-impact activity and seems to be safe for patients that are allowed full weight bearing, e.g. during postoperative rehabilitation after THA.
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Affiliation(s)
- Yannick Palmowski
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117, Berlin, Germany
| | - Srdan Popovic
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Simone G Schuster
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Sebastian Hardt
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Chariteplatz 1, 10117, Berlin, Germany
| | - Philipp Damm
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Augustenburger Platz 1, 13353, Berlin, Germany.
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20
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Performance of a Piezoelectric Energy Harvesting System for an Energy-Autonomous Instrumented Total Hip Replacement: Experimental and Numerical Evaluation. MATERIALS 2021; 14:ma14185151. [PMID: 34576375 PMCID: PMC8470322 DOI: 10.3390/ma14185151] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/31/2021] [Accepted: 09/01/2021] [Indexed: 01/16/2023]
Abstract
Instrumented implants can improve the clinical outcome of total hip replacements (THRs). To overcome the drawbacks of external energy supply and batteries, energy harvesting is a promising approach to power energy-autonomous implants. Therefore, we recently presented a new piezoelectric-based energy harvesting concept for THRs. In this study, the performance of the proposed energy harvesting system was numerically and experimentally investigated. First, we numerically reproduced our previous results for the physiologically based loading situation in a simplified setup. Thereafter, this configuration was experimentally realised by the implantation of a functional model of the energy harvesting concept into an artificial bone segment. Additionally, the piezoelectric element alone was investigated to analyse the predictive power of the numerical model. We measured the generated voltage for a load profile for walking and calculated the power output. The maximum power for the directly loaded piezoelectric element and the functional model were 28.6 and 10.2 µW, respectively. Numerically, 72.7 µW was calculated. The curve progressions were qualitatively in good accordance with the numerical data. The deviations were explained by sensitivity analysis and model simplifications, e.g., material data or lower acting force levels by malalignment and differences between virtual and experimental implantation. The findings verify the feasibility of the proposed energy harvesting concept and form the basis for design optimisations with increased power output.
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21
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Damm P, Bender A, Waldheim V, Winkler T, Duda GN. Surgical cup placement affects the heating up of total joint hip replacements. Sci Rep 2021; 11:15851. [PMID: 34349160 PMCID: PMC8338953 DOI: 10.1038/s41598-021-95387-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 07/07/2021] [Indexed: 11/16/2022] Open
Abstract
The long-term success of highly effective total hip arthroplasty (THA) is mainly restricted by aseptic loosening, which is widely associated with friction between the head and cup liner. However, knowledge of the in vivo joint friction and resulting temperature increase is limited. Employing a novel combination of in vivo and in silico technologies, we analyzed the hypothesis that the intraoperatively defined implant orientation defines the individual joint roofing, friction and its associated temperature increase. A total of 38,000 in vivo activity trials from a special group of 10 subjects with instrumented THA implants with an identical material combination were analyzed and showed a significant link between implant orientation, joint kinematics, joint roofing and friction-induced temperature increase but surprisingly not with acting joint contact force magnitude. This combined in vivo and in silico analysis revealed that cup placement in relation to the stem is key to the in vivo joint friction and heating-up of THA. Thus, intraoperative placement, and not only articulating materials, should be the focus of further improvements, especially for young and more active patients.
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Affiliation(s)
- Philipp Damm
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany.
| | - Alwina Bender
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Vivian Waldheim
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Tobias Winkler
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
- Center for Musculoskeletal Surgery, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Georg N Duda
- Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
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22
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Haffer H, Popovic S, Martin F, Hardt S, Winkler T, Damm P. In vivo loading on the hip joint in patients with total hip replacement performing gymnastics and aerobics exercises. Sci Rep 2021; 11:13395. [PMID: 34183711 PMCID: PMC8239021 DOI: 10.1038/s41598-021-92788-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 06/09/2021] [Indexed: 01/17/2023] Open
Abstract
A further increase in the number of total hip arthroplasty (THA) is predicted, in particular the number of young THA patients has raised and with it their demands. There is no standardized evidence-based rehabilitation program and no reliable guidelines for sports activities after THA. Stretching and strengthening gymnastics are routinely performed in rehabilitation and aerobics as a sport after THA. The aim of the investigation was to determine the in vivo force and moments acting on the hip prosthesis during gymnastics and aerobic exercises to provide a source for evidence-based recommendations. Hip joint loads were measured in six patients with instrumented hip implants. The resulting force FRes, bending moment MBend at the neck and torsional moment MTors at the stem were examined during seven strengthening (with two different resistance bands) and four stretching gymnastic exercises and seven aerobic exercises with and without an aerobic step board compared to the loads during the reference activity walking. The stretching and strengthening gymnastics exercises and the aerobic exercises with and without a board demonstrated in their median peak force and moments mostly lower or similar values compared to walking. Significantly increased loads were recorded for the flexor stretching exercise in monopod stand (Fres and MBend), the strengthening abduction exercise on the chair (MTors) and the strengthening flexion exercise with the stronger resistance band (MTors). We also found a significant increase in median peak values in aerobic exercises with a board for the "Basic Step" (ipsilateral started Fres and MTors; contralateral started MTors), "Kickstep ipsilateral started" (Fres and MTors) and "Over the Top contralateral started" (Fres). The in vivo loads in THA patients during frequently performed stretching, strengthening and aerobic exercises were demonstrated for the first time. It was proved that stretching gymnastic exercises are safe in terms of resulting force, bending and torque moments for THA patients, although an external assistance for stabilization may be considered. Strengthening gymnastics exercises are reliable in terms of Fres, MBend and MTors, but, based on our data, we recommend to adhere to the communicated specific postoperative restrictions and select the resistance bands with lower tension. Aerobic exercises without an aerobic board can be considered as reliable activity in terms of force and moments for THA patients. Aerobic exercises with a board are not recommended for the early postoperative period and in our opinion need to be adapted to the individual muscular and coordinative resources.
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Affiliation(s)
- Henryk Haffer
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Srdan Popovic
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Franziska Martin
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany
| | - Sebastian Hardt
- Center for Musculoskeletal Surgery, Charité - Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universität Zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Tobias Winkler
- Berlin-Institute of Health, Center for Regenerative Therapies, Center for Musculoskeletal Surgery, Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Julius Wolff Institute, Berlin, Germany.
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Fischer MCM, Damm P, Habor J, Radermacher K. Effect of the underlying cadaver data and patient-specific adaptation of the femur and pelvis on the prediction of the hip joint force estimated using static models. J Biomech 2021; 139:110526. [PMID: 34092401 DOI: 10.1016/j.jbiomech.2021.110526] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 05/05/2021] [Accepted: 05/09/2021] [Indexed: 10/21/2022]
Abstract
The prediction of the hip joint force (HJF) is a fundamental factor for the prevention of edge loading in total hip arthroplasty. Naturally, the loading of the liner of the acetabular component depends on the HJF acting on the artificial joint. In contrast to dynamic musculoskeletal models, static models for HJF prediction do not require motion analysis of the patient. However, patient-specific adaptability and validity of static models have to be scrutinized. In this study, a modular framework for HJF prediction using static models is introduced to compare the results of different cadaver templates that are the basis of most static and dynamic models, and different scaling laws for the patient-specific adaptation with in vivo HJF of ten patients for one-leg stance and level walking. The results revealed the significant effect of the underlying cadaver template used for the prediction of the HJF (p < 0.01). A higher degree of patient-specific scaling of the cadaver template often did not significantly reduce the prediction error. Three static models with the lowest prediction errors were compared to results of dynamic models from literature. The prediction error of the peak HJF of the static models (median absolute errors below 15% body weight in magnitude and below 5° in direction) was similar in magnitude and even smaller in direction compared to dynamic models. The necessary reduction of a load-based target zone for the prevention of edge loading due to the uncertainty of the HJF prediction has to be considered in the preoperative planning. The framework for HJF prediction is openly accessible at https://github.com/RWTHmediTEC/HipJointForceModel.
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Affiliation(s)
- Maximilian C M Fischer
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Germany
| | - Philipp Damm
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Charité - Universitätsmedizin Berlin, Germany
| | - Juliana Habor
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Germany
| | - Klaus Radermacher
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Germany.
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24
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Analysis of hip joint loading during walking with different shoe types using instrumented total hip prostheses. Sci Rep 2021; 11:10073. [PMID: 33980984 PMCID: PMC8115277 DOI: 10.1038/s41598-021-89611-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 04/29/2021] [Indexed: 11/18/2022] Open
Abstract
Hip joint loads need careful consideration during postoperative physiotherapy after joint replacement. One factor influencing joint loads is the choice of footwear, but it remains unclear which footwear is favorable. The objective of the present study was to investigate the influence of footwear on hip joint loads in vivo. Instrumented hip endoprostheses were used for in vivo load measurements. The parameters resultant contact force (Fres), bending moment (Mbend) and torsional moment (Mtors) were evaluated during treadmill walking at 4 km/h with different shoe types. In general, footwear tended to increase hip joint loading, with the barefoot shoe having the least influence. Fres and Mbend were significantly increased during heel strike for all shoe types in comparison to barefoot walking, with everyday shoe (34.6%; p = 0.028 and 47%; p = 0.028, respectively) and men’s shoe (33.2%; p = 0.043 and 41.1%; p = 0.043, respectively) resulting in the highest changes. Mtors at AbsMax was increased by all shoes except for the barefoot shoe, with the highest changes for men’s shoe (+ 17.6%, p = 0.043) and the shoe with stiffened sole (+ 17.5%, p = 0.08). Shoes, especially those with stiff soles or elaborate cuishing and guiding elements, increase hip joint loads during walking. The influence on peak loads is higher for Mtors than for Fres and Mbend. For patients in which a reduction of hip joints loads is desired, e.g. during physiotherapy after recent surgery or to alleviate symptoms of osteoarthritis, low profile shoes with a flexible sole may be preferred over shoes with a stiff sole or elaborate cushioning elements.
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25
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Towards an effective sensing technology to monitor micro-scale interface loosening of bioelectronic implants. Sci Rep 2021; 11:3449. [PMID: 33568680 PMCID: PMC7876021 DOI: 10.1038/s41598-021-82589-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 01/13/2021] [Indexed: 12/25/2022] Open
Abstract
Instrumented implants are being developed with a radically innovative design to significantly reduce revision surgeries. Although bone replacements are among the most prevalent surgeries performed worldwide, implant failure rate usually surpasses 10%. High sophisticated multifunctional bioelectronic implants are being researched to incorporate cosurface capacitive architectures with ability to deliver personalized electric stimuli to peri-implant target tissues. However, the ability of these architectures to detect bone-implant interface states has never been explored. Moreover, although more than forty technologies were already proposed to detect implant loosening, none is able to ensure effective monitoring of the bone-implant debonding, mainly during the early stages of loosening. This work shows, for the first time, that cosurface capacitive sensors are a promising technology to provide an effective monitoring of bone-implant interfaces during the daily living of patients. Indeed, in vitro experimental tests and simulation with computational models highlight that both striped and circular capacitive architectures are able to detect micro-scale and macro-scale interface bonding, debonding or loosening, mainly when bonding is weakening or loosening is occurring. The proposed cosurface technologies hold potential to implement highly effective and personalized sensing systems such that the performance of multifunctional bioelectronic implants can be strongly improved. Findings were reported open a new research line on sensing technologies for bioelectronic implants, which may conduct to great impacts in the coming years.
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26
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Morosato F, Cristofolini L, Castagnini F, Traina F. Effect of cup medialization on primary stability of press-fit acetabular cups. Clin Biomech (Bristol, Avon) 2020; 80:105172. [PMID: 32927407 DOI: 10.1016/j.clinbiomech.2020.105172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Appropriate restoration of the native centre of rotation is of paramount importance in total hip arthroplasty. Reconstruction of the centre of rotation depends on reaming technique: conventional approaches require more cup medialization than anatomical preparations. To date, the influence of cup medialization on socket stability in cementless implants is still unknown. METHODS Ten cadaveric hemipelvises were sequentially reamed using anatomical technique (only subchondral bone removal with restoration of the native centre of rotation) and conventional preparation (reaming to the lamina and medializing the cup). A biomechanical test was performed on the reconstructions. Implant motions were measured with digital image correlation while a cyclic load of increasing magnitude was applied. FINDINGS No significant difference was measured between the two implantation techniques in terms of permanent cup migrations. The only significant difference was found for the cup inducible rotations, where the conventional technique was associated with larger rotations. INTERPRETATION Conventional reaming and cup medialization do not improve initial cup stability. Beyond the recently questioned concerns about medialization and hip biomechanics, this is another issue to bear in mind when reaming the acetabulum.
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Affiliation(s)
- Federico Morosato
- Department of Industrial Engineering, School of Engineering and Architecture, Alma Mater Studiorum - Università di Bologna, Bologna, Italy
| | - Luca Cristofolini
- Department of Industrial Engineering, School of Engineering and Architecture, Alma Mater Studiorum - Università di Bologna, Bologna, Italy.
| | | | - Francesco Traina
- Chirurgia Protesica, IRCCS Rizzoli Orthopaedic Institute, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, Università di Bologna, Italy
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27
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Anderson WD, Wilson SLM, Holdsworth DW. Development of a Wireless Telemetry Sensor Device to Measure Load and Deformation in Orthopaedic Applications. SENSORS 2020; 20:s20236772. [PMID: 33260821 PMCID: PMC7731148 DOI: 10.3390/s20236772] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 11/21/2020] [Accepted: 11/25/2020] [Indexed: 01/06/2023]
Abstract
Due to sensor size and supporting circuitry, in-vivo load and deformation measurements are currently restricted to applications within larger orthopaedic implants. The objective of this study is to repurpose a commercially available low-power, miniature, wireless, telemetric, tire-pressure sensor (FXTH87) to measure load and deformation for future use in orthopaedic and biomedical applications. The capacitive transducer membrane was modified, and compressive deformation was applied to the transducer to determine the sensor signal value and the internal resistive force. The sensor package was embedded within a deformable enclosure to illustrate potential applications of the sensor for monitoring load. To reach the maximum output signal value, sensors required compressive deformation of 350 ± 24 µm. The output signal value of the sensor was an effective predictor of the applied load on a calibrated plastic strain member, over a range of 35 N. The FXTH87 sensor can effectively sense and transmit load-induced deformations. The sensor does not have a limit on loads it can measure, as long as deformation resulting from the applied load does not exceed 350 µm. The proposed device presents a sensitive and precise means to monitor deformation and load within small-scale, deformable enclosures.
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Affiliation(s)
- William D. Anderson
- School of Biomedical Engineering, Western University, London, ON N6A 3K7, Canada; (W.D.A.); (S.L.M.W.)
| | - Sydney L. M. Wilson
- School of Biomedical Engineering, Western University, London, ON N6A 3K7, Canada; (W.D.A.); (S.L.M.W.)
| | - David W. Holdsworth
- School of Biomedical Engineering, Western University, London, ON N6A 3K7, Canada; (W.D.A.); (S.L.M.W.)
- Robarts Research Institute, Western University, London, ON N6A 5K8, Canada
- Department of Medical Biophysics, Western University, London, ON N6A 5C1, Canada
- Department of Surgery, Western University, London, ON N6A 4V2, Canada
- Correspondence:
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28
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Eidel B, Gote A, Fritzen CP, Ohrndorf A, Christ HJ. Tibial implant fixation in TKA worth a revision?-how to avoid stress-shielding even for stiff metallic implants. Comput Methods Biomech Biomed Engin 2020; 24:320-332. [PMID: 33063557 DOI: 10.1080/10255842.2020.1830274] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In total knee arthroplasty (TKA), force is transmitted into the tibia by a combined plate-stem device along with cemented or cementless stem fixation. The present work analyzes this force transmission in finite element simulations with the main aim to avoid reported postsurgical bone density reduction as a consequence of a reduced tibial bone loading. In the numerical analysis different implant materials, stem/extension lengths and implant-to-stem interface conditions are considered, from a stiff fully cemented fixation to sliding contact conditions with a low friction coefficient. The impact of these variations on bone loading changes are measured by (i) decomposing the total force into parts mediated by the plate and by the stem and by (ii) post-surgery strain energy density (SED) deviations. Based on a bionics-inspired perspective on how nature in pre-operative conditions carries out force transfer from the knee joint into the tibia, a modified implant-bone interface is suggested that alters force transmission towards physiological conditions while preserving the geometries of the standard plate-stem endoprosthesis design. The key aspect is that the axial force is predominantly transmitted through the plate into proximal bone which requires a compliant bone-stem interface as realized by sliding friction conditions at a low friction coefficient. These interface conditions avoid stress shielding almost completely, preserve pre-surgery bone loading such that bone resorption is not likely to occur.
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Affiliation(s)
- B Eidel
- DFG-Heisenberg-Group, Institut für Mechanik, University Siegen, Siegen, Germany
| | - A Gote
- DFG-Heisenberg-Group, Institut für Mechanik, University Siegen, Siegen, Germany
| | - C-P Fritzen
- Institut für Mechanik, Universität Siegen, Siegen, Germany
| | - A Ohrndorf
- Institut für Werkstofftechnik, Universität Siegen, Siegen, Germany
| | - H-J Christ
- Institut für Werkstofftechnik, Universität Siegen, Siegen, Germany
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29
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Morosato F, Traina F, Schierjott RA, Hettich G, Grupp TM, Cristofolini L. Primary Stability of Revision Acetabular Reconstructions Using an Innovative Bone Graft Substitute: A Comparative Biomechanical Study on Cadaveric Pelvises. MATERIALS 2020; 13:ma13194312. [PMID: 32992567 PMCID: PMC7579522 DOI: 10.3390/ma13194312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 11/16/2022]
Abstract
Hip implant failure is mainly due to aseptic loosening of the cotyle and is typically accompanied by defects in the acetabular region. Revision surgery aims to repair such defects before implantation by means of reconstruction materials, whose morselized bone graft represents the gold standard. Due to the limited availability of bone tissue, synthetic substitutes are also used. The aim of this study was to evaluate if a synthetic fully resorbable tri-calcium phosphate-based substitute can provide adequate mechanical stability when employed to restore severe, contained defects, in comparison with morselized bone graft. Five cadaveric pelvises were adopted, one side was reconstructed with morselized bone graft and the other with the synthetic substitute, consisting of dense calcium phosphate granules within a collagen matrix. During the biomechanical test, cyclic load packages of increasing magnitude were applied to each specimen until failure. Bone/implant motions were measured through Digital Image Correlation and were expressed in terms of permanent and inducible translations and rotations. The reconstruction types exhibited a similar behavior, consisting of an initial settling trend followed by failure as bone fracture (i.e., no failure of the reconstruction material). When 2.2 Body Weight was applied, the permanent translations were not significantly different between the two reconstructions (p = 0.06–1.0) and were below 1.0 mm. Similarly, the inducible translations did not differ significantly (p = 0.06–1.0) and were below 0.160 mm. Rotations presented the same order of magnitude but were qualitatively different. Overall, the synthetic substitute provided adequate mechanical stability in comparison with morselized bone graft, thus representing a reliable alternative to treat severe, contained acetabular defects.
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Affiliation(s)
- Federico Morosato
- Department of Industrial Engineering, Alma Mater Studiorum, Università di Bologna, 40131 Bologna, Italy;
| | - Francesco Traina
- Chirurgia Protesica, IRCCS Rizzoli Orthopaedic Institute, 40136 Bologna, Italy;
- Department of Biomedical and Neuromotor Sciences, Università di Bologna, 40126 Bologna, Italy
| | - Ronja A. Schierjott
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany; (R.A.S.); (G.H.); (T.M.G.)
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, Campus Grosshadern, Ludwig Maximilian University, 81377 Munich, Germany
| | - Georg Hettich
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany; (R.A.S.); (G.H.); (T.M.G.)
| | - Thomas M. Grupp
- Aesculap AG, Research & Development, Am Aesculap-Platz, 78532 Tuttlingen, Germany; (R.A.S.); (G.H.); (T.M.G.)
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, Campus Grosshadern, Ludwig Maximilian University, 81377 Munich, Germany
| | - Luca Cristofolini
- Department of Industrial Engineering, Alma Mater Studiorum, Università di Bologna, 40131 Bologna, Italy;
- Correspondence:
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30
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Nelson BD, Karipott SS, Wang Y, Ong KG. Wireless Technologies for Implantable Devices. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4604. [PMID: 32824365 PMCID: PMC7474418 DOI: 10.3390/s20164604] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/14/2020] [Accepted: 08/14/2020] [Indexed: 01/06/2023]
Abstract
Wireless technologies are incorporated in implantable devices since at least the 1950s. With remote data collection and control of implantable devices, these wireless technologies help researchers and clinicians to better understand diseases and to improve medical treatments. Today, wireless technologies are still more commonly used for research, with limited applications in a number of clinical implantable devices. Recent development and standardization of wireless technologies present a good opportunity for their wider use in other types of implantable devices, which will significantly improve the outcomes of many diseases or injuries. This review briefly describes some common wireless technologies and modern advancements, as well as their strengths and suitability for use in implantable medical devices. The applications of these wireless technologies in treatments of orthopedic and cardiovascular injuries and disorders are described. This review then concludes with a discussion on the technical challenges and potential solutions of implementing wireless technologies in implantable devices.
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Affiliation(s)
- Bradley D. Nelson
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA; (B.D.N.); (S.S.K.)
| | - Salil Sidharthan Karipott
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA; (B.D.N.); (S.S.K.)
| | - Yvonne Wang
- Department of Biomedical Engineering, Michigan Technological University, Houghton, MI 49931, USA;
| | - Keat Ghee Ong
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR 97403, USA; (B.D.N.); (S.S.K.)
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31
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Damm P, Reitmaier S, Hahn S, Waldheim V, Firouzabadi A, Schmidt H. In vivo hip and lumbar spine implant loads during activities in forward bent postures. J Biomech 2020; 102:109517. [PMID: 31767284 DOI: 10.1016/j.jbiomech.2019.109517] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/22/2019] [Accepted: 11/11/2019] [Indexed: 11/25/2022]
Abstract
Long-term measurements on the lumbar spinal alignment during daily life revealed that humans spent 90% of the day in a forward bent posture. Compared to standing, this posture leads to a substantial increase in spinal loading. The lumbar spine and pelvis, however, contribute differently to the total amount of flexion, which could possibly indicate a different timing of maximum loads in both structures during flexion. This study aimed to evaluate the in vivo implant forces in the hip and lumbar spine during activities in forward bent postures. This work utilized data collected in earlier in vivo measurements on patients either with telemeterized hip endoprostheses (HE) or vertebral body replacements (VBR). The following activities were investigated: standing, upper body flexion with and without weights in the hands using different lifting techniques (straight and bent knees). The maximum resultant forces in VBR were considerably lower than in HE. Increases in flexion inclinations caused direct increases of the resultant forces within VBR, followed by a plateau or even a decrease of the force until maximum inclination. The resultant force in HE displayed an almost continuous increase until the maximum inclination. This general curve behavior resulted in different HE-VBR load ratios, which were affected by lifting additional weights or different lifting techniques. The results emphasize that maximum loads in the spine, in contrast to the hip, do not necessarily occur at maximum upper body flexion as normally expected, rather already at intermediate flexion angles in VBR patients. The results form the basis for more detailed insilico analyzes.
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Affiliation(s)
- Philipp Damm
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany
| | - Sandra Reitmaier
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany
| | - Sabine Hahn
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany
| | - Vivian Waldheim
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany
| | - Ali Firouzabadi
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany
| | - Hendrik Schmidt
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Germany.
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32
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Weinhandl JT, Bennett HJ. Musculoskeletal model choice influences hip joint load estimations during gait. J Biomech 2019; 91:124-132. [DOI: 10.1016/j.jbiomech.2019.05.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 05/13/2019] [Accepted: 05/13/2019] [Indexed: 10/26/2022]
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33
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Bergmann G, Kutzner I, Bender A, Dymke J, Trepczynski A, Duda GN, Felsenberg D, Damm P. Loading of the hip and knee joints during whole body vibration training. PLoS One 2018; 13:e0207014. [PMID: 30540775 PMCID: PMC6291191 DOI: 10.1371/journal.pone.0207014] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 10/23/2018] [Indexed: 11/18/2022] Open
Abstract
During whole body vibrations, the total contact force in knee and hip joints consists of a static component plus the vibration-induced dynamic component. In two different cohorts, these forces were measured with instrumented joint implants at different vibration frequencies and amplitudes. For three standing positions on two platforms, the dynamic forces were compared to the static forces, and the total forces were related to the peak forces during walking. A biomechanical model served for estimating muscle force increases from contact force increases. The median static forces were 122% to 168% (knee), resp. 93% to 141% (hip), of the body weight. The same accelerations produced higher dynamic forces for alternating than for parallel foot movements. The dynamic forces individually differed much between 5.3% to 27.5% of the static forces in the same positions. On the Powerplate, they were even close to zero in some subjects. The total forces were always below 79% of the forces during walking. The dynamic forces did not rise proportionally to platform accelerations. During stance (Galileo, 25 Hz, 2 mm), the damping of dynamic forces was only 8% between foot and knee but 54% between knee and hip. The estimated rises in muscle forces due to the vibrations were in the same ranges as the contact force increases. These rises were much smaller than the vibration-induced EMG increases, reported for the same platform accelerations. These small muscle force increases, along with the observation that the peak contact and muscle forces during vibrations remained far below those during walking, indicate that dynamic muscle force amplitudes cannot be the reason for positive effects of whole body vibrations on muscles, bone remodelling or arthritic joints. Positive effects of vibrations must be caused by factors other than raised forces amplitudes.
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Affiliation(s)
- Georg Bergmann
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Ines Kutzner
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Alwina Bender
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Jörn Dymke
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Adam Trepczynski
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Georg N. Duda
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Dieter Felsenberg
- Center for Muscle and Bone Research, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Berlin, Germany
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34
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Bergmann G, Bender A, Dymke J, Duda GN, Damm P. Physical Activities That Cause High Friction Moments at the Cup in Hip Implants. J Bone Joint Surg Am 2018; 100:1637-1644. [PMID: 30277993 DOI: 10.2106/jbjs.17.01298] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND High friction moments in hip implants contribute to the aseptic loosening of cementless cups, of which there are approximately 100,000 cases per year; sustained joint loading may cause such high moments. The most "critical" physical activities associated with sustained joint loading were identified in this study. METHODS Friction moments in the cup were telemetrically measured about 33,000 times in the endoprostheses of 9 subjects during >1,400 different activities. The highest moments were compared with the cup's fixation stability limit of approximately 4 Nm. RESULTS A total of 124 different activities caused friction moments meeting or exceeding the critical limit, with the highest value of 11.5 Nm. Most involved sustained high contact forces before or during the activity. The highest peak moments (6.3 to 11.5 Nm) occurred when moving the contralateral leg during 1-legged stance, during breaststroke swimming, muscle stretching, 2-legged stance with muscle contraction, and during static 1-legged stance. The median moments were highest (3.4 to 3.9 Nm) for unstable 1-legged stance, whole-body vibration training, 2-legged stance with an unexpected push at the upper body, 1-legged stance while exercising the contralateral leg, and running after 2-legged stance. CONCLUSIONS Frequent unloading plus simultaneous movement of the joint are required to maintain good joint lubrication and keep the friction moments low. Frequent, sustained high loads before or during an activity may cause or contribute to aseptic cup loosening. During the first months after hip arthroplasty, such activities should be avoided or reduced as much as possible. This especially applies during postoperative physiotherapy. Whether these guidelines also apply for subjects with knee implants or arthrotic hip or knee joints requires additional investigation. CLINICAL RELEVANCE The risk of aseptic cup loosening may be reduced by avoiding sustained loading of hip implants without periodic joint movement.
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Affiliation(s)
- Georg Bergmann
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Alwina Bender
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jörn Dymke
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Georg N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
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35
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Ledet EH, Liddle B, Kradinova K, Harper S. Smart implants in orthopedic surgery, improving patient outcomes: a review. ACTA ACUST UNITED AC 2018; 5:41-51. [PMID: 30246037 PMCID: PMC6145822 DOI: 10.2147/ieh.s133518] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Smart implants are implantable devices that provide not only therapeutic benefits but also have diagnostic capabilities. The integration of smart implants into daily clinical practice has the potential for massive cost savings to the health care system. Applications for smart orthopedic implants have been identified for knee arthroplasty, hip arthroplasty, spine fusion, fracture fixation and others. To date, smart orthopedic implants have been used to measure physical parameters from inside the body, including pressure, force, strain, displacement, proximity and temperature. The measurement of physical stimuli is achieved through integration of application-specific technology with the implant. Data from smart implants have led to refinements in implant design, surgical technique and strategies for postoperative care and rehabilitation. In spite of decades of research, with very few exceptions, smart implants have not yet become a part of daily clinical practice. This is largely because integration of current sensor technology necessitates significant modification to the implants. While the technology underlying smart implants has matured significantly over the last several decades, there are still significant technical challenges that need to be overcome before smart implants become part of mainstream health care. Sensors for next-generation smart implants will be small, simple, robust and inexpensive and will necessitate little to no modification to existing implant designs. With rapidly advancing technology, the widespread implementation of smart implants is near. New sensor technology that minimizes modifications to existing implants is the key to enabling smart implants into daily clinical practice.
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Affiliation(s)
- Eric H Ledet
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA.,R&D Service, Stratton VA Medical Center, Albany, NY, USA
| | - Benjamin Liddle
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Katerina Kradinova
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Sara Harper
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute, Troy, NY, USA
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36
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Eidel B, Gote A, Ohrndorf A, Christ HJ. How can a short stem hip implant preserve the natural, pre-surgery force flow? A finite element analysis on a collar cortex compression concept (CO 4). Med Eng Phys 2018; 58:S1350-4533(18)30076-6. [PMID: 29773487 DOI: 10.1016/j.medengphy.2018.04.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 03/17/2018] [Accepted: 04/16/2018] [Indexed: 10/28/2022]
Abstract
The present work proposes a simple, novel fixation concept for short stem hip endoprostheses, which preserves the pre-surgery force flow through femoral bone to an unprecedented extent. It is demonstrated by finite element analyses that a standard implant model endowed with minor geometrical changes can overcome bone loading reduction and can achieve almost physiological conditions. The numerical results underpin that the key aspect of the novel, so-called "collar cortex compression concept CO4" is the direct, almost full load transmission from the implant collar to the resected femur cortex, which implies that the implant stem must be smooth and therefore interacts mainly by normal contact with the surrounding bone. For a stem endowed with surface porosity at already small areas, it is mainly the stem which transmits axial forces by shear, whereas the collar shows considerable unloading, which is the standard metaphyseal fixation. Only in the latter case the implant-bone stiffness contrast induces stress shielding, whereas for CO4 stress shielding is avoided almost completely, although the implant is made of a stiff Ti-alloy. CO4 is bionics-inspired in that it mimics force transmission at implant-bone interfaces following the natural conditions and it thereby preserves pre-surgery bone architecture as an optimized solution of nature.
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Affiliation(s)
- B Eidel
- Heisenberg-Group, Universität Siegen 57068 Siegen, Paul-Bonatz-Str. 9-11, Germany.
| | - A Gote
- Heisenberg-Group, Universität Siegen 57068 Siegen, Paul-Bonatz-Str. 9-11, Germany
| | - A Ohrndorf
- Institut für Werkstofftechnik, Universität Siegen, 57068 Siegen, Paul-Bonatz-Str. 9-11, Germany
| | - H-J Christ
- Institut für Werkstofftechnik, Universität Siegen, 57068 Siegen, Paul-Bonatz-Str. 9-11, Germany
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37
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Fischer MCM, Eschweiler J, Schick F, Asseln M, Damm P, Radermacher K. Patient-specific musculoskeletal modeling of the hip joint for preoperative planning of total hip arthroplasty: A validation study based on in vivo measurements. PLoS One 2018; 13:e0195376. [PMID: 29649235 PMCID: PMC5896969 DOI: 10.1371/journal.pone.0195376] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 03/21/2018] [Indexed: 11/30/2022] Open
Abstract
Validation of musculoskeletal models for application in preoperative planning is still a challenging task. Ideally, the simulation results of a patient-specific musculoskeletal model are compared to corresponding in vivo measurements. Currently, the only possibility to measure in vivo joint forces is to implant an instrumented prosthesis in patients undergoing a total joint replacement. In this study, a musculoskeletal model of the AnyBody Modeling System was adapted patient-specifically and validated against the in vivo hip joint force measurements of ten subjects performing one-leg stance and level walking. The impact of four model parameters was evaluated; hip joint width, muscle strength, muscle recruitment, and type of muscle model. The smallest difference between simulated and in vivo hip joint force was achieved by using the hip joint width measured in computed tomography images, a muscle strength of 90 N/cm2, a third order polynomial muscle recruitment, and a simple muscle model. This parameter combination reached mean deviations between simulation and in vivo measurement during the peak force phase of 12% ± 14% in magnitude and 11° ± 5° in orientation for one-leg stance and 8% ± 6% in magnitude and 10° ± 5° in orientation for level walking.
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Affiliation(s)
- Maximilian C. M. Fischer
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
- * E-mail:
| | - Jörg Eschweiler
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
- Department for Orthopaedic Surgery, University Hospital RWTH Aachen, Germany
| | - Fabian Schick
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
| | - Malte Asseln
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
| | - Philipp Damm
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Charité - Universitätsmedizin Berlin, Germany
| | - Klaus Radermacher
- Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany
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38
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Karipott SS, Nelson BD, Guldberg RE, Ong KG. Clinical potential of implantable wireless sensors for orthopedic treatments. Expert Rev Med Devices 2018; 15:255-264. [PMID: 29558820 DOI: 10.1080/17434440.2018.1454310] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Implantable wireless sensors have been used for real-time monitoring of chemicals and physical conditions of bones, tendons and muscles to diagnose and study orthopedic diseases and injuries. Due to the importance of these sensors in orthopedic care, a critical review, which not only analyzes the underlying technologies but also their clinical implementations and challenges, will provide a landscape view on their current state and their future clinical role. AREAS COVERED By conducting an extensive literature search and following the leaders of orthopedic implantable wireless sensors, this review covers the battery-powered and battery-free wireless implantable sensor technologies, and describes their implementation for hips, knees, spine, and shoulder stress/strain monitoring. Their advantages, limitations, and clinical challenges are also described. EXPERT COMMENTARY Currently, implantable wireless sensors are mostly limited for scientific investigations and demonstrative experiments. Although rapid advancement in sensors and wireless technologies will push the reliability and practicality of these sensors for clinical realization, regulatory constraints and financial viability in medical device industry may curtail their continuous adoption for clinical orthopedic applications. In the next five years, these sensors are expected to gain increased interest from researchers, but wide clinical adoption is still unlikely.
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Affiliation(s)
| | - Bradley D Nelson
- a Biomedical Engineering , Michigan Technological University , Houghton , MI , USA
| | - Robert E Guldberg
- b George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , GA , USA
| | - Keat Ghee Ong
- a Biomedical Engineering , Michigan Technological University , Houghton , MI , USA
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39
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Effect of arm swinging on lumbar spine and hip joint forces. J Biomech 2018; 70:185-195. [DOI: 10.1016/j.jbiomech.2017.09.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/20/2017] [Accepted: 09/06/2017] [Indexed: 11/20/2022]
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40
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Cilla M, Checa S, Duda GN. Strain shielding inspired re-design of proximal femoral stems for total hip arthroplasty. J Orthop Res 2017; 35:2534-2544. [PMID: 28176355 DOI: 10.1002/jor.23540] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 01/27/2017] [Indexed: 02/04/2023]
Abstract
A large number of hip prosthesis with different designs have been developed. However, the influence of hip implant design changes on the strains induced in the bone remains unclear. The purpose of this study is to better understand the mechanics of short stem total hip arthroplasty. Specifically, it investigates whether strain shielding can be avoided by changing implant shape and/or material properties. It is hypothesized that the re-design of existing implant designs can result in further reduction of strain shielding and thus keep bone loss minimal following total hip replacement. Finite element methods were used to compare healthy and implanted models. The local mechanics strains/stresses in the intact and implanted femurs were determined under patient-specific muscle and joint contact forces. Results suggest that small changes in implant geometry and material properties have no major effect on strain shielding. Furthermore, it was found that improvement depends on a dramatic re-design of the original implant design. Whereas the benefit of this strategy of modification of the original geometry of a given short-stemmed hip consists in reduced bone remodeling, care should be taken with regard to long-term bone anchorage and implant fatigue strength. It is also shown that geometrical and material changes have a limited potential in avoiding strain shielding even in short-stemmed implants. Finally, it is suggested that an understanding of the influence of these changes on the strain distribution within the bone can guide in the process of optimizing the current stem designs toward minimal strain shielding effects. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2534-2544, 2017.
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Affiliation(s)
- Myriam Cilla
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Campus - Virchow Klinikum, Augustenburger Platz 1, Institutsgebäude Süd,13353 Berlin, Germany.,Centro Universitario de la Defensa, Academia General Militar, Ctra. Huesca s/n, 50090 Zaragoza, Spain.,Aragón Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain
| | - Sara Checa
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Campus - Virchow Klinikum, Augustenburger Platz 1, Institutsgebäude Süd,13353 Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Georg N Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Campus - Virchow Klinikum, Augustenburger Platz 1, Institutsgebäude Süd,13353 Berlin, Germany.,Berlin-Brandenburg School for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Berlin, Germany
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41
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Leuridan S, Goossens Q, Vander Sloten T, De Landsheer K, Delport H, Pastrav L, Denis K, Desmet W, Vander Sloten J. Vibration-based fixation assessment of tibial knee implants: A combined in vitro and in silico feasibility study. Med Eng Phys 2017; 49:109-120. [DOI: 10.1016/j.medengphy.2017.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 07/07/2017] [Accepted: 08/13/2017] [Indexed: 10/18/2022]
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42
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Cilla M, Borgiani E, Martínez J, Duda GN, Checa S. Machine learning techniques for the optimization of joint replacements: Application to a short-stem hip implant. PLoS One 2017; 12:e0183755. [PMID: 28873093 PMCID: PMC5584793 DOI: 10.1371/journal.pone.0183755] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/10/2017] [Indexed: 12/28/2022] Open
Abstract
Today, different implant designs exist in the market; however, there is not a clear understanding of which are the best implant design parameters to achieve mechanical optimal conditions. Therefore, the aim of this project was to investigate if the geometry of a commercial short stem hip prosthesis can be further optimized to reduce stress shielding effects and achieve better short-stemmed implant performance. To reach this aim, the potential of machine learning techniques combined with parametric Finite Element analysis was used. The selected implant geometrical parameters were: total stem length (L), thickness in the lateral (R1) and medial (R2) and the distance between the implant neck and the central stem surface (D). The results show that the total stem length was not the only parameter playing a role in stress shielding. An optimized implant should aim for a decreased stem length and a reduced length of the surface in contact with the bone. The two radiuses that characterize the stem width at the distal cross-section in contact with the bone were less influential in the reduction of stress shielding compared with the other two parameters; but they also play a role where thinner stems present better results.
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Affiliation(s)
- Myriam Cilla
- Centro Universitario de la Defensa (CUD), Academia General Militar, Zaragoza, Spain
- Aragón Institute of Engineering Research (I3A), University of Zaragoza, Zaragoza, Spain
| | - Edoardo Borgiani
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Javier Martínez
- Centro Universitario de la Defensa (CUD), Escuela Naval Militar, Marín, Spain
| | - Georg N. Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Sara Checa
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Berlin, Germany
- Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin-Brandenburg School for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany
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43
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Damm P, Dymke J, Bender A, Duda G, Bergmann G. In vivo hip joint loads and pedal forces during ergometer cycling. J Biomech 2017; 60:197-202. [PMID: 28709659 DOI: 10.1016/j.jbiomech.2017.06.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/02/2017] [Accepted: 06/25/2017] [Indexed: 11/18/2022]
Abstract
The rising prevalence of osteoarthritis and an increase in total hip replacements calls for attention to potential therapeutic activities. Cycling is considered as a low impact exercise for the hip joint and hence recommended. However, there are limited data about hip joint loading to support this claim. The aim of this study was to measure synchronously the in vivo hip joint loads and pedal forces during cycling. The in vivo hip joint loads were measured in 5 patients with instrumented hip implants. Data were collected at several combinations of power and cadence, at two saddle heights. Joint loads and pedal forces showed strong linear correlation with power. So the relationship between the external pedal forces and internal joint forces was shown. While cycling at different cadences the minimum joint loads were acquired at 60RPM. The lower saddle height configuration results in an approximately 15% increase compared to normal saddle height. The results offered new insights into the actual effects of cycling on the hip joint and can serve as useful tools while developing an optimum cycling regimen for individuals with coxarthrosis or following total hip arthroplasty. Due to the relatively low contact forces, cycling at a moderate power level of 90W at a normal saddle height is suitable for patients.
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Affiliation(s)
- P Damm
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
| | - J Dymke
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - A Bender
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - G Duda
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - G Bergmann
- Julius Wolff Institute, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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44
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Su S, Zhou Y, Wang Z, Chen H. Monocular Vision- and IMU-Based System for Prosthesis Pose Estimation During Total Hip Replacement Surgery. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2017; 11:661-670. [PMID: 28371783 DOI: 10.1109/tbcas.2016.2643626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The average age of population increases worldwide, so does the number of total hip replacement surgeries. Total hip replacement, however, often involves a risk of dislocation and prosthetic impingement. To minimize the risk after surgery, we propose an instrumented hip prosthesis that estimates the relative pose between prostheses intraoperatively and ensures the placement of prostheses within a safe zone. We create a model of the hip prosthesis as a ball and socket joint, which has four degrees of freedom (DOFs), including 3-DOF rotation and 1-DOF translation. We mount a camera and an inertial measurement unit (IMU) inside the hollow ball, or "femoral head prosthesis," while printing customized patterns on the internal surface of the socket, or "acetabular cup." Since the sensors were rigidly fixed to the femoral head prosthesis, measuring its motions poses a sensor ego-motion estimation problem. By matching feature points in images of the reference patterns, we propose a monocular vision based method with a relative error of less than 7% in the 3-DOF rotation and 8% in the 1-DOF translation. Further, to reduce system power consumption, we apply the IMU with its data fused by an extended Kalman filter to replace the camera in the 3-DOF rotation estimation, which yields a less than 4.8% relative error and a 21.6% decrease in power consumption. Experimental results show that the best approach to prosthesis pose estimation is a combination of monocular vision-based translation estimation and IMU-based rotation estimation, and we have verified the feasibility and validity of this system in prosthesis pose estimation.
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45
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Roth JD, Howell SM, Hull ML. Characterization and Correction of Errors in Computing Contact Location Between Curved Articular Surfaces: Application to Total Knee Arthroplasty. J Biomech Eng 2017; 139:2610239. [PMID: 28267191 DOI: 10.1115/1.4036147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Indexed: 11/08/2022]
Abstract
In total knee arthroplasty (TKA), one common metric used to evaluate innovations in component designs, methods of component alignment, and surgical techniques aimed at decreasing the high rate of patient-reported dissatisfaction is tibiofemoral contact kinematics. Tibiofemoral contact kinematics are determined based on the movement of the contact locations in the medial and lateral compartments of the tibia during knee flexion. A tibial force sensor is a useful instrument to determine the contact locations, because it can simultaneously determine contact forces and contact locations. Previous reports of tibial force sensors have neither characterized nor corrected errors in the computed contact location (i.e., center of pressure) between the femoral and tibial components in TKA that, based on a static analysis, are caused by the curved articular surface of the tibial component. The objectives were to experimentally characterize these errors and to develop and validate an error correction algorithm. The errors were characterized by calculating the difference between the errors in the computed contact locations when forces were applied normal to the tibial articular surface and those when forces were applied normal to the tibial baseplate. The algorithm generated error correction functions to minimize these errors and was validated by determining how much the error correction functions reduced the errors in the computed contact location caused by the curved articular surface. The curved articular surface primarily caused bias (i.e., average or systematic error) which ranged from 1.0 to 2.7 mm in regions of high curvature. The error correction functions reduced the bias in these regions to negligible levels ranging from 0.0 to 0.6 mm (p < 0.001). Bias in the computed contact locations caused by the curved articular surface of the tibial component as small as 1 mm needs to be accounted for, because it might inflate the computed internal-external rotation and anterior-posterior translation of femur on the tibia leading to false identifications of clinically undesirable contact kinematics (e.g., internal rotation and anterior translation during flexion). Our novel error correction algorithm is an effective method to account for this bias to more accurately compute contact kinematics.
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Affiliation(s)
- Joshua D Roth
- Biomedical Engineering Graduate Group, UC Davis, 4635 2nd Avenue (Building 97), Sacramento, CA 95817 e-mail:
| | - Stephen M Howell
- Department of Biomedical Engineering, UC Davis, 451 E. Health Sciences Drive, Davis, CA 95616 e-mail:
| | - Maury L Hull
- Department of Orthopaedic Surgery, UC Davis, 4635 2nd Avenue (Building 97), Sacramento, CA 95817;Department of Biomedical Engineering, UC Davis, 451 E. Health Sciences Drive, Davis, CA 95616;Department of Mechanical Engineering, UC Davis, One Shields Avenue, Davis, CA 95616 e-mail:
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46
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Damm P, Bender A, Duda G, Bergmann G. In vivo measured joint friction in hip implants during walking after a short rest. PLoS One 2017; 12:e0174788. [PMID: 28350858 PMCID: PMC5370152 DOI: 10.1371/journal.pone.0174788] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 03/15/2017] [Indexed: 11/18/2022] Open
Abstract
Introduction It has been suspected that friction in hip implants is higher when walking is initiated after a resting period than during continuous movement. It cannot be excluded that such increased initial moments endanger the cup fixation in the acetabulum, overstress the taper connections in the implant or increase wear. To assess these risks, the contact forces, friction moments and friction coefficients in the joint were measured in vivo in ten subjects. Instrumented hip joint implants with telemetric data transmission were used to access the contact loads between the cup and head during the first steps of walking after a short rest. Results The analysis demonstrated that the contact force is not increased during the first step. The friction moment in the joint, however, is much higher during the first step than during continuous walking. The moment increases throughout the gait cycle were 32% to 143% on average and up to 621% individually. The high initial moments will probably not increase wear by much in the joint. However, comparisons with literature data on the fixation resistance of the cup against moments made clear that the stability can be endangered. This risk is highest during the first postoperative months for cementless cups with insufficient under-reaming. The high moments after a break can also put taper connections between the head and neck and neck and shaft at a higher risk. Discussion During continuous walking, the friction moments individually were extremely varied by factors of 4 to 10. Much of this difference is presumably caused by the varying lubrication properties of the synovia. These large moment variations can possibly lead to friction-induced temperature increases during walking, which are higher than the 43.1°C which have previously been observed in a group of only five subjects.
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Affiliation(s)
- Philipp Damm
- Julius Wolff Institute, Charité–Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
| | - Alwina Bender
- Julius Wolff Institute, Charité–Universitätsmedizin Berlin, Berlin, Germany
| | - Georg Duda
- Julius Wolff Institute, Charité–Universitätsmedizin Berlin, Berlin, Germany
| | - Georg Bergmann
- Julius Wolff Institute, Charité–Universitätsmedizin Berlin, Berlin, Germany
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47
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Does aquatic exercise reduce hip and knee joint loading? In vivo load measurements with instrumented implants. PLoS One 2017; 12:e0171972. [PMID: 28319145 PMCID: PMC5358747 DOI: 10.1371/journal.pone.0171972] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 01/28/2017] [Indexed: 11/19/2022] Open
Abstract
Aquatic exercises are widely used for rehabilitation or preventive therapies in order to enable mobilization and muscle strengthening while minimizing joint loading of the lower limb. The load reducing effect of water due to buoyancy is a main advantage compared to exercises on land. However, also drag forces have to be considered that act opposite to the relative motion of the body segments and require higher muscle activity. Due to these opposing effects on joint loading, the load-reducing effect during aquatic exercises remains unknown. The aim of this study was to quantify the joint loads during various aquatic exercises and to determine the load reducing effect of water. Instrumented knee and hip implants with telemetric data transfer were used to measure the resultant joint contact forces in 12 elderly subjects (6x hip, 6x knee) in vivo. Different dynamic, weight-bearing and non-weight-bearing activities were performed by the subjects on land and in chest-high water. Non-weight-bearing hip and knee flexion/extension was performed at different velocities and with additional Aquafins. Joint forces during aquatic exercises ranged between 32 and 396% body weight (BW). Highest forces occurred during dynamic activities, followed by weight-bearing and slow non-weight-bearing activities. Compared to the same activities on land, joint forces were reduced by 36–55% in water with absolute reductions being greater than 100%BW during weight-bearing and dynamic activities. During non-weight-bearing activities, high movement velocities and additional Aquafins increased the joint forces by up to 59% and resulted in joint forces of up to 301%BW. This study confirms the load reducing effect of water during weight-bearing and dynamic exercises. Nevertheless, high drag forces result in increased joint contact forces and indicate greater muscle activity. By the choice of activity, movement velocity and additional resistive devices joint forces can be modulated individually in the course of rehabilitation or preventive therapies.
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48
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Damm P, Kutzner I, Bergmann G, Rohlmann A, Schmidt H. Comparison of in vivo measured loads in knee, hip and spinal implants during level walking. J Biomech 2016; 51:128-132. [PMID: 27914627 DOI: 10.1016/j.jbiomech.2016.11.060] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 11/21/2016] [Accepted: 11/22/2016] [Indexed: 10/20/2022]
Abstract
Walking is a task that we seek to understand because it is the most relevant human locomotion. Walking causes complex loading patterns and high load magnitudes within the human body. This work summarizes partially published load data collected in earlier in vivo measurement studies on 9 patients with telemeterized knee endoprostheses, 10 with hip endoprostheses and 5 with vertebral body replacements. Moreover, for the 19 endoprosthesis patients, additional simultaneously measured and previously unreported ground reaction forces are presented. The ground reaction force and the implant forces in the knee and hip exhibited a double peak during each step. The maxima of the ground reaction forces ranged from 100% to 126% bodyweight. In comparison, the greatest implant forces in the hip (249% bodyweight) and knee (271% bodyweight) were much greater. The mean peak force measured in the vertebral body replacement was 39% bodyweight and occurred at different time points of the stance phase. We concluded that walking leads to high load magnitudes in the knee and hip, whereas the forces in the vertebral body replacement remained relatively low. This indicates that the first peak force was greater in the hip than in the knee joint while this was reversed for the second peak force. The forces in the spinal implant were considerably lower than in the knee and hip joints.
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Affiliation(s)
- Philipp Damm
- Julius Wolff Institut Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany.
| | - Ines Kutzner
- Julius Wolff Institut Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Georg Bergmann
- Julius Wolff Institut Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Antonius Rohlmann
- Julius Wolff Institut Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Hendrik Schmidt
- Julius Wolff Institut Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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New cosurface capacitive stimulators for the development of active osseointegrative implantable devices. Sci Rep 2016; 6:30231. [PMID: 27456818 PMCID: PMC4960616 DOI: 10.1038/srep30231] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/28/2016] [Indexed: 12/12/2022] Open
Abstract
Non-drug strategies based on biophysical stimulation have been emphasized for the treatment and prevention of musculoskeletal conditions. However, to date, an effective stimulation system for intracorporeal therapies has not been proposed. This is particularly true for active intramedullary implants that aim to optimize osseointegration. The increasing demand for these implants, particularly for hip and knee replacements, has driven the design of innovative stimulation systems that are effective in bone-implant integration. In this paper, a new cosurface-based capacitive system concept is proposed for the design of implantable devices that deliver controllable and personalized electric field stimuli to target tissues. A prototype architecture of this system was constructed for in vitro tests, and its ability to deliver controllable stimuli was numerically analyzed. Successful results were obtained for osteoblastic proliferation and differentiation in the in vitro tests. This work provides, for the first time, a design of a stimulation system that can be embedded in active implantable devices for controllable bone-implant integration and regeneration. The proposed cosurface design holds potential for the implementation of novel and innovative personalized stimulatory therapies based on the delivery of electric fields to bone cells.
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Bergmann G, Bender A, Dymke J, Duda G, Damm P. Standardized Loads Acting in Hip Implants. PLoS One 2016; 11:e0155612. [PMID: 27195789 PMCID: PMC4873223 DOI: 10.1371/journal.pone.0155612] [Citation(s) in RCA: 172] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 05/02/2016] [Indexed: 11/30/2022] Open
Abstract
With the increasing success of hip joint replacements, the average age of patients has decreased, patients have become more active and their expectations of the implant durability have risen. Thus, pre-clinical endurance tests on hip implants require defining realistic in vivo loads from younger and more active patients. These loads require simplifications to be applicable for simulator tests and numerical analyses. Here, the contact forces in the joint were measured with instrumented hip implants in ten subjects during nine of the most physically demanding and frequent activities of daily living. Typical levels and directions of average and high joint loads were extracted from the intra- and inter-individually widely varying individual data. These data can also be used to analyse bone remodelling at the implant-bone interface, evaluate tissue straining in finite element studies or validate analytical loading predictions, among other uses. The current ISO standards for endurance tests of implant stems and necks are based on historic analytical data from the 1970s. Comparisons of these test forces with in vivo loads unveiled that their unidirectional orientations deviate from the time-dependent in vivo directions during walking and most other activities. The ISO force for testing the stem is substantially too low while the ISO force for the neck better matches typical in vivo magnitudes. Because the magnitudes and orientations of peak forces substantially vary among the activities, load scenarios that reflect a collection of time-dependent high forces should be applied rather than using unidirectional forces. Based on data from ten patients, proposals for the most demanding activities, the time courses of the contact forces and the required cycle numbers for testing are given here. Friction moments in the joint were measured in addition to the contact forces. The moment data were also standardized and can be applied to wear tests of the implant. It was shown that friction only very slightly influences the stresses in the implant neck and shaft.
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Affiliation(s)
- Georg Bergmann
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Alwina Bender
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Jörn Dymke
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Georg Duda
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Philipp Damm
- Julius Wolff Institute, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
- * E-mail:
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