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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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Tang J, Jiang L, McGrath M, Bader D, Laszczak P, Moser D, Zahedi S. Analysis of lower limb prosthetic socket interface based on stress and motion measurements. Proc Inst Mech Eng H 2022; 236:1349-1356. [PMID: 35821656 PMCID: PMC9449444 DOI: 10.1177/09544119221110712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The study was designed to establish a biomechanical assessment platform for the
lower limb residuum/socket interface as a function of duration and speed of
movement. The approach exploits an interface sensor which measures
multi-directional stresses at the interface. The corresponding interface
coupling motion was assessed using a 3D motion capture system. A longitudinal
study, involving a trans-femoral amputee, was conducted with nine repeated level
walking sessions over a 12-month period. The effect of walking speed on
interface biomechanics was also assessed. Interface peak pressures and shear
stresses in the range of 55–59 kPa and 12–19 kPa were measured, respectively,
over all sessions in the 12 months study period at the posterior-proximal
location of the residuum. The peak pressure and longitudinal shear values were
found to fluctuate approximately 11% and 40% as against its maximum value,
respectively, over 12 months. In addition, up to 12° of angular coupling and up
to 28 mm of pistoning were recorded over a gait cycle, which was found to change
by 29% and 45% respectively over the study period. The variation in walking
speed, by altering self-selected cadence, resulted in changes of pressure and
shear stresses at mid-stance of the gait cycle. In particular, as compared with
self-selected cadence, for fast speed, peak pressure and peak longitudinal shear
stress decreased by 5% and 33%, respectively. For slow speed, peak pressure and
peak longitudinal shear stress increased by 7% and 17%, respectively. The
corresponding angular and pistoning revealed a variation of up to 29% and 45%,
respectively. This biomechanical assessment approach shows promise in the
quantitative assessment of interface kinematics and kinetics for lower limb
prosthetics, the usage of which could assist the clinical assessment of
prosthetic socket fit.
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Affiliation(s)
- Jinghua Tang
- School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Liudi Jiang
- School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Michael McGrath
- School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
- Blatchford Products Ltd., Basingstoke, UK
| | - Dan Bader
- Skin Health Research Group, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, UK
| | - Piotr Laszczak
- School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - David Moser
- School of Engineering, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
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Design of adjustable frame-type prosthetic socket for lower limb. Ing Rech Biomed 2022. [DOI: 10.1016/j.irbm.2022.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Nia A, Toetschinger G, Kubinec T, Domayer S. Evaluation of the new, patient-adjustable socket system Varos in the early phase of prosthetic rehabilitation: a pilot study. Eur J Phys Rehabil Med 2022; 58:462-469. [PMID: 35148042 PMCID: PMC9980548 DOI: 10.23736/s1973-9087.22.07020-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Current prosthetic sockets often provide limited anatomical fit, especially in patients with residual limb volume changes and fluctuations. AIM To address these issues, Ottobock has developed the Varos Socket, a modular socket that can be adjusted by the user. The aim of this study was to evaluate the potential benefits and acceptance of a newly designed patient-adjustable socket in transfemoral amputees in early phase of prosthetic rehabilitation. DESIGN A prospective A-B-A pilot study was conducted. SETTING The setting of the study was an Orthopedic Rehabilitation Clinic. POPULATION Ten patients with unilateral transfemoral amputation and recent amputation. METHODS All patients underwent a standard rehabilitation program with physical therapy. The outcome measures included the Comprehensive Lower-limb Amputee Socket Survey (CLASS), Score Comfort Scale (SCS), a Socket Fit Scale, frequency of falls and stumbles, perceived pain, and satisfaction. RESULTS The total CLASS score and three sub-scores (i.e., stability, suspension, comfort) were significantly higher with Varos socket. Significantly improved comfort and quality of socket fit were observed as measured by the Socket-Comfort-Scale and Socket-Fit-Scale and a trend towards reduced residual limb pain. 87.5% of the patients reported higher satisfaction than with the standard socket. CONCLUSIONS The results suggest that the Varos socket improved comfort, stability, suspension, appearance, pain, and satisfaction in transfemoral amputees during the early rehabilitation program. A larger study and a longer observation period are warranted to confirm the results of this study. CLINICAL REHABILITATION IMPACT Quick and easy socket fitting as well as instant adjustability by the patient bear substantial potential to improve and accelerate the rehabilitation process in the early phase after amputation.
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Affiliation(s)
- Arastoo Nia
- Department of Orthopedics and Traumatology, Medical University of Vienna, General Hospital of Vienna, Vienna, Austria
| | | | - Tomas Kubinec
- Zicksee Orthopedic Rehabilitation Center, St. Andrä am Zicksee, Austria
| | - Stephan Domayer
- Zicksee Orthopedic Rehabilitation Center, St. Andrä am Zicksee, Austria -
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Raschke SU. Limb Prostheses: Industry 1.0 to 4.0: Perspectives on Technological Advances in Prosthetic Care. FRONTIERS IN REHABILITATION SCIENCES 2022; 3:854404. [PMID: 36188935 PMCID: PMC9397934 DOI: 10.3389/fresc.2022.854404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/10/2022] [Indexed: 11/13/2022]
Abstract
Technological advances from Industry 1.0 to 4.0, have exercised an increasing influence on prosthetic technology and practices. This paper explores the historical development of the sector within the greater context of industrial revolution. Over the course of the first and up the midpoint of the second industrial revolutions, Industry 1.0 and 2.0, the production and provision of prosthetic devices was an ad hoc process performed by a range of craftspeople. Historical events and technological innovation in the mid-part of Industry 2.0 created an inflection point resulting in the emergence of prosthetists who concentrated solely on hand crafting and fitting artificial limbs as a professional specialty. The third industrial revolution, Industry 3.0, began transforming prosthetic devices themselves. Static or body powered devices began to incorporate digital technology and myoelectric control options and hand carved wood sockets transitioned to laminated designs. Industry 4.0 continued digital advancements and augmenting them with data bases which to which machine learning (M/L) could be applied. This made it possible to use modeling software to better design various elements of prosthetic componentry in conjunction with new materials, additive manufacturing processes and mass customization capabilities. Digitization also began supporting clinical practices, allowing the development of clinical evaluation tools which were becoming a necessity as those paying for devices began requiring objective evidence that the prosthetic technology being paid for was clinically and functionally appropriate and cost effective. Two additional disruptive dynamics emerged. The first was the use of social media tools, allowing amputees to connect directly with engineers and tech developers and become participants in the prosthetic design process. The second was innovation in medical treatments, from diabetes treatments having the potential to reduce the number of lower limb amputations to Osseointegration techniques, which allow for the direct attachment of a prosthesis to a bone anchored implant. Both have the potential to impact prosthetic clinical and business models. Questions remains as to how current prosthetic clinical practitioners will respond and adapt as Industry 4.0 as it continues to shape the sector.
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Affiliation(s)
- Silvia Ursula Raschke
- British Columbia Institute of Technology, Applied Research, MAKE+, Burnaby, BC, Canada
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Abstract
INTRODUCTION The prosthetic socket is the connecting part between the stump and the prosthesis, which is the important basis for the function of the prosthesis. The current prosthetic socket is difficult in meeting the needs of amputees current, which is the main reason for amputees abandoning their prostheses. This paper reviews the design and use of prosthetic sockets for lower limb. AREAS COVERED The contribution of this publication is to review the skin problem, interface stress and volume fluctuations for prosthetic sockets, which are proposed as the key factors affecting the use of prosthetic sockets. Moreover, the lower limb prosthetic sockets are classified into the full-contact and the frame-type sockets according to the different contact type between stump and prosthetic socket, and their advantages and disadvantages are analyzed from different perspectives. EXPERT OPINION Aim to design the prosthetic socket with function transfer, suspension stability and comfort of socket, a design concept for prosthetic socket with self-adapt in real-time is proposed. It can be achieved by the smart materials with special mechanical properties.
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Affiliation(s)
- Minghui Wang
- Institute of Rehabilitation Engineering and Technology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China.,Shanghai Engineering Research Center of Assistive Devices, Shanghai, China
| | - Qingjun Nong
- Institute of Rehabilitation Engineering and Technology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China.,Shanghai Engineering Research Center of Assistive Devices, Shanghai, China
| | - Yunlong Liu
- Institute of Rehabilitation Engineering and Technology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China.,Shanghai Engineering Research Center of Assistive Devices, Shanghai, China
| | - Hongliu Yu
- Institute of Rehabilitation Engineering and Technology, School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China.,Shanghai Engineering Research Center of Assistive Devices, Shanghai, China
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Frossard L. A Preliminary Cost-Utility Analysis of the Prosthetic Care Innovations: Basic Framework. CANADIAN PROSTHETICS & ORTHOTICS JOURNAL 2021; 4:36365. [PMID: 37614995 PMCID: PMC10443481 DOI: 10.33137/cpoj.v4i2.36365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A preliminary cost-utility analysis (CUA) of prosthetic care innovations can provide timely information during the early stage of product development and clinical usage. Concepts of preliminary CUAs are emerging. However, several obstacles must be overcome before these analyses are performed routinely. Disparities of methods and high uncertainty make the outcomes of usual preliminary CUAs challenging to interpret, appraise and share. These shortcomings create opportunities for a basic framework of preliminary CUAs. First, I introduced a basic framework of a preliminary CUA built around a series of constructs and hands-on recommendations. Then, I appraised this framework considering the strengths and weaknesses, barriers and facilitators, and return on investment. The design of the basic framework was determined through the review of health economic and prosthetic-specific literature. A preliminary CUA comparing the costs and utilities between usual intervention and an innovation could be achieved through a 15-step iterative process focusing on feasibility, constructs, analysis, and interpretation of outcomes. This CUA provides sufficient evidence to identify knowledge gaps and improvement areas, educate about the design of subsequent full CUAs, and obtain fast-track approval from governing bodies. Like previous CUAs, the main limitations were inherent to the constructs (e.g., narrow perspective, plausible scenarios, mid-term time horizon, substantial assumptions, data mismatch, high uncertainty). Key facilitators potentially transferable across preliminary CUAs of prosthetic care innovations included choosing abided constructs, capitalizing on prior schedules of expenses, and benchmarking baseline or incremental utilities. This new approach with preliminary CUA can simplify the selection of methods, standardize outcomes, ease comparisons between innovations, and streamline pathways for adoption. Further collegial efforts toward validating standard preliminary CUAs will facilitate access to economic prosthetic care innovations, improving the lives of individuals suffering from limb loss worldwide.
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Affiliation(s)
- L Frossard
- YourResearchProject Pty Ltd, Brisbane, Australia
- Griffith University, Gold Coast, Australia
- University of the Sunshine Coast, Maroochydore, Australia
- Queensland University of Technology, Brisbane, Australia
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Frossard L. Trends and Opportunities in Health Economic Evaluations of Prosthetic Care Innovations. CANADIAN PROSTHETICS & ORTHOTICS JOURNAL 2021; 4:36364. [PMID: 37615000 PMCID: PMC10443521 DOI: 10.33137/cpoj.v4i2.36364] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Overcoming obstacles to prosthetic fittings requires frequent tryouts of sockets and components. Repetitions of interventions are upsetting for users and place substantial economic burden on healthcare systems. Encouraging prosthetic care innovations capable of alleviating clinical and financial shortcomings of socket-based solutions is essential. Nonetheless, evidence of socio-economic benefits of an innovation are required to facilitate access to markets. Unfortunately, complex decisions must be made when allocating resources toward the most relevant health economic evaluation (HEE) at a given stage of development of an innovation. This paper first, aimed to show the importance and challenges of HEEs of intervention facilitating prosthetic fittings. Next, the main trends in HEEs at various phases of product development and clinical acceptance of prosthetic care innovations were outlined. Then, opportunities for a basic framework of a preliminary cost-utility analysis (CUA) during the mid-stage of development of prosthetic care innovations were highlighted. To do this, fundamental and applied health economic literature and prosthetic-specific publications were reviewed to extract and analyse the trends in HEEs of new medical and prosthetic technologies, respectively. The findings show there is consensus around the weaknesses of full CUAs (e.g., lack of timeliness, resource-intensive) and strengths of preliminary CUAs (e.g., identify evidence gaps, educate design of full CUA, fast-track approval). However, several obstacles must be overcome before preliminary CUA of prosthetic care innovations will be routinely carried out. Disparities of methods and constructs of usual preliminary CUA are barriers that could be alleviated by a more standardized framework. The paper concludes by identifying that there are opportunities for the development of a basic framework of preliminary CUA of prosthetic care innovations. Ultimately, the collaborative design of a framework could simplify selection of the methods, standardise outcomes, ease comparisons between innovations and streamline pathways for adoption. This might facilitate access to economical solutions that could improve the life of individuals suffering from limb loss.
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Affiliation(s)
- L Frossard
- YourResearchProject Pty Ltd, Brisbane, Australia
- Griffith University, Gold Coast, Australia
- University of the Sunshine Coast, Maroochydore, Australia
- Queensland University of Technology, Brisbane, Australia
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Klenow TD, Schulz J. Adjustable-Volume Prosthetic Sockets: Market Overview and Value Propositions. CANADIAN PROSTHETICS & ORTHOTICS JOURNAL 2021; 4:35208. [PMID: 37615005 PMCID: PMC10443512 DOI: 10.33137/cpoj.v4i2.35208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The prosthetic socket is commonly considered to be the most important part of the prosthesis and lack of fit can lead to skin breakdown, reduction in wear, reduction in activity, and consequential deleterious health effects. Furthermore, approximately 90% of amputations are due to a vascular etiology, which affect fluid retention regularity, and even small limb volume fluctuations can lead to lack of fit. Adjustability in the socket volume has been suggested as a potential solution to common fit issues but has lacked market penetration mostly due to lack of reimbursement. Despite this there are several adjustable-volume sockets emerging on the market today including prefabricated, modular, custom with adjustable-volume component, custom with adjustable-volume feature, and adjustable-hybrid sockets. Prefabricated sockets are mass produced in common sizes and fit directly to the patient by a prosthetist using pad kits, BOA dials, or straps. Modular sockets are assembled to a patient or model with panels or struts attached to an adjustable base. Custom sockets with adjustable-volume elements are traditionally-fabricated sockets made to a model of a patient's limb with a volume-adjustable component added or volume-adjustable feature built in. Custom-hybrid sockets are made custom to a model of the patient's limb and incorporate several aspects of the previous socket types and include some radically-unique design aspects which cannot be limited to one category. These adjustable-volume sockets offer several advantages to traditional rigid-volume sockets for the patient, prosthetist, and providing clinic. The micro-adjustability for the patient allows them to alter fit without removing the socket, maintaining a more intimate fit throughout the day than traditional sockets. The macro-adjustability for the prosthetist allows for increased options for fit customization including the ability to reverse or undo changes without necessarily re-making the socket. This allows for the most optimal fit for the patient. Adjustable volume also present efficiencies in the fitting process by simplifying or eliminating steps including residual limb shape capture, form modification, diagnostic fabrication, iterative alteration, and definitive fabrication with the different socket types affecting different steps. Due to these factors, adjustable-volume sockets have disrupted the market to the point where reimbursement reform is needed including additional L-codes in the United States and fee-for-service or fee-for-outcome associated with prosthetic follow-up care. Prosthetic care should also be separated from durable medical equipment to allow for alternative reimbursement models. As reimbursement adapts prosthetists must adapt correspondingly to differentiate their skillset from other allied health providers including incorporating more objective methods to show superior care outcomes. This adaptation should include a continued push for state and municipal licensure of prosthetists.
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Affiliation(s)
- TD Klenow
- Martin Bionics Clinical Care, Fort Myers, Florida, USA
| | - J. Schulz
- Martin Bionics Innovations, Oklahoma City, Oklahoma, USA
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Fatone S, Caldwell R, Angelico J, Stine R, Kim KY, Gard S, Oros M. Comparison of Ischial Containment and Subischial Sockets on Comfort, Function, Quality of Life, and Satisfaction With Device in Persons With Unilateral Transfemoral Amputation: A Randomized Crossover Trial. Arch Phys Med Rehabil 2021; 102:2063-2073.e2. [PMID: 34214499 DOI: 10.1016/j.apmr.2021.05.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 05/20/2021] [Accepted: 05/27/2021] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To compare comfort and functional performance of the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket with the ischial containment (IC) socket in persons with unilateral transfemoral amputation. DESIGN Randomized crossover trial with two 7-week periods. SETTING Private prosthetic clinics and university research laboratory. PARTICIPANTS A total of 30 enrolled (N=30); 25 participants completed the study with full (n=18) or partial data (n=7). INTERVENTIONS Two custom-fabricated sockets (IC and NU-FlexSIV), worn full-time for 7 weeks, with testing at 1, 4, and 7 weeks after socket delivery. MAIN OUTCOME MEASURES The primary outcome was change in Socket Comfort Score (SCS) at 7 weeks. Secondary outcomes at 7 weeks included the Orthotic and Prosthetic Users' Survey (OPUS) to assess lower extremity functional status, health-related quality of life, and satisfaction with device, as well as the 5-Times Rapid Sit-to-Stand Test, Four Square Step Test, and T-Test of Agility to assess functional performance. RESULTS At 7 weeks, the mean SCS for IC (7.0±1.7) and NU-FlexSIV (8.4±1.1) Sockets were significantly different (P<.001; 95% confidence interval, 0.8-2.3). Results from a linear mixed-effects model, accounting for data from all time points, indicated that the SCS was 1.7 (SE=0.45) points higher for the NU-FlexSIV Socket (P<.001). For the secondary outcomes, only OPUS satisfaction with device was significantly better in the NU-FlexSIV Socket after accounting for all data points. CONCLUSIONS The results suggest that after 7 weeks' accommodation, the NU-FlexSIV Socket was more comfortable and led to greater satisfaction with device than the IC socket in persons with unilateral transfemoral amputation and K3/K4 mobility. Other patient-reported outcomes and function were no different between sockets.
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Affiliation(s)
- Stefania Fatone
- Department of Physical Medicine and Rehabilitation, Northwestern University, Feinberg School of Medicine, Chicago, IL.
| | - Ryan Caldwell
- Department of Physical Medicine and Rehabilitation, Northwestern University, Feinberg School of Medicine, Chicago, IL; Scheck and Siress Prosthetics and Orthotics, Chicago, IL; Hanger Clinic, Austin, TX
| | - John Angelico
- Scheck and Siress Prosthetics and Orthotics, Chicago, IL; Hanger Clinic, Austin, TX
| | | | - Kwang-Youn Kim
- Department of Preventive Medicine, Northwestern University, Feinberg School of Medicine, Chicago, IL
| | - Steven Gard
- Department of Physical Medicine and Rehabilitation, Northwestern University, Feinberg School of Medicine, Chicago, IL; Jesse Brown VA Medical Center, Chicago, IL
| | - Michael Oros
- Scheck and Siress Prosthetics and Orthotics, Chicago, IL; Hanger Clinic, Austin, TX
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Yazgan A, Kutlutürk S, Lechler K. Clinical Outcomes Comparing Two Prosthetic Knee Designs in Individuals with Unilateral Transfemoral Amputation in Turkey. CANADIAN PROSTHETICS & ORTHOTICS JOURNAL 2021; 4:35297. [PMID: 37614931 PMCID: PMC10443503 DOI: 10.33137/cpoj.v4i1.35297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 06/22/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Clinical outcome assessments provide important input for the rehabilitation of individuals with transfemoral amputation. Differences in prosthetic knee designs may influence clinical outcomes. OBJECTIVES The aim of this study was to compare functional mobility, balance, prosthetic satisfaction and quality of life in individuals with unilateral transfemoral amputation with microprocessor-controlled (MPK) and non-microprocessor knee designs (Non-MPK). METHODOLOGY The study included ten experienced MPK (Rheo Knee) users (Group 1) and ten experienced Non-MPK (Total Knee® 2000) users (Group 2). For mobility; the 6 Minute Walk Test (6MWT), for balance; the Berg Balance Scale (BBS), Single Leg Stand Test (SLST) and Four Square Step Test (FSST), for quality of life; the Nottingham Health Profile (NHP) and for prosthetic satisfaction; the Satisfaction with Prosthesis Questionnaire (SATPRO) were administered. FINDINGS 6MWT results of the MPK group were significantly higher than Non-MPK group (p<0.05). In the MPK group a strong negative correlation was found between the FSST and the 6MWT (r=-0.661, p=0.038). No statistically significant differences were found between the groups (p>0.05) comparing balance, prosthesis satisfaction and quality of life values. CONCLUSION The findings will inform about the patient's prognosis and the expected clinical outcomes when prescribing an MPK or an Non-MPK. Individuals with unilateral transfemoral amputation covered longer distances using an MPK compared to Non-MPK.
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Affiliation(s)
- A Yazgan
- Orthotics - Prosthetics Master of Science Program, Graduate School of Healthy Sciences, Istanbul Medipol University, Istanbul, Turkey
- Össur Turkey Academy, Istanbul, Turkey
| | - S Kutlutürk
- Department of Physical Therapy and Rehabilitation, School of Healthy Sciences, Istanbul Medipol University, Istanbul, Turkey
| | - K Lechler
- Össur Medical Office, R&D Össur ehf, Reykjavik, Iceland
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Paternò L, Ibrahimi M, Rosini E, Menfi G, Monaco V, Gruppioni E, Ricotti L, Menciassi A. Residual limb volume fluctuations in transfemoral amputees. Sci Rep 2021; 11:12273. [PMID: 34112873 PMCID: PMC8192500 DOI: 10.1038/s41598-021-91647-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/31/2021] [Indexed: 11/08/2022] Open
Abstract
This study constitutes the first attempt to systematically quantify residual limb volume fluctuations in transfemoral amputees. The study was carried out on 24 amputees to investigate variations due to prosthesis doffing, physical activity, and testing time. A proper experimental set-up was designed, including a 3D optical scanner to improve precision and acceptability by amputees. The first test session aimed at measuring residual limb volume at 7 time-points, with 10 min intervals, after prosthesis doffing. This allowed for evaluating the time required for volume stabilization after prosthesis removal, for each amputee. In subsequent sessions, 16 residual limb scans in a day for each amputee were captured to evaluate volume fluctuations due to prosthesis removal and physical activity, in two times per day (morning and afternoon). These measurements were repeated in three different days, a week apart from each other, for a total of 48 scans for each amputee. Volume fluctuations over time after prosthesis doffing showed a two-term decay exponential trend (R2 = 0.97), with the highest variation in the initial 10 min and an average stabilization time of 30 min. A statistically significant increase in residual limb volume following both prosthesis removal and physical activity was verified. No differences were observed between measures collected in the morning and in the afternoon.Clinical Trials.gov ID: NCT04709367.
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Affiliation(s)
- Linda Paternò
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy.
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy.
| | - Michele Ibrahimi
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Elisa Rosini
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Giuseppe Menfi
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Vito Monaco
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
- IRCCS Fondazione Don Carlo Gnocchi, 20148, Milan, Italy
| | | | - Leonardo Ricotti
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Arianna Menciassi
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics & AI, Scuola Superiore Sant'Anna, Pisa, Italy
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14
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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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Weathersby EJ, Garbini JL, Larsen BG, McLean JB, Vamos AC, Sanders JE. Automatic Control of Prosthetic Socket Size for People WithTranstibial Amputation: Implementation and Evaluation. IEEE Trans Biomed Eng 2020; 68:36-46. [PMID: 32386137 DOI: 10.1109/tbme.2020.2992739] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE The purpose was to design, implement, and test a control system for a motor-actuated, cable-panel prosthetic socket that automatically maintains socket fit by continuous adjustment of the socket size. METHODS Sockets with motor-driven adjustable panels were fabricated for participants with transtibial amputation. A proportional-integral control system was implemented to adjust socket size based on Socket Fit Metric (SFM) data collected by an inductive sensor embedded within the socket wall. The sensed distance was representative of limb-to-socket distance. Testing was conducted with participants walking on a treadmill to characterize the system's capability to maintain a set point and to respond to a change in the set point. RESULTS Test results from 10 participants with transtibial amputation showed that the Integral of Absolute Error (IAE) to maintain a set point ranged from 0.001 to 0.046 mm with a median of 0.003 mm. When the set point was changed, IAE errors ranged from 0.001 to 0.005 mm, with a median of 0.003 mm. An IAE of 0.003 mm corresponded to approximately a 0.08% socket volume error, which was considered clinically acceptable. CONCLUSION The capability of the control system to maintain and respond to a change in set point indicates that it is ready for evaluation outside of the laboratory. SIGNIFICANCE Integration of the developed control system into everyday prostheses may improve quality of life of prosthesis users by relieving them of the burden of continually adjusting socket size to maintain fit.
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16
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Kahle J, Miro RM, Ho LT, Porter M, Lura DJ, Carey SL, Lunseth P, Highsmith J, Highsmith MJ. The effect of the transfemoral prosthetic socket interface designs on skeletal motion and socket comfort: A randomized clinical trial. Prosthet Orthot Int 2020; 44:145-154. [PMID: 32308126 DOI: 10.1177/0309364620913459] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND The most crucial aspect of a prosthesis is the socket, as it will directly determine gait stability and quality. The current standard of care ischial ramus containment socket is reported to increase coronal stability through gait; however, socket discomfort is the primary complaint among prosthetic users. OBJECTIVES The purpose of this study is to compare ischial ramus containment to alternatives in the transfemoral amputee population. All subjects were fit with three different sockets: traditional ischial ramus containment, a dynamic socket, and a sub-ischial. In this study, authors hypothesized socket skeletal motion would be equivalent across interventions. STUDY DESIGN Single-blind, repeated-measures, three-period randomized crossover clinical trial. METHODS Outcome measures were socket comfort score and skeletal motion, viewed coronally with X-ray measuring the position of the skeleton in relationship to the socket in full weight-bearing and full un-loading. RESULTS The mean age was 38.2 and mean Amputee Mobility Predictor score was 40. Mean vertical movement, horizontal movement, single limb prosthetic stance, mean femoral adduction in swing and stance, and median socket comfort score were not statistically different. CONCLUSION The socket design did not significantly effect skeletal motion and socket comfort. All socket designs are suitable depending on the patient-centric preferences and prosthetist skill set. CLINICAL RELEVANCE The comfort of the standard of care transfemoral amputation socket has been widely reported as problematic. A comparison of alternative designs in a controlled clinical trial environment will assist the clinician in understanding the impact of design regarding skeletal motion and comfort. Users could benefit from alternatives applied in clinical practice.
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Affiliation(s)
| | | | - Loi T Ho
- Prosthetic Design + Research, Tampa, FL, USA
| | | | - Derek J Lura
- Florida Gulf Coast University, Fort Myers, FL, USA
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17
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McLean JB, Larsen BG, Weathersby EJ, Carter Bs RV, Allyn KJ, Garbini JL, Sanders JE. Fluid Volume Management in Prosthesis Users: Augmenting Panel Release with Pin Release. PM R 2020; 12:1236-1243. [PMID: 32103634 DOI: 10.1002/pmrj.12349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 02/03/2020] [Accepted: 02/12/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Management of fluid in the limbs is a challenge faced by people with disabilities. In prosthetics, a means for transtibial prosthesis users to stabilize their residual limb fluid volume during the day may improve socket fit. OBJECTIVE To determine if releasing the panels and locking pin of a cabled-panel adjustable socket during socket release significantly improved limb fluid volume recovery and retention over releasing the panels alone. DESIGN Repeated-measures experiment to assess the effects on limb fluid volume retention. SETTING Participants were tested in a laboratory setting while walking on a treadmill. INTERVENTION Release of a locking pin tether during sitting as a limb volume accommodation strategy. MAIN OUTCOME MEASURE Percent limb fluid volume retention for panel and pin release compared with panel release alone at 2 minutes (short term) and 50 minutes (long term) after subsequent activity. Limb fluid volume was monitored using bioimpedance analysis. RESULTS Median percent limb fluid volume retention for the panel and pin release was significantly greater than panel release alone for both anterior and posterior regions for the long term (P = .0499 and .0096, respectively) but not the short term (P = .0712 and .1580, respectively). CONCLUSION Augmenting panel release with pin release may be an effective accommodation strategy for prosthesis users with transtibial amputation to better retain limb fluid volume.
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Affiliation(s)
- Jake B McLean
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ethan J Weathersby
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Ryan V Carter Bs
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Joseph L Garbini
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Joan E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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18
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Mbithi FM, Chipperfield AJ, Steer JW, Dickinson AS. Predictive Control for an Active Prosthetic Socket informed by FEA-based Tissue Damage Risk Estimation. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2019:2073-2076. [PMID: 31946309 DOI: 10.1109/embc.2019.8857155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This paper presents an architecture for generalized predictive control for an active prosthetic socket system, based on a cost function performance index measure for minimization of residual limb tissue injury. Finite element analysis of a transtibial residuum model donned with a total surface bearing socket was used to provide controller training data and biomechanical rationale for deep tissue injury risk assessment, by estimating the internal deformation state of the soft tissues and the residuum-socket interface loading under a range of prosthetic loading instances. The results demonstrate the concept of this approach for interface actuation modelled as translational spring and damper systems.
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19
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Gupta S, Loh KJ, Pedtke A. Sensing and actuation technologies for smart socket prostheses. Biomed Eng Lett 2019; 10:103-118. [PMID: 32175132 DOI: 10.1007/s13534-019-00137-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/17/2019] [Accepted: 10/26/2019] [Indexed: 01/20/2023] Open
Abstract
The socket is the most critical part of every lower-limb prosthetic system, since it serves as the interfacial component that connects the residual limb with the artificial system. However, many amputees abandon their socket prostheses due to the high-level of discomfort caused by the poor interaction between the socket and residual limb. In general, socket prosthesis performance is determined by three main factors, namely, residual limb-socket interfacial stress, volume fluctuation of the residual limb, and temperature. This review paper summarizes the various sensing and actuation solutions that have been proposed for improving socket performance and for realizing next-generation socket prostheses. The working principles of different sensors and how they have been tested or used for monitoring the socket interface are discussed. Furthermore, various actuation methods that have been proposed for actively modifying and improving the socket interface are also reviewed. Through the continued development and integration of these sensing and actuation technologies, the long-term vision is to realize smart socket prostheses. Such smart socket systems will not only function as a socket prosthesis but will also be able to sense parameters that cause amputee discomfort and self-adjust to optimize its fit, function, and performance.
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Affiliation(s)
- Sumit Gupta
- 1Department of Structural Engineering, University of California-San Diego, La Jolla, CA 92093-0085 USA
| | - Kenneth J Loh
- 1Department of Structural Engineering, University of California-San Diego, La Jolla, CA 92093-0085 USA
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20
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Larsen BG, McLean JB, Allyn KJ, Brzostowski JT, Garbini JL, Sanders JE. How do transtibial residual limbs adjust to intermittent incremental socket volume changes? Prosthet Orthot Int 2019; 43:528-539. [PMID: 31339448 DOI: 10.1177/0309364619864771] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Strategies to maintain prosthesis users' daily limb volume are needed. OBJECTIVES Test how intermittent incremental socket volume adjustments affect limb fluid volume and limb-socket distance. STUDY DESIGN Repeated measures. METHODS People with transtibial limb loss walked on an outdoor trail wearing a motor-driven adjustable socket that they adjusted a small amount, approximately 0.3% socket volume, every 2 min using a mobile phone app. Limb fluid volume and sensed distance between the socket and a target in their elastomeric liner were monitored. A gradual socket enlargement phase was followed by a gradual socket reduction phase. RESULTS An incremental socket enlargement significantly increased limb fluid volume (p < 0.001) but not sensed distance (p = 0.063). An incremental socket reduction significantly decreased both limb fluid volume (p < 0.001) and sensed distance (p < 0.001). CONCLUSION Participants' residual limb fluid volume increases during ambulation compensated for incremental socket volume increases. For incremental socket volume decreases, residual limb fluid volume decreases did not compensate and the socket fit became tighter. CLINICAL RELEVANCE Results support the hypothesis that for people without co-morbidities, intermittent incremental socket volume enlargements are an effective accommodation strategy to increase limb fluid volume while maintaining socket fit. Intermittent incremental socket volume reductions decreased limb fluid volume but also made the socket fit tighter.
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Affiliation(s)
- Brian G Larsen
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Jake B McLean
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Katheryn J Allyn
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | | | - Joseph L Garbini
- Department of Mechanical Engineering, University of Washington, Seattle, WA, USA
| | - Joan E Sanders
- Department of Bioengineering, University of Washington, Seattle, WA, USA
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21
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Weathersby EJ, Gurrey CJ, McLean JB, Sanders BN, Larsen BG, Carter R, Garbini JL, Sanders JE. Thin Magnetically Permeable Targets for Inductive Sensing: Application to Limb Prosthetics. SENSORS (BASEL, SWITZERLAND) 2019; 19:E4041. [PMID: 31546816 PMCID: PMC6767675 DOI: 10.3390/s19184041] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 09/04/2019] [Accepted: 09/12/2019] [Indexed: 11/16/2022]
Abstract
The purpose of this research was to create a thin ferrous polymer composite to be used as a target for inductive sensing in limb prosthetics. Inductive sensors are used to monitor limb-to-socket distance in prosthetic sockets, which reflects socket fit. A styrene-ethylene-ethylene/propylene-styrene (SEEPS) polymer was mixed with iron powder at three concentrations (75, 77, 85 wt%), and thin disk-shaped samples were fabricated (0.50, 0,75, 1.00 mm thickness). For 85 wt% samples of 0.50 mm thickness, which proved the best combination of high signal strength and low target volume, inductive sensor sensitivity ranged from 3.2E5 counts/mm at 0.00-1.00 mm distances to 7.2E4 counts/mm at 4.00-5.00 mm distances. The application of compressive stress (up to 425 kPa) introduced an absolute measurement error of less than 3.3 μm. Tensile elasticity was 282 kPa, which is comparable to that of commercial elastomeric liners. Durability testing in the shoe of an able-bodied participant demonstrated a change in calibration coefficient of less than 3.8% over two weeks of wear. The ferrous polymer composite may facilitate the development of automatically adjusting sockets that use limb-to-socket distance measurement for feedback control.
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Affiliation(s)
- Ethan J Weathersby
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Clement J Gurrey
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Jake B McLean
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Benjamin N Sanders
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Brian G Larsen
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Ryan Carter
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Joseph L Garbini
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
| | - Joan E Sanders
- Department of Bioengineering, University of Washington, 3720 15th Ave NE, Box 355061, Seattle, WA 98195-5061, USA.
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22
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McLean JB, Redd CB, Larsen BG, Garbini JL, Brzostowski JT, Hafner BJ, Sanders JE. Socket size adjustments in people with transtibial amputation: Effects on residual limb fluid volume and limb-socket distance. Clin Biomech (Bristol, Avon) 2019; 63:161-171. [PMID: 30901641 DOI: 10.1016/j.clinbiomech.2019.02.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 02/27/2019] [Accepted: 02/28/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Small intermittent adjustments of socket size using adjustable sockets may be a means for people with transtibial amputation to better maintain residual limb fluid volume and limb position while using a prosthesis. METHODS Socket size, limb fluid volume, and distance from the limb to the socket, termed "sensed distance," were recorded while participants with transtibial amputation walked on a treadmill wearing a motor-driven, cabled-panel, adjustable socket. Researchers made frequent socket size adjustments using a mobile phone app to identify participants' acceptable socket size range. Limb fluid volume and sensed distance were then monitored as incremental adjustments were made to the socket. FINDINGS Prosthesis users in this study (n = 10) accepted socket sizes between -5% and +5% of their neutral socket volume. There was a rapid increase in limb fluid volume and sensed distance upon socket enlargement, and a rapid decrease upon reduction. Subsequently, there were gradual changes in fluid volume and sensed distance. While visually monitoring limb fluid volume data in real time, researchers were able to adjust socket size to maintain consistent limb fluid volume within a -0.7% to +0.9% volume change for 24 min. INTERPRETATION Participant residual limbs compensated to socket size adjustment. Using socket-mounted sensors to monitor limb-socket mechanics, an automatic adjustable socket that maintains limb fluid volume may be possible and may improve socket fit in instances where fit deteriorates during use.
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Affiliation(s)
- Jake B McLean
- Department of Bioengineering, 355061, 3720 15th Ave NE, University of Washington, Seattle, WA 98105, USA
| | - Christian B Redd
- Department of Bioengineering, 355061, 3720 15th Ave NE, University of Washington, Seattle, WA 98105, USA
| | - Brian G Larsen
- Department of Bioengineering, 355061, 3720 15th Ave NE, University of Washington, Seattle, WA 98105, USA
| | - Joseph L Garbini
- Department of Mechanical Engineering, 352600, 3900 E Stevens Way NE, University of Washington, Seattle, WA 98105, USA
| | - Jacob T Brzostowski
- Department of Bioengineering, 355061, 3720 15th Ave NE, University of Washington, Seattle, WA 98105, USA
| | - Brian J Hafner
- Department of Rehabilitation Medicine, 356490, 1959 NE Pacific St, 8th floor North Wing, University of Washington, Seattle, WA 98195, USA
| | - Joan E Sanders
- Department of Bioengineering, 355061, 3720 15th Ave NE, University of Washington, Seattle, WA 98105, USA.
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23
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Rush MN, Hagin E, Nguyen J, Lujan V, Dutton RA, Salas C. Design for Transtibial Modifiable Socket for Immediate Postoperative Prosthesis. UNIVERSITY OF NEW MEXICO ORTHOPAEDICS RESEARCH JOURNAL 2019; 8:93-97. [PMID: 31903301 PMCID: PMC6941796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Amputations are long-standing surgical procedures that have been performed for centuries; however, very little attention and urgency have been given to immediate restoration of movement and return to a normal lifestyle. In many cases, the time between amputation and prosthetic fitting can pause recovery and development of new routines. To increase recovery, immediate postoperative prostheses (IPOPs) have been developed yet these are under-utilized because of concerns for wound healing and complications with vascular diseases. Subsequently, we designed a transtibial IPOP that utilizes an ergonomic modifiable socket that allows for examination, wound care, and in situ edema control. Additionally, the IPOP facilitates early weight bearing and protects the amputated limb from external trauma postoperatively. Our purpose is to introduce this technology and describe how its unique design will serve to provide potential benefits and positive effects on patients who have undergone amputations.
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Affiliation(s)
- Matthew N. Rush
- Nanoscience and Microsystems Engineering, The University of New Mexico, Albuquerque, New Mexico
- Center for Biomedical Engineering, The University of New Mexico, Albuquerque, New Mexico
- M. N. Rush, PhD. Department of Chemistry and Biochemistry, Northern Arizona University, Flagstaff, Arizona
| | - Evan Hagin
- Department of Mechanical Engineering, The University of New Mexico, Albuquerque, New Mexico
| | - Jane Nguyen
- Department of Chemical and Biological Engineering, The University of New Mexico, Albuquerque, New Mexico
- J. Nguyen, BS. Johns Hopkins University, Baltimore, Maryland
| | - Victoria Lujan
- Department of Chemical and Biological Engineering, The University of New Mexico, Albuquerque, New Mexico
| | - Rebecca A. Dutton
- Department of Orthopaedics & Rehabilitation, The University of New Mexico, Albuquerque, New Mexico
| | - Christina Salas
- Center for Biomedical Engineering, The University of New Mexico, Albuquerque, New Mexico
- Department of Mechanical Engineering, The University of New Mexico, Albuquerque, New Mexico
- Department of Orthopaedics & Rehabilitation, The University of New Mexico, Albuquerque, New Mexico
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24
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Paterno L, Ibrahimi M, Gruppioni E, Menciassi A, Ricotti L. Sockets for Limb Prostheses: A Review of Existing Technologies and Open Challenges. IEEE Trans Biomed Eng 2018; 65:1996-2010. [PMID: 29993506 DOI: 10.1109/tbme.2017.2775100] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In the prosthetics field, one of the most important bottlenecks is still the human-machine interface, namely the socket. Indeed, a large number of amputees still rejects prostheses or points out a low satisfaction level, due to a sub-optimal interaction between the socket and the residual limb tissues. The aim of this paper is to describe the main parameters (displacements, stress, volume fluctuations and temperature) affecting the stump-socket interface and reducing the comfort/stability of limb prostheses. In this review, a classification of the different socket types proposed in the literature is reported, together with an analysis of advantages and disadvantages of the different solutions, from multiple viewpoints. The paper then describes the technological solutions available to face an altered distribution of stresses on the residual limb tissues, volume fluctuations affecting the stump overtime and temperature variations affecting the residual tissues within the socket. The open challenges in this research field are highlighted and the possible future routes are discussed, towards the ambitious objective of achieving an advanced socket able to self-adapt in real-time to the complex interplay of factors affecting the stump, during both static and dynamic tasks.
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