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Walker J, Erbulut D, Rebgetz PR, Taylor FJ. Added transverse screw in tripod construct increases stiffness in Mason III radial head fractures: a finite element analysis. J Shoulder Elbow Surg 2024:S1058-2746(24)00238-6. [PMID: 38599454 DOI: 10.1016/j.jse.2024.02.036] [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: 12/13/2023] [Revised: 02/10/2024] [Accepted: 02/17/2024] [Indexed: 04/12/2024]
Abstract
BACKGROUND The tripod screw configuration has been shown to offer similar stiffness characteristics to a laterally placed plate. However, concern has been raised that the construct may be prone to failure in scenarios where the screw intersects at the fracture line. We performed a finite element analysis to assess potentially ideal and unideal screw placements in the tripod construct among Mason III radial head fractures. METHODS A 3-dimensional proximal radius model was developed using a computed tomography scan of an adult male radius. The fracture site was simulated with a uniform gap in transverse and sagittal planes creating a Mason type III fracture pattern comprising 3 fragments. Three configurations were modeled with varying screw intersection points in relation to the radial neck fracture line. A fourth configuration comprising an added transverse interfragmentary screw was also modeled. Loading scenarios included axial and shear forces to simulate physiological conditions. Von Mises stress and displacement were used as outcomes for analysis. RESULTS Some variation can be seen among the tripod configurations, with a marginal tendency for reduced implant stress and greater stiffness when screw intersection is further from the neck fracture region. The construct with an added transverse interfragmentary screw demonstrated greater stiffness (2269 N/mm) than an equivalent tripod construct comprising 3 screws (612 N/mm). CONCLUSION The results from this study demonstrate biomechanical similarity between tripod screw constructs including where screws intersect at the radial neck fracture line. An added fourth screw, positioned transversely across fragments, increased construct stiffness in our model.
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Affiliation(s)
- Jared Walker
- University of Queensland, Saint Lucia, QLD, Australia; Herston Biofabrication Institute, Herston, QLD, Australia; Department of Orthopaedic Surgery, The Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia.
| | - Deniz Erbulut
- University of Queensland, Saint Lucia, QLD, Australia; Herston Biofabrication Institute, Herston, QLD, Australia; Department of Orthopaedic Surgery, The Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia
| | - Paul R Rebgetz
- Department of Orthopaedic Surgery, Royal Perth Hospital, Perth, WA, Australia
| | - Fraser J Taylor
- Department of Orthopaedic Surgery, The Gold Coast University Hospital, Gold Coast, QLD, Australia
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France T, Lockwood W, Gu S, Tucker N, Baldini T, Lauder A, Catalano LW. Radiocapitellar and Ulnotrochlear Pressures Increase in a Radial Head Fracture Model: A Cadaveric Biomechanical Analysis. J Bone Joint Surg Am 2024; 106:600-607. [PMID: 38147503 DOI: 10.2106/jbjs.23.00417] [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: 12/28/2023]
Abstract
BACKGROUND Changes in intra-articular pressure have not been previously described in relation to the management of radial head fractures. We hypothesized that pressure within the radiocapitellar and ulnotrochlear joints would increase with progressive radial head resection, mimicking a displaced radial head fracture, in a cadaveric model. METHODS Ten cadaveric specimens were tested. Intra-articular pressure sensors were used to measure pressure within the radiocapitellar and ulnotrochlear joints with the forearm in full supination. The elbow was loaded to 100 N in extension, 45° of flexion, and 90° of flexion under the following conditions: (1) intact radial head, (2) 20% radial head resection, (3) 40% radial head resection, and (4) 100% radial head resection. RESULTS The distribution of pressure between the radiocapitellar and ulnotrochlear joints did not change with sequential, partial resection of the radial head (radiocapitellar joint, between 48.92% and 53.79%; ulnotrochlear joint, between 46.21% and 51.08%). After 20% resection, radiocapitellar peak contact pressure (PCP) increased by 22% (from 1,410 to 1,721.5 kPa) and ulnotrochlear PCP increased by 36% (from 1,319 to 1,797.5 kPa). After 40% resection, radiocapitellar PCP increased by 123% (from 1,410 to 3,145 kPa; p = 0.0003) and ulnotrochlear PCP increased by 105% (from 1,319 to 2,702 kPa; p = 0.007). Ulnotrochlear PCP increased by a total of 159% after complete radial head resection (from 1,319 to 3,415.5 kPa; p = 0.003). CONCLUSIONS Pressures in the radiocapitellar and ulnotrochlear joints were equally distributed with an intact radial head and after partial resection. Radiocapitellar and ulnotrochlear pressures increased with increasing radial head resection, significantly exceeding 100% of normal after radial head resection of 40% of the anterolateral diameter. LEVEL OF EVIDENCE Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.
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Affiliation(s)
- Thomas France
- Department of Orthopedics, University of Colorado, Aurora, Colorado
| | | | - Songyuan Gu
- University of Colorado School of Medicine, Aurora, Colorado
| | - Nick Tucker
- Department of Orthopedics, University of Colorado, Aurora, Colorado
| | - Todd Baldini
- Department of Orthopedics, University of Colorado, Aurora, Colorado
| | - Alexander Lauder
- University of Colorado School of Medicine, Aurora, Colorado
- Department of Orthopedics, Denver Health Medical Center, Denver, Colorado
| | - Louis W Catalano
- Department of Orthopedics, University of Colorado, Aurora, Colorado
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Kahmann SL, Sas A, Große Hokamp N, van Lenthe GH, Müller LP, Wegmann K. A combined experimental and finite element analysis of the human elbow under loads of daily living. J Biomech 2023; 158:111766. [PMID: 37633217 DOI: 10.1016/j.jbiomech.2023.111766] [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: 11/21/2022] [Revised: 08/06/2023] [Accepted: 08/11/2023] [Indexed: 08/28/2023]
Abstract
Elbow trauma is often accompanied by a loss of independence in daily self-care activities, negatively affecting patients' quality of life. Finite element models can help gaining profound knowledge about native human joint mechanics, which is crucial to adequately restore joint functionality after severe injuries. Therefore, a finite element model of the elbow is required that includes both the radio-capitellar and ulno-trochlear joint and is subjected to loads realistic for activities of daily living. Since no such model has been published, we aim to fill this gap. For comparison, 8 intact cadaveric elbows were subjected to loads of up to 1000 N, after they were placed in an extended position. At each load step, the displacement of the proximal humerus relative to the distal base plate was measured with optical tracking markers and the joint pressure was measured with a pressure mapping sensor. Analogously, eight finite element models were created based on subject-specific CT scans of the corresponding elbow specimens. The CT scans were registered to the positions of tantalum beads in the experiment. The optically measured displacements were applied as boundary conditions. We demonstrated that the workflow can predict the experimental contact pressure distribution with a moderate correlation, the experimental peak pressures in the correct joints and the experimental stiffness with moderate to excellent correlation. The predictions of peak pressure magnitude, contact area and load share on the radius require improvement by precise representation of the cartilage geometry and soft tissues in the model, and proper initial contact in the experiment.
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Affiliation(s)
- Stephanie L Kahmann
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Orthopedic and Trauma Surgery, Kerpener Str. 62, Cologne 50937, Germany; Biomechanics Section, Dept. of Mechanical Engineering, KU Leuven, Belgium.
| | - Amelie Sas
- Biomechanics Section, Dept. of Mechanical Engineering, KU Leuven, Belgium
| | - Nils Große Hokamp
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, Germany
| | - G Harry van Lenthe
- Biomechanics Section, Dept. of Mechanical Engineering, KU Leuven, Belgium
| | - Lars-Peter Müller
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Orthopedic and Trauma Surgery, Kerpener Str. 62, Cologne 50937, Germany
| | - Kilian Wegmann
- University of Cologne, Faculty of Medicine and University Hospital Cologne, Center for Orthopedic and Trauma Surgery, Kerpener Str. 62, Cologne 50937, Germany; OCM München, Steinerstr. 6, 81369, München, Deutschland
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Corbaz J, Barimani B, Vauclair F. Early aseptic loosening of a press-fit radial head prosthesis - A case series of 6 patients. J Int Med Res 2023; 51:3000605221135881. [PMID: 37082909 PMCID: PMC10126620 DOI: 10.1177/03000605221135881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023] Open
Abstract
OBJECTIVE Radial head arthroplasty (RHA) is the principal treatment option for comminuted radial head (RH) fractures. Here, we present six cases of failed RHA using a modular monopolar press-fit RHA that was subsequently withdrawn from the market because it was associated with a high incidence of loosening. METHODS We retrospectively collected data from six patients who had received Radial Head Prothesis SystemTM at our centre between July 2015 and June 2016. The average follow-up was 40 months. RESULTS Aseptic loosening of the stem affected five (83%) of the six RHA. Four of these were symptomatic and RHA removal was performed. For these patients, the pain subsided and their elbow range of motion (ROM) improved. CONCLUSION While the ideal design for an RHA is still debatable, RHA is an efficient treatment option that restores elbow stability and function after a comminuted RH fracture. Importantly, removal of the prosthesis is an effective remedy following RHA associated elbow pain and decreased ROM.
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Affiliation(s)
- J Corbaz
- Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, Switzerland
| | - B Barimani
- Department of Orthopaedic Surgery, McGill University, Montreal, Quebec, Canada
| | - F Vauclair
- Bone and Motion Center - Hirslanden, 1006 Lausanne, Switzerland
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Jukes CP, Dirckx M, Phadnis J. Current concepts in distal humeral hemiarthroplasty. J Clin Orthop Trauma 2021; 19:224-230. [PMID: 34150495 PMCID: PMC8190472 DOI: 10.1016/j.jcot.2021.05.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/18/2021] [Accepted: 05/20/2021] [Indexed: 10/21/2022] Open
Abstract
Multi-fragmentary intra-articular fractures of the distal humerus remain a challenge for both patients and surgeons. Open Reduction internal fixation remains the gold standard, however in older patients with comminuted fractures this might not be feasible. There is a growing interest in hemi-arthroplasty as a solution for these cases. However the current experience and follow-up in limited. This review article intends to describe the current concepts in elbow hemiarthroplasty in dept. we will discuss the historical use of these implants, as well as the intricacies of more modern devices. Next we will elaborate an surgical planning, approach, and technical pearls. We will lay out a rehab protocol used by the senior author, and with some considerations for the future.
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Luenam S, Bantuchai T, Kosiyatrakul A, Chanpoo M, Phakdeewisetkul K, Puncreobutr C. Precision of computed tomography and cartilage-reproducing image reconstruction method in generating digital model for potential use in 3D printing of patient-specific radial head prosthesis: a human cadaver study. 3D Print Med 2021; 7:3. [PMID: 33507428 PMCID: PMC7842042 DOI: 10.1186/s41205-021-00093-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 01/10/2021] [Indexed: 11/28/2022] Open
Abstract
Background A prosthetic replacement is a standard treatment for an irreparable radial head fracture; however, the surface mismatch of the commercially available designs is concerned for the long-term cartilage wear. The patient-specific implant created from 3D printing technology could be favorable in replicating the normal anatomy and possibly reduce such sequela. Our study aimed to assess the precision of the computed tomography (CT) and cartilage-reproducing image reconstruction method (CIRM) in generating digital models for potentially use in manufacturing the patient-specific prosthesis from 3D printing. Methods Eight intact elbows (3 right and 5 left) from 7 formalin-embalmed cadavers (4 males and 3 females) with mean age of 83 years (range, 79–94 years) were used for this study. Computerized 3D models were generated from CT, and CIRM. The cartilage-reproducing image reconstruction method has compensated the cartilage profile based on the distance between the subchondral surfaces of the radial head and surrounding bones in CT images. The models of actual radial head geometry used as the gold standard was generated from CT arthrography (CTA). All models of each specimen were matched by registering the surface area of radial neck along with the tuberosity. The difference of head diameter, head thickness, and articular disc depth among three models was evaluated and analyzed by Friedman ANOVA and multiple comparison test using Bonferroni method for statistical correction. A p-value of less than 0.01 was considered statistically significant. The difference of overall 3D geometry was measured with the root mean square of adjacent point pairs. Results The analysis displayed the difference of diameter, thickness, and disc depth across the models (p< 0.01). Pairwise comparisons revealed statistically significant difference of all parameters between CTA models and CT models (p< 0.01) whereas no difference was found between CTA models and CIRM models. The mean difference of overall 3D geometry between CTA models and CT models was 0.51±0.24 mm, and between CTA models and CIRM models was 0.24±0.10 mm. Conclusions CIRM demonstrated encouraging results in reestablish the normal anatomy and could be potentially used in production process of 3D printed patient-specific radial head prosthesis.
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Affiliation(s)
- Suriya Luenam
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand.
| | - Theeraset Bantuchai
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand
| | - Arkaphat Kosiyatrakul
- Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, 315 Ratchawithi Road, Bangkok, 10400, Thailand
| | - Malee Chanpoo
- Department of Anatomy, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | | | - Chedtha Puncreobutr
- Advanced Materials Analysis Research Unit, Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
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Xu GM, Liang ZY, Li W, Yang ZZ, Chen ZB, Zhang J. Finite Element Analysis of Insertion Angle of Absorbable Screws for the Fixation of Radial Head Fractures. Orthop Surg 2020; 12:1710-1717. [PMID: 33000562 PMCID: PMC7767780 DOI: 10.1111/os.12797] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/04/2020] [Accepted: 08/04/2020] [Indexed: 11/28/2022] Open
Abstract
Objective To investigate the biomechanical effects of different insertion angles of absorbable screws for the fixation of radial head fractures. Methods The finite element models used to simulate the fractures were created based on CT scans. Two absorbable screws were used to fix and maintain the stability of the fracture, and the angles between the screws were set to 0°, 15°, 30°, 45°, 60°, 75°, and 90°. A downward force of 100 N was applied at the stress point, which was coupled with the surface, and the distal radius was limited to six degrees of freedom. The direction and location of the applied force were the same in each model. The values of the von Mises stress and peak displacements were calculated. Results Under the applied load and different screw angles, the maximum von Mises stress in the screws was concentrated on the surface contacting the fracture surfaces. The maximum von Mises equivalent stress in the screw decreased when the angle increased from 0° (19.54 MPa) to 45° (13.11 MPa) and increased when the angle further increased to 90° (24.63 MPa). The peak displacement decreased as the angle increased from 0° (0.19 mm) to 45° (0.15 mm) and increased when the angle further increased to 90° (0.25 mm). Conclusion The computational stress distribution showed that fixation with absorbable screws is safe for patients. Moreover, the minimum von Mises stress and displacements were generated when the angle between the screws was 45°; hence, this setting should be recommended for Mason type II radial fractures.
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Affiliation(s)
- Guang-Ming Xu
- Department of Orthopaedics, Shenzhen Pingle Orthopedic Hospital & Shenzhen Pingshan Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Zi-Yang Liang
- First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Wei Li
- Department of Orthopaedics, Shenzhen Pingle Orthopedic Hospital & Shenzhen Pingshan Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Zheng-Zhong Yang
- Department of Orthopaedics, Shenzhen Pingle Orthopedic Hospital & Shenzhen Pingshan Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Zhi-Bin Chen
- Department of Orthopaedics, Shenzhen Pingle Orthopedic Hospital & Shenzhen Pingshan Traditional Chinese Medicine Hospital, Shenzhen, China
| | - Jie Zhang
- Department of Orthopaedics, Shenzhen Pingle Orthopedic Hospital & Shenzhen Pingshan Traditional Chinese Medicine Hospital, Shenzhen, China
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Cucchi D, Luceri F, Celli A, Menon A, Barco R, Wegmann K, Randelli P, Eygendaal D, Arrigoni P. Fracture Pattern Influences Radial Head Replacement Size Determination Among Experienced Elbow Surgeons. Indian J Orthop 2020; 54:539-547. [PMID: 32843951 PMCID: PMC7429655 DOI: 10.1007/s43465-020-00039-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/06/2020] [Indexed: 02/04/2023]
Abstract
BACKGROUND Correct sizing is challenging in radial head replacement and no consensus exists on the implant's optimal height and width to avoid elbow stiffness and instability. Studies exists, suggesting how to appropriately choose the implant size, but the manner by which the fracture pattern influences the surgeons' operative choices was not investigated. METHODS The radial heads of four fresh-frozen cadaveric specimens were excised, measured, and fractured to simulate four patterns: three fragments (A); four fragments (B); comminuted (C); comminuted with bone loss (D). Nine examiners were asked to indicate first the maximum diameter of the radial heads with the help of dedicated sizing dishes and then the appropriate implant size with trial implants. Accuracy and precision were determined. A coefficient of variation was calculated and agreement was evaluated with the Bland-Altman method. RESULTS Accuracy and precision of radial head diameter estimation with dedicated sizing dish were 96.73% and 93.64%, (best pattern, D; worst, C). Accuracy and precision of radial head diameter estimation with trial implants were 99.71% and 90.66% (best pattern, A; worst, D). Frequent modifications occurred between the initial radial head size proposal based on the sizing dish and the radial head size chosen after use of the trial implants (47.2%). CONCLUSIONS Diameter estimation of radial heads with dedicated sizing dishes may be underestimated in comminuted fractures; when bone loss is present, this may lead to an overestimation, especially when using trial implants. Care is essential to determine the optimal size of the implant and to avoid overlenghtening and oversizing, which can be responsible for implant failure. LEVEL OF EVIDENCE Basic Science Study. CLINICAL RELEVANCE Knowledge of the manner by which the fracture pattern influences radial head replacement size estimation can help preventing overlenghtening and oversizing during this procedure.
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Affiliation(s)
- Davide Cucchi
- Department of Orthopaedics and Trauma Surgery, Universitätsklinikum Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany
| | - Francesco Luceri
- IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161 Milan, Italy
- Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
| | - Andrea Celli
- Department of Orthopaedic surgery, Shoulder and Elbow Unit, Hesperia Hospital, Via Arquà, 80/A, 41125 Modena, Italy
| | - Alessandra Menon
- Laboratory of Applied Biomechanics, Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
- U.O.C. 1° Clinica Ortopedica, ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Piazza Cardinal Ferrari 1, 20122 Milan, Italy
- REsearch Center for Adult and Pediatric Rheumatic Diseases (RECAP-RD), Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
| | - Raul Barco
- Shoulder and Elbow Unit, Hospital Universitario La Paz, Paseo de la Castellana 261, Madrid, 28046 Spain
| | - Kilian Wegmann
- Center for Orthopedic and Trauma Surgery, University Medical Center, Cologne, Kerpenerstrasse 62, 50937 Cologne, Germany
| | - Pietro Randelli
- Laboratory of Applied Biomechanics, Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
- U.O.C. 1° Clinica Ortopedica, ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Piazza Cardinal Ferrari 1, 20122 Milan, Italy
- REsearch Center for Adult and Pediatric Rheumatic Diseases (RECAP-RD), Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
| | - Denise Eygendaal
- Department of Orthopaedic Surgery, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Upper Limb Unit, Department of Orthopaedic Surgery, Amphia Hospital, Breda, The Netherlands
| | - Paolo Arrigoni
- Laboratory of Applied Biomechanics, Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
- U.O.C. 1° Clinica Ortopedica, ASST Centro Specialistico Ortopedico Traumatologico Gaetano Pini-CTO, Piazza Cardinal Ferrari 1, 20122 Milan, Italy
- REsearch Center for Adult and Pediatric Rheumatic Diseases (RECAP-RD), Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Mangiagalli 31, 20133 Milan, Italy
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Berkmortel C, Langohr GDG, King G, Johnson J. Hemiarthroplasty implants should have very low stiffness to optimize cartilage contact stress. J Orthop Res 2020; 38:1719-1726. [PMID: 32017162 DOI: 10.1002/jor.24610] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 11/15/2019] [Accepted: 01/21/2020] [Indexed: 02/04/2023]
Abstract
Hemiarthroplasty is often preferred to total arthroplasty as it preserves native tissue; however, accelerated wear of the opposing cartilage is problematic. This is thought to be caused by the stiffness mismatch between the implant and cartilage-bone construct. Reducing the stiffness of the implant by changing the material has been hypothesized as a potential solution. This study employs a finite element model to study a concave-convex hemiarthroplasty articulation for various implant materials (cobalt-chrome, pyrolytic carbon, polyether ether ketone, ultra-high-molecular-weight polyethylene, Bionate-55D, Bionate-75D, and Bionate-80A). The effect of the radius of curvature and the degree of flexion-extension was also investigated to ensure any relationships found between materials were generalizable. The implant material had a significant effect (P < .001) for both contact area and maximum contact pressure on the cartilage surface. All of the materials were different from the native state except for Bionate-80A at two of the different flexion angles. Bionate-80A and Bionate-75D, the materials with the lowest stiffnesses, were the closest to the native state for all flexion angles and radii of curvature. No evident difference between materials occurred unless the modulus was below that of Bionate-55D (288 MPa), suggesting that hemiarthroplasty materials need to be less stiff than this material if they are to protect the opposing cartilage. This is clinically significant as the findings suggest that the development of new hemiarthroplasty implants should use materials with stiffnesses much lower than currently available devices.
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Affiliation(s)
- Carolyn Berkmortel
- Department of Mechanical and Materials Engineering, Western University, London, Ontario, Canada
| | - G Daniel G Langohr
- Department of Mechanical and Materials Engineering, Western University, London, Ontario, Canada.,Bioengineering Laboratory, Roth McFarlane Hand and Upper Limb Centre, Lawson Health Research Institute, St Joseph's Health Care, Western University, Bone and Joint Institute, London, Ontario, Canada.,Department of Surgery, Western University, London, Ontario, Canada
| | - Graham King
- Bioengineering Laboratory, Roth McFarlane Hand and Upper Limb Centre, Lawson Health Research Institute, St Joseph's Health Care, Western University, Bone and Joint Institute, London, Ontario, Canada.,Department of Surgery, Western University, London, Ontario, Canada
| | - James Johnson
- Department of Mechanical and Materials Engineering, Western University, London, Ontario, Canada.,Bioengineering Laboratory, Roth McFarlane Hand and Upper Limb Centre, Lawson Health Research Institute, St Joseph's Health Care, Western University, Bone and Joint Institute, London, Ontario, Canada.,Department of Surgery, Western University, London, Ontario, Canada
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10
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Luenam S, Vongvanichvathana A, Kosiyatrakul A, Kongphanich C, Chanpoo M, Koonchornboon T, Phakdeewisetkul K, Lohwongwatana B, Puncreobutr C. Matching precision of the reverse contralateral radial head in generating of the individualized prosthesis from the surface registration in tuberosity-neck and in tuberosity-diaphysis. J Orthop Surg (Hong Kong) 2020; 27:2309499018821774. [PMID: 30798711 DOI: 10.1177/2309499018821774] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
PURPOSE Following the radial head replacement, the surface mismatches between the implants and the morphological characteristics of the original proximal radius decreased contact areas and increased contact forces which is potential for the long-term articulating cartilage wear. Several studies demonstrated that the individualized prosthesis, created from computed tomographic (CT) images of the contralateral side with the reverse engineering technology, may reduce the mismatch. The aim of this study is to demonstrate the matching precision of the reverse contralateral head between the surface registration in tuberosity-neck (TN) area and in tuberosity-diaphysis (TD) area. MATERIALS AND METHODS High-resolution CT scan of 11 pairs of the cadaveric arms was performed. Utilizing advanced image processing techniques, three-dimensional (3-D) models of each specimen was generated. The model of the left side was reversed and matched with the model of the right side in the same cadaver by registering in the area of radial neck along with tuberosity (TN) and in the area of radial tuberosity combined with 2 cm of proximal diaphysis (TD). The alteration of the head diameter, dish diameter, articular depth, head thickness, end-plane angle, offset, and head volume were evaluated and analyzed by paired t-test. RESULTS No statistically significant difference was found in all parameters from both TN and TD registrations ( p < 0.05). CONCLUSION The surface registration in either TN or TD area can generate the statistically symmetrical 3-D model with the original head. The registration in these areas may possibly be used in creating the individualized radial head prosthesis.
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Affiliation(s)
- Suriya Luenam
- 1 Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Adigun Vongvanichvathana
- 1 Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Arkaphat Kosiyatrakul
- 1 Department of Orthopaedics, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Chutcharn Kongphanich
- 2 Department of Radiology, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Malee Chanpoo
- 3 Department of Anatomy, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Tunyarut Koonchornboon
- 3 Department of Anatomy, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand
| | - Kantapat Phakdeewisetkul
- 4 Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
| | - Boonrat Lohwongwatana
- 4 Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
| | - Chedtha Puncreobutr
- 4 Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand
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Hemmingsen CK, Thillemann TM, Elmengaard B, de Raedt S, Nielsen ET, Mosegaard SB, Stentz-Olesen K, Stilling M. Elbow Biomechanics, Radiocapitellar Joint Pressure, and Interosseous Membrane Strain Before and After Radial Head Arthroplasty. J Orthop Res 2020; 38:510-522. [PMID: 31595550 DOI: 10.1002/jor.24488] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 09/17/2019] [Indexed: 02/04/2023]
Abstract
Complex radial head fracture and elbow instability can be treated with radial head arthroplasty. Good clinical results have been described after this surgical treatment. However, the revision and complication rate reported in the literature is concerning. This might be due to altered kinematics after radial head arthroplasty. Eight human native elbows were examined with dynamic radiostereometric analysis and compared with a radial head arthroplasty. Translations of the radial head in the x-, y-, and z-directions relative to the humerus and the ulna were measured. The radiocapitellar joint pressure was measured using a pressure sensor. The tension within the interosseous membrane was measured using a custom-made strain gauge. After radial head arthroplasty, the radial head was displaced approximately 1.8 mm medially and 1.4 mm distally at the starting point. During unloaded flexion motion the difference in all translations between the native radial head and the radial head arthroplasty was less than 1 mm (95% confidence interval [CI] ± 0.5 mm) (p = 0.001). With loading the difference was less than 1.5 mm (95% CI ± 1.5 mm) (p = 0.001). The mean difference in radiocapitellar joint contact pressure was less than 0.30 MPa (95% CI ± 0.40 MPa) (p = 0.001) during unloaded flexion motion. There were only submillimetre kinematic changes and small changes in joint pressure and interosseous membrane tension after the insertion of a radial head arthroplasty in an experimental setting. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:510-522, 2020.
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Affiliation(s)
- Chalotte K Hemmingsen
- Department of Clinical Medicine, Aarhus University, Groennehaven 25, 8520 Lystrup, Aarhus, Denmark.,Orthopedic Research Unit, Aarhus University Hospital, Aarhus, Denmark
| | - Theis M Thillemann
- Department of Orthopedic Surgery, Shoulder and Elbow Section, Aarhus University Hospital, Aarhus, Denmark
| | - Brian Elmengaard
- Department of Orthopedic Surgery, Shoulder and Elbow Section, Aarhus University Hospital, Aarhus, Denmark
| | | | - Emil T Nielsen
- Department of Clinical Medicine, Aarhus University, Groennehaven 25, 8520 Lystrup, Aarhus, Denmark.,Orthopedic Research Unit, Aarhus University Hospital, Aarhus, Denmark.,Department of Orthopedic Surgery, Hand Section, Aarhus University Hospital, Aarhus, Denmark
| | - Sebastian B Mosegaard
- Department of Clinical Medicine, Aarhus University, Groennehaven 25, 8520 Lystrup, Aarhus, Denmark.,Department of Orthopedic Surgery, Hand Section, Aarhus University Hospital, Aarhus, Denmark
| | | | - Maiken Stilling
- Department of Clinical Medicine, Aarhus University, Groennehaven 25, 8520 Lystrup, Aarhus, Denmark.,Orthopedic Research Unit, Aarhus University Hospital, Aarhus, Denmark.,Department of Orthopedic Surgery, Hand Section, Aarhus University Hospital, Aarhus, Denmark
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12
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Szmit J, King GJW, Johnson JA, Langohr GDG. The effect of stem fit on the radiocapitellar contact mechanics of a metallic axisymmetric radial head hemiarthroplasty: is loose fit better than rigidly fixed? J Shoulder Elbow Surg 2019; 28:2394-2399. [PMID: 31371158 DOI: 10.1016/j.jse.2019.05.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 02/01/2023]
Abstract
BACKGROUND Radial head hemiarthroplasty is commonly used to manage comminuted displaced fractures. Regarding implant fixation, current designs vary, with some prostheses aiming to achieve a tight "fixed" fit and others using a smooth stem with an over-reamed "loose" fit. The purpose of this study was to evaluate the effect of radial head hemiarthroplasty stem fit on radiocapitellar contact using a finite element model that simulated both fixed (size-for-size) and loose (1-, 2-, and 3-mm over-reamed) stem fits. It was hypothesized that a loose stem fit would improve radiocapitellar contact mechanics, with an increased contact area and decreased contact stress, by allowing the implant to find its "optimal" position with respect to the capitellum. METHODS Finite element models of the elbow were produced to compare the effects of stem fit on radiocapitellar contact of a metallic axisymmetric radial head implant. Radiocapitellar contact mechanics (contact area and maximum contact stress) were computed for 0°, 45°, 90°, and 135° of elbow flexion with the forearm in neutral rotation, pronation, and supination. RESULTS The data suggest that the loose smooth stem radial head implant may be functioning like a bipolar implant in optimizing radiocapitellar contact. Over-reaming of 3 mm produced a larger amount of stress concentration on the capitellum, suggesting there may be a limit to how loose a smooth stem implant should be implanted. CONCLUSIONS The loose 1 to 2 mm over-reamed stem provided optimal contact mechanics of the metallic axisymmetric radial head implant compared with the fixed stem.
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13
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Wegmann K, Knowles N, Lalone E, Müller LP, Athwal GS, King GJW. Computed Tomography Analysis of the Radial Notch of the Ulna. J Hand Surg Am 2019; 44:794.e1-794.e8. [PMID: 30502012 DOI: 10.1016/j.jhsa.2018.10.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 08/19/2018] [Accepted: 10/09/2018] [Indexed: 02/02/2023]
Abstract
PURPOSE The anatomy of the radial head and capitellum has been extensively studied; however, the anatomy of the radial notch of the ulna (RNU) has received little attention. This imaging-based anatomic study characterizes the morphology of the RNU. METHODS Ninety-eight cadaveric arms (57 male, 72 ± 14 y) were imaged with computed tomography, and 3-dimensional reconstructions of the proximal ulna were constructed. The anteroposterior and proximal-distal dimensions of the RNU as well as the radius of curvature at standardized levels were measured in 2-mm increments. The orientation of the RNU was also determined. RESULTS The proximal-distal and anteroposterior dimensions of the RNU were 12 ± 2 mm (range, 7-16 mm) and 18 ± 3 mm (range, 12-24 mm), respectively. The average radius of curvature of the RNU was 15 ± 0 mm (range, 15-16 mm). The radius of curvature did not change significantly when comparing the proximal and distal aspect of the RNU. The RNU was rotated 33° ± 2° (range, 31° to 38°) externally relative to the transverse plane of the ulna. The average depth of the RNU at its deepest point was 2.2 ± 0.4 mm (range, 1.5-2.7 mm). The depth decreased from proximal to distal, being most shallow distally. The depth changed by an increase of the radius of curvature, as well as by rotation in the frontal plane. CONCLUSIONS The RNU anatomy was variable, generally extending laterally from proximal to distal. This suggests that a radial head implant should taper from proximal to distal to optimize contact at the RNU. CLINICAL RELEVANCE The present study investigates the detailed anatomy of the radial notch of the ulna using computed tomography scans. The data might help improve the design of prosthetic components.
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Affiliation(s)
- Kilian Wegmann
- Center for Orthopedic and Trauma Surgery, University Medical Center of Cologne, Cologne, Germany.
| | - Nikolas Knowles
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
| | - Emily Lalone
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
| | - Lars P Müller
- Center for Orthopedic and Trauma Surgery, University Medical Center of Cologne, Cologne, Germany
| | - George S Athwal
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
| | - Graham J W King
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
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14
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Sun Y, Hong H, Adikrishna A, Kim YJ, Jeon IH. Contact Mechanics of Anatomic Radial Head Prosthesis: Comparison Between Native Radial Head and Anatomic Radial Head Prostheses in the Dynamic Mode. J Hand Surg Am 2019; 44:517.e1-517.e7. [PMID: 30292716 DOI: 10.1016/j.jhsa.2018.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 06/26/2018] [Accepted: 08/08/2018] [Indexed: 02/02/2023]
Abstract
PURPOSE The biomechanical characteristics of anatomic radial head prostheses have not been completely investigated. We compared and analyzed the contact kinematic characteristics of the native radial head and radial head prostheses replicating the native head contour, using a real-time flexion simulation model. METHODS Ten fresh-frozen cadavers were used in this pilot study. A simulating dynamic motion mode from 0° to 130° of elbow flexion was applied. Radiocapitellar contact pressure and area were measured using a real-time digitized pressure sensor. Further, contact area and pressure curves were obtained during flexion, using a motion-tracking device. RESULTS The mean contact area, mean contact pressure, and peak contact pressure of the native radial head and radial head prosthesis were 39 mm2, 0.0078 kgf/mm2, 0.0123 kgf/mm2, and 33 mm2, 0.0093 kgf/dm2, 0.0148 kgf/mm2, respectively. The contact area and pressure curves were parabolic nonlinear for the radial head prosthesis and more linear for the native radial head. CONCLUSIONS The radial head prosthesis mimics the mechanics of the native radial head in terms of mean contact area, mean contact pressure, and peak contact pressure; however, different patterns of contact pressure and area curves during elbow flexion-extension were observed. CLINICAL RELEVANCE We found that the biomechanics of the anatomic radial head prostheses used in the study were similar to those of the native radial head.
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Affiliation(s)
- Yucheng Sun
- Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Hanpyo Hong
- Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Arnold Adikrishna
- Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Yoon-Jeong Kim
- Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - In-Ho Jeon
- Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
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Sun Y, Adikrishna A, Hong H, Tan J, Jeon IH. Comparison of the biomechanics of radial head prostheses with dynamic loading in the radiocapitellar joint. J Hand Surg Eur Vol 2019; 44:408-413. [PMID: 30744462 DOI: 10.1177/1753193419825526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We used eight fresh cadaveric elbows to evaluate the biomechanical characteristics of the native radial head, an anatomic radial head prosthesis, and a non-anatomic radial head prosthesis using a dynamic model. The biceps, brachialis, and triceps were attached to pneumatic actuators loaded to mimic muscle force. The radiocapitellar contact pressure and area were measured in real time, and the associated curves were depicted simultaneously. No significant differences in the contact area or associated curves were found between native radial head and the anatomic radial head prosthesis. The contact pressure and associated curve for the anatomic radial head prosthesis were better than those for the non-anatomic radial head prosthesis. We conclude from this study that the contact pressure and area of the elbow with anatomic radial head prosthesis are similar to those of the native radial head. The anatomic radial head prosthesis appears to be more suitable in clinical use.
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Affiliation(s)
- Yucheng Sun
- 1 Department of Orthopaedic Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.,2 Department of Hand Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - Arnold Adikrishna
- 1 Department of Orthopaedic Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Hanpyo Hong
- 1 Department of Orthopaedic Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
| | - Jun Tan
- 2 Department of Hand Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - In-Ho Jeon
- 1 Department of Orthopaedic Surgery, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea
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Abstract
OBJECTIVE To evaluate the effect of intentional undersizing of prosthetic radial head implant diameters on joint contact pressures. METHODS Eight fresh-frozen cadaveric elbows were aligned in neutral extension and loaded with 100 N using a custom testing apparatus. Radiocapitellar contact pressures were recorded using a Tekscan thin-film pressure sensor. Prosthetic radial head replacement was performed with 2 prostheses: the Anatomic Radial Head and the Evolve Proline Radial Head prostheses. Each design was sized according to the manufacturer's recommendations and then again using 2-mm smaller radial heads. RESULTS Average and peak pressures were significantly higher with the Evolve than the Anatomic prostheses (P < 0.03 and 0.02, respectively). Peak pressures decreased from 4.2 ± 0.5 MPa to 2.9 ± 0.3 MPa for the Anatomic Radial Heads and from 5.6 ± 0.5 MPa to 3.9 ± 0.6 MPa when the Evolve Radial Heads were undersized by 2 mm. The mean pressures of the Anatomic Radial Heads (1.4 ± 0.1 MPa) did not change significantly with undersizing (1.3 ± 0.1 MPa, P = 0.12), whereas the mean pressures of the Evolve Radial Heads (1.6 ± 0.1 MPa) were significantly reduced with undersizing (1.4 ± 0.1 MPa, P < 0.02). CONCLUSION Both mean and peak pressures were initially high for the Evolve Radial Head sized based on the short axis diameter and were improved with further undersizing by 2 mm. Peak, but not mean, contact pressures were improved by undersizing the Anatomic prosthesis based on the long axis diameter. CLINICAL RELEVANCE These findings support the clinical recommendation of some surgeons to undersize the Evolve prosthesis by 2-mm smaller diameter than the current manufacturer's suggestion and give reason to consider doing the same for the Anatomic prosthesis.
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Abstract
The principal goal of the FEBio project is to provide an advanced finite element tool for the biomechanics and biophysics communities that allows researchers to model mechanics, transport, and electrokinetic phenomena for biological systems accurately and efficiently. In addition, because FEBio is geared toward the research community, the code is designed such that new features can be added easily, thus making it an ideal tool for testing novel computational methods. Finally, because the success of a code is determined by its user base, integral goals of the FEBio project have been to offer support and outreach to our community; to provide mechanisms for dissemination of results, models, and data; and to encourage interaction between users. This review presents the history of the FEBio project, from its initial developments through its current funding period. We also present a glimpse into the future of FEBio.
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Affiliation(s)
- Steve A Maas
- Department of Bioengineering and Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, Utah 84112;
| | - Gerard A Ateshian
- Department of Mechanical Engineering and Department of Biomedical Engineering, Columbia University, New York, New York 10027
| | - Jeffrey A Weiss
- Department of Bioengineering and Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, Utah 84112; .,Department of Orthopedics, University of Utah, Salt Lake City, Utah 84112
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Langohr GDG, Willing R, Medley JB, King GJW, Johnson JA. The Effect of Radial Head Hemiarthroplasty Geometry on Proximal Radioulnar Joint Contact Mechanics. J Hand Surg Am 2016; 41:745-52. [PMID: 27241850 DOI: 10.1016/j.jhsa.2016.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Revised: 01/19/2016] [Accepted: 05/01/2016] [Indexed: 02/02/2023]
Abstract
PURPOSE To compare the joint contact area and peak contact stress of different radial head (RH) hemiarthroplasty articular profiles for the proximal radioulnar joint (PRUJ) to the native radial head with the hypothesis that the side radius and side angle closest to the native mating ulnar articular profile would provide the best contact mechanics. METHODS Finite element models generated from the computed tomography geometry of 14 native elbows (73 ± 17.5 years) were subjected to 12 different RH profiles having varying side radii (flat [r = ∞ mm], 16.25, 8.12, and 4.50 mm) and side angles (0°, 5°, and 10°) under a constant compressive 20-N medial load. Contact areas and peak contact stresses were computed and compared with the native joint. RESULTS On average, RH implants significantly reduced PRUJ contact area by 55% ± 16% and increased peak contact stress by 337% ± 241% compared with the native RH. The prosthesis side radius had significant effects on both contact area and stress, but side angle did not. The 16.25-mm radii produced the largest contact areas, and the 4.50-mm radius model generated the smallest contact areas. As the side radius was decreased, peak contact stress was reduced as the contact migrated toward the center of the native ulnar articulation, although the 8.12-mm radius achieved the lowest peak contact stress. CONCLUSIONS Whereas RH hemiarthroplasty side radius can affect both contact area and peak contact stress, the magnitude of the effect on contact area is relatively small compared with that of the peak contact stress. Furthermore, although a flat RH side profile with a side angle of 5° more closely matched the side profile of the native ulnas used in the present study, the optimal profile was found to be a smaller radius of 8.12 mm. CLINICAL RELEVANCE Optimizing PRUJ contact mechanics after metallic RH hemiarthroplasty may contribute to better clinical outcomes by reducing the potential for native cartilage degeneration.
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Affiliation(s)
- G Daniel G Langohr
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
| | - Ryan Willing
- Binghamton University, State University of New York, Binghamton, NY
| | | | - Graham J W King
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada
| | - James A Johnson
- Roth
- McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, Ontario, Canada.
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Phadnis J, Watts AC, Bain GI. Elbow hemiarthroplasty for the management of distal humeral fractures: current technique, indications and results. Shoulder Elbow 2016; 8:171-83. [PMID: 27583016 PMCID: PMC4950283 DOI: 10.1177/1758573216640210] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/25/2016] [Indexed: 11/16/2022]
Abstract
There has been a growing recent interest in the use of elbow hemiarthroplasty for the treatment of distal humeral trauma in select patients. However, the current available evidence regarding outcome after elbow hemiarthroplasty is limited to case series and biomechanical data. Consequently, the procedure remains unfamiliar to many surgeons. The aim of the present review is to outline the evidence regarding elbow hemiarthroplasty and to use this, along with the author's experience, to better describe the indications, surgical technique and outcomes after this procedure.
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Affiliation(s)
- Joideep Phadnis
- Department of Orthopaedics, Brighton and Sussex University Hospitals, Brighton, UK,Joideep Phadnis, 70 Nevill Avenue, Hove, East Sussex BN3 7NA, UK. Tel: +44 (0)7496853014.
| | - Adam C Watts
- Upper Limb Unit, Wrightington Hospital, Wigan, UK
| | - Gregory I Bain
- Department of Orthopaedics, Flinders University, Bedford Park, SA, South Australia
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Willing R, King GJ, Johnson JA. Contact mechanics of reverse engineered distal humeral hemiarthroplasty implants. J Biomech 2015; 48:4037-4042. [DOI: 10.1016/j.jbiomech.2015.09.047] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 08/27/2015] [Accepted: 09/27/2015] [Indexed: 11/29/2022]
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