1
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Sanders JE, Vamos AC, Mertens JC, Allyn KJ, Larsen BG, Ballesteros D, Wang H, DeGrasse NS, Garbini JL, Hafner BJ, Friedly JL. An adaptive prosthetic socket for people with transtibial amputation. Sci Rep 2024; 14:11168. [PMID: 38750086 PMCID: PMC11096356 DOI: 10.1038/s41598-024-61234-9] [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: 01/20/2024] [Accepted: 05/01/2024] [Indexed: 05/18/2024] Open
Abstract
It is essential that people with limb amputation maintain proper prosthetic socket fit to prevent injury. Monitoring and adjusting socket fit, for example by removing the prosthesis to add prosthetic socks, is burdensome and can adversely affect users' function and quality-of-life. This study presents results from take-home testing of a motor-driven adaptive socket that automatically adjusted socket size during walking. A socket fit metric was calculated from inductive sensor measurements of the distance between the elastomeric liner surrounding the residual limb and the socket's inner surface. A proportional-integral controller was implemented to adjust socket size. When tested on 12 participants with transtibial amputation, the controller was active a mean of 68% of the walking time. In general, participants who walked more than 20 min/day demonstrated greater activity, less doff time, and fewer manual socket size adjustments for the adaptive socket compared with a locked non-adjustable socket and a motor-driven socket that participants adjusted with a smartphone application. Nine of 12 participants reported that they would use a motor-driven adjustable socket if it were available as it would limit their socket fit issues. The size and weight of the adaptive socket were considered the most important variables to improve.
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Affiliation(s)
- Joan E Sanders
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA.
| | - Andrew C Vamos
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Joseph C Mertens
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Daniel Ballesteros
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Horace Wang
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Nicholas S DeGrasse
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA, 98195, USA
| | - Joseph L Garbini
- Department of Mechanical Engineering, University of Washington, 3900 E Stevens Way NE, Box 352600, Seattle, WA, 98195, USA
| | - Brian J Hafner
- Department of Rehabilitation Medicine, University of Washington, 1959 NE Pacific St, Box 356490, Seattle, WA, 98195, USA
| | - Janna L Friedly
- Department of Rehabilitation Medicine, University of Washington, 325 Ninth Ave, Box 359612, Seattle, WA, 98104, USA
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2
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Lee KH, Heo HS, Kim J, Cho JH, Kim KT, Hur JY, Kim JH, Lee Y. A Pneumatically Controlled Prosthetic Socket for Transfemoral Amputees. SENSORS (BASEL, SWITZERLAND) 2023; 24:133. [PMID: 38202994 PMCID: PMC10780925 DOI: 10.3390/s24010133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 12/15/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024]
Abstract
Amputees typically experience changes in residual limb volume in their daily lives. It causes an uncomfortable fit of the socket by applying high pressure on the sensitive area of the residual limb or by loosening the socket. In this study, we developed a transfemoral prosthetic socket for above-the-knee amputees that ensures a good socket fit by maintaining uniform and constant contact pressure despite volume changes in the residual limb. The socket has two air bladders in the posterior femoral region, and the pneumatic controller is located on the tibia of the prosthesis. The pneumatic system aims to minimize unstable fitting of the socket and improve walking performance by inflating or deflating the air bladder. The developed socket autonomously maintains the air pressure inside the prosthetic socket at a steady-state error of 3 mmHg or less by adjusting the amount of air in the air bladder via closed-loop control. In the clinical trial, amputee participants walked on flat and inclined surfaces. The displacement between the residual limb and socket during the gait cycle was reduced by up to 33.4% after air injection into the socket. The inflatable bladder increased the knee flexion angle on the affected side, resulting in increased stride length and gait velocity. The pneumatic socket provides a stable and comfortable walking experience not only when walking on flat ground but also on slopes.
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Affiliation(s)
- Kang-Ho Lee
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea; (J.K.); (Y.L.)
| | - Hyun-Seok Heo
- Shinsegae Prosthetic Center, Daegu 41710, Republic of Korea; (H.-S.H.); (J.-Y.H.)
| | - Jeongmin Kim
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea; (J.K.); (Y.L.)
| | - Jang Hyuk Cho
- Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu 42601, Republic of Korea; (J.H.C.); (K.T.K.)
| | - Kyoung Tae Kim
- Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu 42601, Republic of Korea; (J.H.C.); (K.T.K.)
| | - Jeong-Yong Hur
- Shinsegae Prosthetic Center, Daegu 41710, Republic of Korea; (H.-S.H.); (J.-Y.H.)
| | - Jang Hwan Kim
- Department of Rehabilitation Technology, Graduate School of Hanseo University, Seosan 31962, Republic of Korea;
| | - Yongkoo Lee
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea; (J.K.); (Y.L.)
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Baldock M, Pickard N, Prince M, Kirkwood S, Chadwell A, Howard D, Dickinson A, Kenney L, Gill N, Curtin S. Adjustable prosthetic sockets: a systematic review of industrial and research design characteristics and their justifications. J Neuroeng Rehabil 2023; 20:147. [PMID: 37926807 PMCID: PMC10626671 DOI: 10.1186/s12984-023-01270-0] [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: 07/13/2023] [Accepted: 10/18/2023] [Indexed: 11/07/2023] Open
Abstract
BACKGROUND The prosthetic socket is a key component that influences prosthesis satisfaction, with a poorly fitting prosthetic socket linked to prosthesis abandonment and reduced community participation. This paper reviews adjustable socket designs, as they have the potential to improve prosthetic fit and comfort through accommodating residual limb volume fluctuations and alleviating undue socket pressure. METHODS Systematic literature and patent searches were conducted across multiple databases to identify articles and patents that discussed adjustable prosthetic sockets. The patents were used to find companies, organisations, and institutions who currently sell adjustable sockets or who are developing devices. RESULTS 50 literature articles and 63 patents were identified for inclusion, representing 35 different designs used in literature and 16 commercially available products. Adjustable sockets are becoming more prevalent with 73% of publications (literature, patents, and news) occurring within the last ten years. Two key design characteristics were identified: principle of adjustability (inflatable bladders, moveable panels, circumferential adjustment, variable length), and surface form (conformable, rigid multi-DOF, and rigid single DOF). Inflatable bladders contributed to 40% of literature used designs with only one identified commercially available design (n = 16) using this approach. Whereas circumferential adjustment designs covered 75% of identified industry designs compared to only 36% of literature devices. Clinical studies were generally small in size and only 17.6% of them assessed a commercially available socket. DISCUSSION There are clear differences in the design focus taken by industry and researchers, with justification for choice of design and range of adjustment often being unclear. Whilst comfort is often reported as improved with an adjustable socket, the rationale behind this is not often discussed, and small study sizes reduce the outcome viability. Many adjustable sockets lack appropriate safety features to limit over or under tightening, which may present a risk of tissue damage or provide inadequate coupling, affecting function and satisfaction. Furthermore, the relationship between design and comfort or function are rarely investigated and remain a significant gap in the literature. Finally, this review highlights the need for improved collaboration between academia and industry, with a strong disconnect observed between commercial devices and published research studies.
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Affiliation(s)
- Michael Baldock
- School of Health and Society at the University of Salford, Salford, UK.
| | - Nicolaas Pickard
- School of Health and Society at the University of Salford, Salford, UK.
| | - Michael Prince
- School of Health and Society at the University of Salford, Salford, UK
| | - Sarah Kirkwood
- School of Health and Society at the University of Salford, Salford, UK
| | - Alix Chadwell
- School of Health and Society at the University of Salford, Salford, UK
- School of Engineering at Newcastle University, Newcastle upon Tyne, UK
| | - David Howard
- School of Health and Society at the University of Salford, Salford, UK
| | - Alex Dickinson
- School of Engineering at the University of Southampton, Southampton, UK
| | - Laurence Kenney
- School of Health and Society at the University of Salford, Salford, UK
| | - Niamh Gill
- School of Health and Society at the University of Salford, Salford, UK
| | - Sam Curtin
- School of Health and Society at the University of Salford, Salford, UK.
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González AK, Rodríguez-Reséndiz J, Gonzalez-Durán JEE, Olivares Ramírez JM, Estévez-Bén AA. Development of a Hip Joint Socket by Finite-Element-Based Analysis for Mechanical Assessment. Bioengineering (Basel) 2023; 10:bioengineering10020268. [PMID: 36829762 PMCID: PMC9952638 DOI: 10.3390/bioengineering10020268] [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: 01/09/2023] [Revised: 02/04/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
This article evaluates a hip joint socket design by finite element method (FEM). The study was based on the needs and characteristics of a patient with an oncological amputation; however, the solution and the presented method may be generalized for patients with similar conditions. The research aimed to solve a generalized problem, taking a typical case from the study area as a reference. Data were collected on the use of the current improving prosthesis-specifically in interaction with its socket-to obtain information on the new approach design: this step constituted the work's starting point, where the problems to be solved in conventional designs were revealed. Currently, the development of this type of support does not consider the functionality and comfort of the patient. Research has reported that 58% of patients with sockets have rejected their use, because they do not fit comfortably and functionally; therefore, patients' low acceptance or rejection of the use of the prosthesis socket has been documented. In this study, different designs were evaluated, based on the FEM as scientific support for the results obtained, for the development of a new ergonomic fit with a 60% increase in patient compliance, that had correct gait performance when correcting postures, improved fit-user interaction, and that presented an esthetic fit that met the usability factor. The validation of the results was carried out through the physical construction of the prototype. The research showed how the finite element method improved the design, analyzing the structural behavioral, and that it could reduce cost and time instead of generating several prototypes.
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Affiliation(s)
- Ana Karen González
- Engineering Faculty, Universidad Autónoma de Querétaro, Querétaro 76010, Mexico
| | - Juvenal Rodríguez-Reséndiz
- Engineering Faculty, Universidad Autónoma de Querétaro, Querétaro 76010, Mexico
- Correspondence: (J.R.-R.); (J.M.O.R.)
| | | | - Juan Manuel Olivares Ramírez
- Department of Renewable Energy, Universidad Tecnológica de San Juan del Río, Querétaro 76800, Mexico
- Correspondence: (J.R.-R.); (J.M.O.R.)
| | - Adyr A. Estévez-Bén
- Engineering Faculty, Universidad Autónoma de Querétaro, Querétaro 76010, Mexico
- Chemistry Faculty, Universidad Autónoma de Querétaro, Querétaro 76010, Mexico
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5
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Paternò L, Lorenzon L. Soft robotics in wearable and implantable medical applications: Translational challenges and future outlooks. Front Robot AI 2023; 10:1075634. [PMID: 36845334 PMCID: PMC9945115 DOI: 10.3389/frobt.2023.1075634] [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: 10/20/2022] [Accepted: 01/17/2023] [Indexed: 02/11/2023] Open
Abstract
This work explores the recent research conducted towards the development of novel classes of devices in wearable and implantable medical applications allowed by the introduction of the soft robotics approach. In the medical field, the need for materials with mechanical properties similar to biological tissues is one of the first considerations that arises to improve comfort and safety in the physical interaction with the human body. Thus, soft robotic devices are expected to be able of accomplishing tasks no traditional rigid systems can do. In this paper, we describe future perspectives and possible routes to address scientific and clinical issues still hampering the accomplishment of ideal solutions in clinical practice.
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Affiliation(s)
- Linda Paternò
- The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy,Department of Excellence in Robotics and AI, Scuola Superiore Sant’Anna, Pisa, Italy,*Correspondence: Linda Paternò,
| | - Lucrezia Lorenzon
- The BioRobotics Institute, Scuola Superiore Sant’Anna, Pisa, Italy,Department of Excellence in Robotics and AI, Scuola Superiore Sant’Anna, Pisa, Italy
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6
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Coburn KA, DeGrasse NS, Allyn KJ, Larsen BG, Garbini JL, Sanders JE. Using magnetic panels to enlarge a transtibial prosthetic socket. Med Eng Phys 2022; 110:103924. [PMID: 36564131 DOI: 10.1016/j.medengphy.2022.103924] [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: 03/25/2022] [Revised: 10/10/2022] [Accepted: 11/15/2022] [Indexed: 11/18/2022]
Abstract
A novel method is described to connect a prosthetic liner to the panels of an adjustable socket to facilitate limb fluid volume stabilization in prosthesis users. Magnets are placed in the socket panels, and iron powder is embedded in the user's prosthetic liner. When the magnet is in close proximity to the liner, a firm connection is formed. The system's capability to execute panel pull on transtibial prosthesis users was tested. The backs of the panels were supported by a bracket mounted to the external surface of the socket that allowed the radial position of the panels to be adjusted. Bench testing demonstrated an optimized strength-to-weight ratio using 1.27-cm thick annular-shaped magnets supported by 0.32-cm thick backplates. Testing on four people with transtibial amputation showed that the maximum socket increase achieved using magnetic panel pull ranged from 5.3% to 13.8% of the initial (panels flush) socket volume. The results indicate that magnetic panel pull induces a meaningful increase in socket volume during sitting. The clinical relevance is a novel strategy that may help stabilize prosthesis users' limb fluid volume over the day.
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Affiliation(s)
- Kendrick A Coburn
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, United States
| | - Nicholas S DeGrasse
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, United States
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, United States
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, United States
| | - Joseph L Garbini
- Department of Mechanical Engineering, University of Washington, Seattle, WA, 98195, United States
| | - Joan E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, 98195, United States.
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7
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Mertens JC, Brzostowski JT, Vamos A, Allyn KJ, Hafner BJ, Friedly JL, DeGrasse NS, Ballesteros D, Krout A, Larsen BG, Garbini JL, Sanders JE. A novel portable sensor to monitor bodily positions and activities in transtibial prosthesis users. Clin Biomech (Bristol, Avon) 2022; 99:105741. [PMID: 36041309 PMCID: PMC10545288 DOI: 10.1016/j.clinbiomech.2022.105741] [Citation(s) in RCA: 4] [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: 01/27/2022] [Revised: 07/22/2022] [Accepted: 08/12/2022] [Indexed: 02/07/2023]
Abstract
BACKGROUND Step activity monitors provide insight into the amount of physical activity prosthesis users conduct but not how they use their prosthesis. The purpose of this research was to help fill this void by developing and testing a technology to monitor bodily position and type of activity. METHODS Thin inductive distance sensors were adhered to the insides of sockets of a small group of transtibial prosthesis users, two at proximal locations and two at distal locations. An in-lab structured protocol and a semi-structured out-of-lab protocol were video recorded, and then participants wore the sensing system for up to 7 days. A data processing algorithm was developed to identify sit, seated shift, stand, standing weight-shift, walk, partial doff, and non-use. Sensed distance data from the structured and semi-structured protocols were compared against the video data to characterize accuracy. Bodily positions and activities during take-home testing were tabulated to characterize participants' use of the prosthesis. FINDINGS Sit and walk detection accuracies were above 95% for all four participants tested. Stand detection accuracy was above 90% for three participants and 62.5% for one participant. The reduced accuracy may have been due to limited stand data from that participant. Step count was not proportional to active use time (sum of stand, walk, and standing weight-shift times). INTERPRETATION Step count may provide an incomplete picture of prosthesis use. Larger studies should be pursued to investigate how bodily position and type of activity may facilitate clinical decision-making and improve the lives of people with lower limb amputation.
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Affiliation(s)
- Joseph C Mertens
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Jacob T Brzostowski
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Andrew Vamos
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Brian J Hafner
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA 98195, USA
| | - Janna L Friedly
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA 98195, USA
| | - Nicholas S DeGrasse
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Daniel Ballesteros
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Adam Krout
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Joseph L Garbini
- Department of Mechanical Engineering, University of Washington, Seattle, WA 98195, USA
| | - Joan E Sanders
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA 98195, USA.
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8
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Rich TL, Voss G, Fairhurst S, Matsumoto M, Brielmaier S, Koester K, Netoff TI, Hansen AH, Ferguson JE. Feasibility testing of a novel prosthetic socket sensor system. Disabil Rehabil 2022:1-8. [PMID: 35797711 DOI: 10.1080/09638288.2022.2093997] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE Poorly fitting prosthetic sockets contribute to decreased quality of life, health, and well-being for persons with amputations. Therefore, improved socket fit is a high clinical priority. METHODS In this study, we describe the design and testing of a novel sensor system that can be incorporated into a prosthetic socket to measure distal end weight bearing in the socket and can alert a prosthesis user if poor socket fit is suspected. We present the results of testing this device with three Veterans who were new prosthesis users and three Veterans who were experienced prosthesis users. RESULTS AND CONCLUSIONS We collected sensor data during walking trials while participants wore varying numbers of sock plies and qualitative feedback on the design of the socket fit sensor system. For analysis, peak sensor measurements during walking cycles were identified and combined with socket fit data (i.e., a clinician-determined level of "good," "too tight," or "too loose" and the number of sock ply worn each trial). We found consistent relationships between peak sensor measurements and socket fit in our sample. Also, all users expressed an interest in the device, highlighting its potential benefits during early prosthesis training.Implications for RehabilitationEnsuring socket fit is challenging for many prosthesis users.A novel wearable sensor system can be used to identify socket fit issues for some prosthesis users.This type of system could be most helpful for new prosthesis users and those with sensory and cognitive challenges.
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Affiliation(s)
- Tonya L Rich
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America.,Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Greg Voss
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America
| | - Stuart Fairhurst
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America
| | - Mary Matsumoto
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America.,Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Steven Brielmaier
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America
| | - Karl Koester
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America
| | - Theoden I Netoff
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Andrew H Hansen
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America.,Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America.,Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - John E Ferguson
- Minneapolis VA Health Care System, Minneapolis, Minnesota, United States of America.,Department of Rehabilitation Medicine, University of Minnesota, Minneapolis, Minnesota, United States of America
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9
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Zhu W, Chen Y, Ko ST, Lu Z. Redundancy Reduction for Sensor Deployment in Prosthetic Socket: A Case Study. SENSORS (BASEL, SWITZERLAND) 2022; 22:3103. [PMID: 35590792 PMCID: PMC9105868 DOI: 10.3390/s22093103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/12/2022] [Accepted: 04/16/2022] [Indexed: 06/15/2023]
Abstract
The irregular pressure exerted by a prosthetic socket over the residual limb is one of the major factors that cause the discomfort of amputees using artificial limbs. By deploying the wearable sensors inside the socket, the interfacial pressure distribution can be studied to find the active regions and rectify the socket design. In this case study, a clustering-based analysis method is presented to evaluate the density and layout of these sensors, which aims to reduce the local redundancy of the sensor deployment. In particular, a Self-Organizing Map (SOM) and K-means algorithm are employed to find the clustering results of the sensor data, taking the pressure measurement of a predefined sensor placement as the input. Then, one suitable clustering result is selected to detect the layout redundancy from the input area. After that, the Pearson correlation coefficient (PCC) is used as a similarity metric to guide the removal of redundant sensors and generate a new sparser layout. The Jenson-Shannon Divergence (JSD) and the mean pressure are applied as posterior validation metrics that compare the pressure features before and after sensor removal. A case study of a clinical trial with two sensor strips is used to prove the utility of the clustering-based analysis method. The sensors on the posterior and medial regions are suggested to be reduced, and the main pressure features are kept. The proposed method can help sensor designers optimize sensor configurations for intra-socket measurements and thus assist the prosthetists in improving the socket fitting.
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Affiliation(s)
- Wenyao Zhu
- School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, 10044 Stockholm, Sweden; (W.Z.); (Y.C.)
| | - Yizhi Chen
- School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, 10044 Stockholm, Sweden; (W.Z.); (Y.C.)
| | - Siu-Teing Ko
- Research and Innovation, Össur, 110 Reykjavík, Iceland;
| | - Zhonghai Lu
- School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, 10044 Stockholm, Sweden; (W.Z.); (Y.C.)
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10
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Scoping review to evaluate existing measurement parameters and clinical outcomes of transtibial prosthetic alignment and socket fit. Prosthet Orthot Int 2022; 46:95-107. [PMID: 35412519 DOI: 10.1097/pxr.0000000000000061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 08/09/2021] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Fit and alignment are observable objectives of the prosthesis rendering process for individuals with lower limb amputation. Nevertheless, there is a dearth of validated measures to directly assess the quality of this clinical procedure. OBJECTIVES The objectives of this scoping review are to evaluate existing measurement parameters and clinical outcomes used in investigations of transtibial socket fit or prosthetic alignment and to identify gaps in the literature regarding tools for evaluation of prosthetic fitting. STUDY DESIGN Scoping literature review. METHODS A comprehensive search was conducted in the following databases: MEDLINE (through PubMed), Embase (through Elsevier), Scopus (through Elsevier), and Engineering Village (through Elsevier), resulting in 6107 studies to be screened. RESULTS Sixty-three studies were included in the review. When measuring fit, studies most frequently reported on patient-reported comfort (n = 22) and socket size compared with the residual limb volume (n = 9). Alignment was most frequently measured by the prosthetists' judgment and/or use of an alignment jig (n = 34). The measurement parameters used to determine alignment or fit varied greatly among the included studies. CONCLUSION This review demonstrated that most measures of socket fit rely on a patient's self-report and may vary with biopsychosocial factors unrelated to the socket fitting process. Meanwhile, alignment is determined mostly by the prosthetist's judgment, paired with objective measurements, such as alignment jigs and gait analysis. Efforts to standardize and validate measures of these parameters of prosthetic fitting are vital to improving clinical practice and reporting outcomes.
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11
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Weathersby EJ, Vamos AC, Larsen BG, McLean JB, Carter RV, Allyn KJ, Ballesteros D, Wang H, deGrasse NS, Friedly JL, Hafner BJ, Garbini JL, Ciol MA, Sanders JE. Performance of an auto-adjusting prosthetic socket during walking with intermittent socket release. J Rehabil Assist Technol Eng 2022; 9:20556683221093271. [PMID: 35558157 PMCID: PMC9087223 DOI: 10.1177/20556683221093271] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 03/24/2022] [Indexed: 01/09/2023] Open
Abstract
Introduction A challenge in the engineering of auto-adjusting prosthetic sockets is to
maintain stable operation of the control system while users change their
bodily position and activity. The purpose of this study was to test the
stability of a socket that automatically adjusted socket size to maintain
fit. Socket release during sitting was conducted between bouts of
walking. Methods Adjustable sockets with sensors that monitored distance between the liner and
socket were fabricated. Motor-driven panels and a microprocessor-based
control system adjusted socket size during walking to maintain a target
sensed distance. Limb fluid volume was recorded continuously. During eight
sit/walk cycles, the socket panels were released upon sitting and then
returned to position for walking, either the size at the end of the prior
bout or a size 1.0% larger in volume. Results In six transtibial prosthesis users, the control system maintained stable
operation and did not saturate (move to and remain at the end of the
actuator’s range) during 98% of the walking bouts. Limb fluid volume changes
generally matched the panel position changes executed by the control
system. Conclusions Stable operation of the control system suggests that the auto-adjusting
socket is ready for testing in users’ at-home settings.
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Affiliation(s)
- Ethan J Weathersby
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Andrew C Vamos
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Jake B McLean
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ryan V Carter
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Daniel Ballesteros
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Horace Wang
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | | | - Janna L Friedly
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Brian J Hafner
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Joseph L Garbini
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - Marcia A Ciol
- Department of Rehabilitation Medicine, University of Washington, Seattle, WA, USA
| | - Joan E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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12
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Investigation of Orthopedic Prosthesis Socket Management after Transfemoral Amputation by Expert Survey. PROSTHESIS 2021. [DOI: 10.3390/prosthesis3020015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prosthesis treatment requires the close interaction of different actors. In fitting prostheses to patients, special attention is given to the manufacturing of the socket. The continuous development of the technologies involved in the fitting and optimization of prostheses is shown in the literature. The assessment of orthopedic technicians and their influence in the process is thus far largely unexplored. Ten orthopedic technicians were interviewed about the socket fitting process after transfemoral amputation. The research goal was to clarify the socket treatment process with regards to the German context. The results showed that the orthopedic technicians focussing on the patient during the fitting process. This study underlines the importance of interaction and empathy. Volume fluctuations are decisive within the treatment process and are interactively influenced by various factors. Furthermore, the research emphasizes the need for appropriate assistive technologies and the potential for the further development of existing systems.
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13
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Seo JH, Lee HJ, Seo DW, Lee DK, Kwon OW, Kwak MK, Lee KH. A Prosthetic Socket with Active Volume Compensation for Amputated Lower Limb. SENSORS 2021; 21:s21020407. [PMID: 33435553 PMCID: PMC7827594 DOI: 10.3390/s21020407] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/05/2021] [Accepted: 01/05/2021] [Indexed: 12/03/2022]
Abstract
Typically, the actual volume of the residual limb changes over time. This causes the prosthesis to not fit, and then pain and skin disease. In this study, a prosthetic socket was developed to compensate for the volume change of the residual limb. Using an inflatable air bladder, the proposed socket monitors the pressure in the socket and keeps the pressure distribution uniform and constant while walking. The socket has three air bladders on anterior and posterior tibia areas, a latching type 3-way pneumatic valve and a portable control device. In the paper, the mechanical properties of the air bladder were investigated, and the electromagnetic analysis was performed to design the pneumatic valve. The controller is based on a hysteresis control algorithm with a closed loop, which keeps the pressure in the socket close to the initial set point over a long period of time. In experiments, the proposed prosthesis was tested through the gait simulator that can imitate a human’s gait cycle. The active volume compensation of the socket was successfully verified during repetitive gait cycle using the weight loads of 50, 70, and 90 kg and the residual limb model with a variety of volumes. It was confirmed that the pressure of the residual limb recovered to the initial state through the active control. The pressure inside the socket had a steady state error of less than 0.75% even if the volume of the residual limb was changed from −7% to +7%.
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Affiliation(s)
- Ji-Hyeon Seo
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea; (J.-H.S.); (H.-J.L.); (D.-K.L.); (O.-W.K.)
- School of Mechanical Engineering, College of Engineering, Kyungpook National University, Daegu 41566, Korea;
| | - Hyuk-Jin Lee
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea; (J.-H.S.); (H.-J.L.); (D.-K.L.); (O.-W.K.)
| | - Dong-Wook Seo
- Department of Radio Communication Engineering/Interdisciplinary Major of Maritime AI Convergence, Korea Maritime and Ocean University, Busan 49112, Korea;
| | - Dong-Kyu Lee
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea; (J.-H.S.); (H.-J.L.); (D.-K.L.); (O.-W.K.)
| | - Oh-Won Kwon
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea; (J.-H.S.); (H.-J.L.); (D.-K.L.); (O.-W.K.)
| | - Moon-Kyu Kwak
- School of Mechanical Engineering, College of Engineering, Kyungpook National University, Daegu 41566, Korea;
| | - Kang-Ho Lee
- Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Korea; (J.-H.S.); (H.-J.L.); (D.-K.L.); (O.-W.K.)
- Correspondence:
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14
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Carter RV, Larsen BG, McLean JB, Garbini JL, Sanders JE. Incorporating a Ferrous Polymer Target into Elastomeric Liners for Socket Fit Sensing in Prosthesis Users. SENSORS 2020; 20:s20195620. [PMID: 33019604 PMCID: PMC7582797 DOI: 10.3390/s20195620] [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: 08/03/2020] [Revised: 09/15/2020] [Accepted: 09/24/2020] [Indexed: 11/16/2022]
Abstract
Liner-to-socket distance measurement using inductive sensing may be an effective means to continuously monitor socket fit in people using trans-tibial prostheses. A practical limitation, however, is a means to incorporate a thin uniform-thickness layer of conductive or magnetically permeable target material into the wide range of prosthetic liner products that people with limb amputation commonly use. In this paper, a method is presented whereby a 0.50-mm thickness ferrous polymer made from a SEEPS polymer and iron powder that is formed adjacent to a 0.25-mm thick non-ferrous layer of SEEPS polymer is assembled between two sheets of elastic fabric material. Bench testing showed that the fabrication procedure achieved a root-mean-square error in the thickness of this construct of 58 μm, helping to create a consistent calibration result over the entire surface. The original fabric backing of an off-the-shelf prosthetic liner was removed and replaced with the developed construct. When worn in the shoe of an able-bodied participant for 7.5 h per day for 28 days, the sensor well maintained the shape of its calibration curve at the start of wear, but a distance offset (shifting of the y-intercept) was introduced that increased during the initial approximately 12 days of wear. When the distance offset was corrected, for the primary distance range of clinical interest for this application (0.00–5.00 mm), the sensor maintained its calibration within 4.4%. Before being used in clinical application for liner-to-socket distance monitoring, new ferrous liners may need to be pre-worn so as to achieve a consistent distance reference.
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