The development and internal consistency of the comprehensive lower limb amputee socket survey in active lower limb amputees

"A good socket fit can make you or break you": A multimethod study to explore the perceptions and experiences of socket fitting among people with lower-limb loss in Australia

BACKGROUND

Iterative design and modification are used to manufacture lower limb prosthetic sockets that meet users' needs while also fulfilling safety and mobility criteria. Greater understanding of the expectations of prosthesis users regarding prosthetic fit as well as their experiences at the time of socket fitting is needed.

OBJECTIVES

Describe lower limb prosthesis user perceptions and experiences of socket comfort and discomfort during their last fitting and compare this to their expectations for a perfectly fitting socket and their satisfaction with the socket they had fitted.

STUDY DESIGN

Mixed methods (quantitative and qualitative).

METHODS

A questionnaire was designed and administered in consultation with Amputees NSW (an amputee advocacy group) and distributed through their membership database. Qualitative responses were analyzed to explore prosthesis user experiences of socket fitting, general wear, as well as socket comfort, discomfort, and satisfaction. Quantitative responses were analyzed using descriptive, nonparametric methods.

RESULTS

Thirty participants with a range of lived experiences completed the questionnaire. Reported comfort and discomfort varied across participants and indicated that expectations and experiences of fit varied and changed over time, with some participants anticipating adjustment over time would be necessary. Qualitative analysis found experiences of prosthesis socket comfort/discomfort on the day of fitting and general experiences of socket comfort related to 2 key factors-the prosthesis itself and the individual prosthesis user.

CONCLUSIONS

Understanding the experiences and expectations of prosthesis users for comfort and intended activities is central to ensure success of the socket fitting approach. Investigation into fit changes over time could provide insights into follow-up requirements, user education, and funding mechanisms.

Prosthesis and health-related factors of mobility in people with nontraumatic unilateral transtibial amputation

BACKGROUND

Numerous factors can affect mobility of individuals with lower limb amputation, including prosthesis-dependent, physical and psychological determinants.Objective:This study aimed to investigate the prosthesis and health-related factors of mobility in people with nontraumatic unilateral transtibial amputation.Study Design:Cross-sectional observational study.

METHODS

Individuals with nontraumatic unilateral transtibial amputation who are using a prosthetic leg were included. All participants were asked to fill out the Prosthesis Evaluation Questionnaire, 12-Item Short-Form Health Survey (SF-12), Comprehensive Lower Limb Amputee Socket Survey, and 12-item Prosthetic Limb Users Survey of Mobility. The relationships between the variables of interest and mobility were investigated using correlation coefficient analyses. Multiple regression analysis was run to investigate the impact of a set of predictor variables on mobility.

RESULTS

A total of 168 people with lower limb amputation were included. Mobility had a significant association with age, comorbidity, occupation, Prosthesis Evaluation Questionnaire score, physical and mental component scores of SF-12, subscales of the Comprehensive Lower Limb Amputee Socket Survey, educational status, amputation cause, time since amputation, time since using the prosthesis, and socket insert type. In the final model of multiple regression analysis, the Physical Component Summary score of SF-12 showed the strongest predictor of mobility (beta = 0.40, p < 0.001).

CONCLUSIONS

Nonprosthetic factors play a significant role in mobility of people with nontraumatic unilateral transtibial amputation. Although some predictors, such as age and time since amputation, are immutable, clinicians may still enhance the mobility of this population through the utilization of health-related factors, such as improving their physical activity.

The Overlay, a New Solution for Volume Variations in the Residual Limb for Individuals with a Transtibial Amputation

BACKGROUND

The company Ethnocare has developed the Overlay, a new pneumatic solution for managing volumetric variations (VVs) of the residual limb (RL) in transtibial amputees (TTAs), which improves socket fitting. However, the impact of the Overlay during functional tasks and on the comfort and pain felt in the RL is unknown.

METHODS

8 TTAs participated in two evaluations, separated by two weeks. We measured compensatory strategies (CS) using spatio-temporal parameters and three-dimensional lower limb kinematics and kinetics during gait and sit-to-stand (STS) tasks. During each visit, the participant carried out our protocol while wearing the Overlay and prosthetic folds (PFs), the most common solution to VV. Between each task, comfort and pain felt were assessed using visual analog scales.

RESULTS

While walking, the cadence with the Overlay was 105 steps/min, while it was 101 steps/min with PFs (p = 0.021). During 35% and 55% of the STS cycle, less hip flexion was observed while wearing the Overlay compared to PFs (p = 0.004). We found asymmetry coefficients of 13.9% with the Overlay and 17% with PFs during the STS (p = 0.016) task. Pain (p = 0.031), comfort (p = 0.017), and satisfaction (p = 0.041) were better with the Overlay during the second visit.

CONCLUSION

The Overlay's impact is similar to PFs' but provides less pain and better comfort.

Walking Exercise Sustainability Through Telehealth for Veterans With Lower-Limb Amputation: A Study Protocol

OBJECTIVE

This randomized controlled superiority trial will determine if an 18-month telehealth walking exercise self-management program produces clinically meaningful changes in walking exercise sustainability compared to attention-control education for veterans living with lower-limb amputation.

METHODS

Seventy-eight participants with lower-limb amputation (traumatic or nontraumatic) aged 50 to 89 years will be enrolled. Two groups will complete 6 one-on-one intervention sessions, and 6 group sessions over an 18-month intervention period. The experimental arm will receive a self-management program focusing on increasing walking exercise and the control group will receive attention-control education specific to healthy aging. Daily walking step count (primary outcome) will be continuously monitored using an accelerometer over the 18-month study period. Secondary outcomes are designed to assess potential translation of the walking exercise intervention into conventional amputation care across the Veteran Affairs Amputation System of Care. These secondary outcomes include measures of intervention reach, efficacy, likelihood of clinical adoption, potential for clinical implementation, and ability of participants to maintain long-term exercise behavior.

IMPACT

The unique rehabilitation paradigm used in this study addresses the problem of chronic sedentary lifestyles following lower-limb amputation through a telehealth home-based walking exercise self-management model. The approach includes 18 months of exercise support from clinicians and peers. Trial results will provide rehabilitation knowledge necessary for implementing clinical translation of self-management interventions to sustain walking exercise for veterans living with lower-limb amputation, resulting in a healthier lifestyle.

Evidencing the effectiveness of upper limb prostheses: a multi-stakeholder perspective on study requirements

The provision of upper limb prosthetic devices through the National Health Services (NHS) within the United Kingdom is driven by national policies. NHS England have recently published a new policy to provide multi-grip myoelectric hands. The policy highlighted that there was limited evidence to support its deployment and it will be reviewed should new information arise. The clear identification of the evidence gap provides an opportunity for the academic research community to conduct studies that will inform future iterations of this and other upper limb prosthetic related policies. This paper presents a summary of findings and recommendations based on two multi-stakeholder workshops held in June 2022 and July 2022, which explored the design requirements for policy-driven research studies. The workshops involved people from a broad range of stakeholder groups: policy, academia, NHS clinical and management, industry, and a person with upper limb absence. The workshop discussions focused on the research questions that NHS England identified in the policy evidence review: (1) Clinical Effectiveness; (2) Cost Effectiveness; (3) Safety; and (4) Patient Subgroups. The recommendations based on stakeholder discussions included the need to gather qualitative and quantitative research evidence, use goal-based outcome measures, and conduct longitudinal studies. Future research studies also need to address the complexities of conducting national and international policy-driven research, such as clinical resource capacity and participant involvement.

Exploring meaningful outcome domains of recovery following lower limb amputation and prosthetic rehabilitation: the patient's perspective

PURPOSE

There is currently no consensus regarding what outcome domains to measure following lower limb prosthetic rehabilitation. Prosthetic users have a unique insight into important outcome domains, little is currently known about their critical viewpoint.

MATERIALS AND METHODS

A total of 37 participants who underwent lower limb amputation in the last five years were recruited from UK limb fitting centres and social media. Data were collected using focus groups and interviews and analysed using reflexive thematic analysis.

RESULTS

Five themes were identified. 1) The ability to participate in important activities, 2) how participants were able to undertake these activities, i.e., independently, with ease, safely and with minimal equipment. 3) A comfortable, easy-to-use prosthesis, 4) the importance of managing pain and finally, 5) adjusting and accepting their new normal. These five themes, or outcome domains, did not exist in isolation, but appeared to interact with each other, contributing to, or inhibiting the participant's holistic sense of recovery.

CONCLUSIONS

Understanding important outcome domains that define what recovery means to people following amputation can help to inform domain consensus, as well as direct the focus of rehabilitation. Domain consensus would guide the selection of measurement tools that evaluate prosthetic interventions in a meaningful way.IMPLICATIONS FOR REHABILITATIONThere is currently no consensus around which outcome domains should be measured following prosthetic rehabilitation.Outcome domains of importance from a patient's perspective focus on participation in important activities, prosthesis comfort, pain management, and acceptance of their new normal.Identifying these domains can help direct the focus of rehabilitation as well as inform outcome measurement practice.The interrelated nature of these domains suggests the need for a physical and psychosocial multi-domain approach to outcome measurement in prosthetic rehabilitation, with patient priorities at its centre.

A Workflow for Studying the Stump-Socket Interface in Persons with Transtibial Amputation through 3D Thermographic Mapping

The design and fitting of prosthetic sockets can significantly affect the acceptance of an artificial limb by persons with lower limb amputations. Clinical fitting is typically an iterative process, which requires patients' feedback and professional assessment. When feedback is unreliable due to the patient's physical or psychological conditions, quantitative measures can support decision-making. Specifically, monitoring the skin temperature of the residual limb can provide valuable information regarding unwanted mechanical stresses and reduced vascularization, which can lead to inflammation, skin sores and ulcerations. Multiple 2D images to examine a real-life 3D limb can be cumbersome and might only offer a partial assessment of critical areas. To overcome these issues, we developed a workflow for integrating thermographic information on the 3D scan of a residual limb, with intrinsic reconstruction quality measures. Specifically, workflow allows us to calculate a 3D thermal map of the skin of the stump at rest and after walking, and summarize this information with a single 3D differential map. The workflow was tested on a person with transtibial amputation, with a reconstruction accuracy lower than 3 mm, which is adequate for socket adaptation. We expect the workflow to improve socket acceptance and patients' quality of life.

Transtibial prosthetic socket fitting: Australian prosthetist perspectives on primary challenges, management strategies, and opportunities for workflow and technological innovation

BACKGROUND

Following transtibial amputation, a custom-built socket is the most common interface between the prosthesis and residual limb. Desire from both prosthetists and prosthesis users for improved socket fitting processes have been well documented. However, there is currently limited information available about prosthetists' experiences of how prosthetic manufacturing workflow can contribute to socket fit problems.

OBJECTIVES

This study aims to determine how socket fit problems are currently detected and managed by prosthetists and to identify challenges, management strategies, and opportunities for workflow and technological innovation during prosthesis manufacture and socket fitting.

STUDY DESIGN

Mixed-method (quantitative and qualitative) survey.

METHODS

An online survey was developed and piloted in consultation with members of the Australian Orthotic Prosthetic Association. The final 25-question survey was distributed through their membership database. Mixed methods were used to analyze survey items. Qualitative items were grouped and coded under themes relating to challenges, management strategies, and opportunities. Quantitative data were analyzed using nonparametric descriptive methods.

RESULTS

Twenty-three respondents with a range of experience completed the survey. Seven of eight major Australian states/territories were represented. Primary workflow stages presenting challenges with limited strategies/solutions available to the prosthetists were roll-on liner selection, mold or cast modifications, communication with the client, and check socket fitting. Suggested solutions included improved socket-limb interface monitoring technology.

CONCLUSIONS

This study provides the first insights into prosthetist-identified challenges and limitations at different stages of the socket workflow and presents a starting point for more targeted research into innovation that may assist in these processes.

Recommendations from the ISPO lower-limb COMPASS: Patient-reported and performance-based outcome measures

BACKGROUND

Outcome measures (patient-reported and performance-based) are used widely but not uniformly within the clinical setting for individuals with lower-limb absence (LLA). The need for more detailed information by funding bodies, service planners and providers, and researchers requires the systematic and routine use of outcome measures. Currently, there is no consensus on which outcome measure(s) should be used for individuals with LLA. The aim of the International Society of Prosthetics and Orthotics (ISPO) lower-limb Consensus Outcome Measures for Prosthetic and Amputation Services (COMPASS) was to produce a recommended list of outcome measures to be actively promoted for routine use within clinical practice before and after an episode of care.

METHODS

Between May and June 2021, 46 users, clinicians, researchers, managers, and policymakers working in the field of LLA and prosthetic users met virtually. Consensus participants were first asked to complete an online survey with questions based on the results from a systematic review and the outcomes from an expert panel. A modified Delphi technique was used to determine outcome measures for use in routine clinical practice. This paper discusses the ISPO lower-limb COMPASS process from which recommendations were made.

RESULTS

The ISPO lower-limb COMPASS resulted in the following 6 recommendations: (1) Amputee Mobility Predictor, Timed Up and Go, Two-Minute Walk Test, Prosthetic Evaluation Questionnaire-Residual Limb Health, Prosthetic Evaluation Questionnaire-Utility, and Trinity Amputation and Prosthesis Experience Scales-Revised, which make up the ISPO lower-limb COMPASS ; (2) Comprehensive High-Level Activity Mobility Predictor and Six-Minute Walk Test are 2 additional outcome measures recommended for higher-activity-level individuals with LLA, which make up the COMPASS+ ; (3) Patient-Specific Function Scale makes up the COMPASS Adjunct ; (4) a generic health-related quality of life outcome measure such as the European Quality of Life-5D-5L or Patient-Reported Outcomes Measurement Information System-29 item can be used to supplement the COMPASS; (5) outcome measures suited to low- and middle-income countries need to be developed with a focus on activities such as sitting cross-legged, kneeling, squatting, and other culturally important mobility-related activities; and (6) translation, validation, and open sharing of translated outcome measures included in the COMPASS, COMPASS+, and COMPASS Adjunct occurs.

CONCLUSION

The above recommendations represent the current status of knowledge on outcome measures for LLA based on research and international consensus and hence, will change over time. This work has been developed for clinicians and researchers to improve knowledge on outcome measures to guide clinical decision-making and future research initiatives.

Optimal design and 3D printing of prosthetic socket based on the interface pressure between the socket and residual limb

BACKGROUND

At present, the quantifiable pressure distribution at the interface between the socket and stump is seldom applied in the design and fabrication of the socket.

OBJECTIVES

This study aimed to optimize the socket based on the interface pressure of residual limb-socket, thereby avoiding excessive local load on the residual limb, reducing the load on the pressure-sensitive (PS) regions and making the limb more evenly loaded.

METHODS

The residual limb was divided into the main load-bearing regions, the pressure-tolerant regions, and the PS regions according to the carrying capacity at its different regions. Based on these bearing regions, a mathematical function was developed, which applied modifications/adjustments to the socket design in a Computer Aided Design (CAD) environment by using the adjustment function. Besides, three adjusted sockets were produced by using selective laser sintering 3D printing technology.

RESULTS

The wearing of the 3D-adjusted printed sockets reduced the contact interface pressures in the distal tibial region and the fibular head region by 85.6% and 84.4%, respectively. In addition, the walking distance of the subject was increased by 18.34%, and the overall pressure distribution on the stump became more uniform.

CONCLUSIONS

The pressures in the original overpressure regions and the PS regions could reduce, whereas the pressure in the low-load regions of main load-bearing or pressure-tolerant regions could increase by modifying the socket with the pressure adjustment function. At the same time, the pressure among different regions was more uniform except for the sensitive regions.

Facilitators and Barriers That Transfemoral Amputees Experience in Their Everyday Life: A Norwegian Qualitative Study

Background

Living with a lower limb amputation influences multiple facets of life due to altered function. Individuals achieve a varied level of function post amputation, depending on several variables like age, level of function prior to amputation, and available personal and environmental resources. Releasing the potential to live life to the fullest despite a disability is important to the individual.

Objectives

The primary objective of this study is to identify barriers and facilitators for function which lower limb amputees experience in their lives several years after amputation, from the amputee's perspective. This knowledge can contribute to further development of the clinical pathway for lower limb amputees in a Norwegian rehabilitation hospital.

Methods

The study has a descriptive and exploratory qualitative design with a phenomenological hermeneutical approach. Semistructured, individual interviews were conducted for data collection. Thematic analysis inspired by Braun and Clarke was used for data analysis. The sample consisted of eight transfemoral amputees (70 ± 6.9 (58-77 years)) living in the southern part of Norway. Average time since amputation was 11 years.

Results

The results have been categorised into two main themes with subthemes: (1) facilitators: personal resources, a well-fitted prosthesis, rehabilitation, social network, balance in activity/rest, and accessibility and (2) barriers: walking distance, poorly fitted prosthesis, pain, comorbidities, climate/terrain/falling, reduced local competence on amputation, and pandemic.

Conclusion

Lower limb amputees experience barriers in their everyday life, but they also develop strategies to cope with their disability. Clinical implications can include increased nutritional guidance, structural psychological mapping and follow-up, structured follow-ups over a significant period of time, and extended use of digital consultation.

Design and evaluation of a prosthetic socket for a patient with diabetic-related transtibial amputation: A case report

This is a report of a diabetic transtibial amputee with severe pain and ulcer in the antero-distal of the tibia. A novel prosthetic socket with an antero-distal silicone wall was designed. The result showed that the patient's satisfaction was increased and the average peak pressure was reduced by using the new socket design.

Foot contact forces can be used to personalize a wearable robot during human walking

Individuals with below-knee amputation (BKA) experience increased physical effort when walking, and the use of a robotic ankle-foot prosthesis (AFP) can reduce such effort. The walking effort could be further reduced if the robot is personalized to the wearer using human-in-the-loop (HIL) optimization of wearable robot parameters. The conventional physiological measurement, however, requires a long estimation time, hampering real-time optimization due to the limited experimental time budget. This study hypothesized that a function of foot contact force, the symmetric foot force-time integral (FFTI), could be used as a cost function for HIL optimization to rapidly estimate the physical effort of walking. We found that the new cost function presents a reasonable correlation with measured metabolic cost. When we employed the new cost function in HIL ankle-foot prosthesis stiffness parameter optimization, 8 individuals with simulated amputation reduced their metabolic cost of walking, greater than 15% (p < 0.02), compared to the weight-based and control-off conditions. The symmetry cost using the FFTI percentage was lower for the optimal condition, compared to all other conditions (p < 0.05). This study suggests that foot force-time integral symmetry using foot pressure sensors can be used as a cost function when optimizing a wearable robot parameter.

Evaluation of the new, patient-adjustable socket system Varos in the early phase of prosthetic rehabilitation: a pilot study

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.

Measurements of Best, Worst, and Average Socket Comfort Are More Reliable Than Current Socket Comfort in Established Lower Limb Prosthesis Users

OBJECTIVE

To evaluate test-retest reliability and related measurement properties of items developed to assess best, worst, and average prosthetic socket comfort.

DESIGN

Methodological research to assess test-retest reliability of 4 individual socket comfort survey items. Socket comfort items were included in a self-report paper survey, which was administered to participants 2 to 3 days apart.

SETTING

General community.

PARTICIPANTS

A minimum convenience sample of participants (N=63) was targeted for this study; 72 lower limb prosthesis users (>1y postamputation) completed the survey and were included in the final dataset.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

The expanded socket comfort score (ESCS) was adapted from the original socket comfort score (SCS). The original SCS is a single-item self-report instrument developed to assess a lower limb prosthesis user's current socket comfort. Three additional items were designed to assess the user's best, worst, and average socket comfort over the previous 7 days.

RESULTS

Best, worst, and average socket comfort items demonstrated better reliability, as indicated by higher intraclass correlation coefficients. As such, these items also exhibited lower measurement error and smaller minimal detectable change values than the item that measured current socket comfort. However, test-retest coefficients for all 4 ESCS items were below the level desired for evaluation of within-individual changes of socket comfort.

CONCLUSIONS

Items that assess best, worst, and average comfort provide a more stable measurement of socket fit than the existing SCS instrument. Although administration of all 4 ESCS items may provide more comprehensive assessment of a lower limb prosthesis user's socket fit, administrators should expect variations in scores over time owing to the variable nature of the underlying construct over time. Future research should examine whether the ESCS provides an improved overall assessment of socket fit.

The Impact of Limited Prosthetic Socket Documentation: A Researcher Perspective

The majority of limb prostheses are socket mounted. For these devices, the socket is essential for adequate prosthetic suspension, comfort, and control. The socket is unique among prosthetic components as it is not usually mass-produced and must instead be custom-made for individual residual limbs by a prosthetist. The knowledge of what constitutes "good" socket fit is gained by expert prosthetists and technicians over years of experience, and rarely documented. The reliance on tacit knowledge makes it difficult to standardize the criteria for a well-fitting socket, leading to difficulties understanding the impact of socket fit. Despite its importance, the workflow for socket fitting is often overlooked in literature. Due to the customized nature of sockets, if information is provided in literature, generally only the type of socket and suspension mechanism is noted, with information regarding the fitting and manufacturing processes omitted. In this article, the concerns, issues and consequences arising from lack of upper and lower limb socket documentation are discussed from a researcher perspective, supported by healthcare professionals and socket fabrication specialists. Key changes are proposed to the way socket manufacturing and evaluation are documented to assist future research.

Measuring discomfort-An objective method for quantifying peak pressure discomfort and improved fit in adults with transtibial amputation

BACKGROUND

Prosthetic socket coupling with the residual limb should be comfortable without causing skin breakdown or excessive pressure. However, users report socket discomfort, and there is a scarcity of objective measurements available to assess this feeling of discomfort. Quantifying the specific pressure may enable clinicians and users to determine and improve comfort levels objectively.

OBJECTIVES

(1) To evaluate if a peak pressure reduction assists in resolving wounds, redness, and pain inside prosthetic sockets in people with transtibial amputation. (2) To determine if peak pressures measured inside the prosthetic socket due to external forces could be used to quantify the level of improvement in socket discomfort.

DESIGN

In this cohort study, we used a pressure sensor to quantify and facilitate adjustments to the prosthetic socket, correlating this information to the user's socket comfort.

SETTING

Outpatient clinic in a tertiary hospital in Singapore.

PARTICIPANTS

People (N = 16) with unilateral transtibial lower limb amputation using a prosthesis.

INTERVENTIONS

NA.

MAIN OUTCOME MEASURES

Peak pressure and socket comfort score (SCS).

RESULTS

The peak pressure value showed a statistically significant reduction across all participants following adjustments at a 50% delta change in pressure (p = .001). This was achieved with a mean number of 2.6 ± 1.4 adjustments per participant. Following the adjustments, the paired t-test results showed a mean increase between the first SCS and final SCS was 2.6 (p = .001).

CONCLUSION

The wound, redness, and pain resolved in 15 of 16 participants regardless of diabetic status following socket adjustments. Although the peak pressures values did not correlate to the SCS score, the reduction in peak pressure saw significant improvement to the SCS. The use of a portable sensor is a fast and efficient means to quantify adjustments inside the prosthetic socket and could potentially be considered as part of future care delivery.

Deleterious Musculoskeletal Conditions Secondary to Lower Limb Loss: Considerations for Prosthesis-Related Factors

Significance: The intent of this work was to summarize the existing evidence of, and highlight knowledge gaps specific to, prosthetic devices/componentry and training regimes, particularly in the context of the human-device interaction and deleterious musculoskeletal conditions secondary to lower limb loss. Recent Advances: With the recent and evolving technological advancements in prostheses, there are numerous devices available to individuals with lower limb loss. Current literature demonstrates the importance of expanding the knowledge of all prosthetic device-specific factors and the significance of proper prescription, fit, and alignment, along with adequate device-/activity-specific training, to enhance human-device interaction, reduce gait abnormalities and compensatory motions, and as a result, mitigate risk for secondary musculoskeletal conditions. Critical Issues: Inadequate device prescription, fit, alignment, and training are evident owing to the lack of knowledge or awareness of the many device-specific properties and factors, leading to suboptimal use, as well as, biomechanical compensations, which collectively and adversely affect the function, activity level, and overall health of the prosthesis user. Future Directions: To maximize optimal outcomes after lower limb loss, it is essential to better appreciate the factors that affect both prosthesis use and satisfaction, particularly any modifiable factors that might be targeted in rehabilitation interventions such as device prescription, fit/alignment, and training regimes. A better understanding of such device-specific factors will help enhance the human-device interaction and resulting functional performance, thereby reducing secondary musculoskeletal conditions, allowing for the readiness of the fighting force (return-to-duty/redeployment) and/or improved reintegration into civilian society/work, and overall enhancing quality of life after lower limb loss.

A Biomimetic Adapter for Passive Self-alignment of Prosthetic Feet

INTRODUCTION

Dynamic alignment of lower limb prostheses is subjective and time-consuming. Compensatory gait strategies caused by prosthesis misalignment can negatively affect lower limb amputees who cannot access a certified prosthetist for alignment adjustments. The objective of this study is to evaluate a novel six-degrees-of-freedom passive transtibial prosthetic adapter that self-aligns during various phases of gait. This self-aligning adapter may benefit service members and veterans stationed or living far from a clinical facility.

METHODS

Four transtibial amputee subjects, aged 47 to 62 (mean: 55.75) years with mean weight of 163.6 lbs and mean K-level of 3.25, walked at self-selected speeds on a 10-m level walkway. Subjects walked with the self-aligning and a size- or weight-matched control adapter, assembled to a commercially available energy-storing-and-returning foot and their own socket, with 22-mm alignment perturbations in the anterior, posterior, medial, or lateral directions. Subjects were blinded to both adapter type and misalignment. Socket moments, spatiotemporal gait parameters, and subjective socket comfort were recorded.

RESULTS

Preliminary results showed improvements in mean peak socket moments and step length differential with the self-aligning adapter across all alignments. Walking speed and prosthesis-side base of support showed little change in all configurations. Prosthesis-side stance duration and Functional Ambulation Profile Score increased with the self-aligning adapter in some alignments. Patient-reported socket comfort increased slightly with the self-aligning adapter across all misalignments.

CONCLUSION

Subjects maintained similar walking speeds and experienced greater gait symmetry and reduced sagittal plane peak moments with the self-aligning adapter when exposed to misalignments. These trends suggest a benefit to transtibial amputees from a reduction in secondary gait effects from prosthesis misalignments. Additionally, a wider range of acceptable prosthesis alignments may be possible with the self-aligning adapter. Subsequent trials are underway to evaluate the self-aligning adapter in real-world environments like walking on uneven terrains, stairs, ramps, and abrupt turns.

The comprehensive lower limb amputee socket survey: Reliability and validity of the persian version

BACKGROUND

The Comprehensive Lower limb Amputee Socket Survey (CLASS) is a self-reported measure developed to assess prosthetic socket fit in individuals with lower limb amputation.

OBJECTIVE

To assess the reliability and validity of the Persian version of the CLASS.

STUDY DESIGN

Cross-sectional and repeated-measures.

METHODS

We evaluated the translation and back translation of the CLASS and made the required changes according to expert committee feedback. Then, we recruited 124 participants with unilateral lower limb amputation (89.5% men). Internal consistency was analyzed with Cronbach's alpha and test-retest reliability using intra-class correlation coefficients. Convergent construct validity was assessed by comparing the CLASS scores with the Persian version of the Trinity Amputation and Prosthesis Experience Scales (TAPES) scores. In addition, known groups construct validity was assessed by comparing CLASS scores between groups with different causes and levels of amputation.

RESULTS

Cronbach's alpha coefficient represented a very good internal consistency for all domains of the Persian CLASS (ranged from 0.86 to 0.92). The intra-class correlation coefficient for test-retest reliability for the Persian CLASS was good to excellent (ranged from 0.73 to 0.97). There was a significant correlation between the subscales of the Persian CLASS and satisfaction subscales of the Persian TAPES (p < 0.001). There was significant difference between comfort subscale of the Persian CLASS scores by level of amputation.

CONCLUSION

The Persian CLASS is a reliable and valid measure for evaluating prosthetic socket fit.

A toolkit for prosthetists and orthotists to facilitate progress in professional communication over the next 50 years

BACKGROUND

In this celebratory issue of Prosthetics and Orthotics International, we review professional communication skills in the field of prosthetics and orthotics.

OBJECTIVE

We aim to reflect on communication skills in the past 50 years, to discuss developments in the coming 50 years, and to create a toolkit and research agenda to facilitate progress in professional communication in the next 50 years.

RESULTS

Despite being a key area in prosthetics and orthotics training programmes, we found no studies on professional communication with an experimental design published in Prosthetics and Orthotics International. As an alternative, we provide clinical reflections on the changes in professional communication in the past 50 years, and we discuss questionnaire-based and qualitative studies that provide evidence for the importance of communication in pedorthic footwear provision. In the coming 50 years, professional communication in the field of prosthetics and orthotics may be impacted by aging populations, global mobility, information technology, technological advances and emphasis on prevention. We discuss each of these topics. To facilitate progress in professional communication, we have created a toolkit with resources for prosthetics and orthotics professionals, prosthetics and orthotics students and other interested professionals.

CONCLUSIONS

We hope this toolkit will inspire others to use, extend and implement it in their daily practice. As a research agenda, we strongly recommend undertaking research on interventions to improve professional communication and to study its effect on clinically meaningful outcomes.

Clinical utility of pressure feedback to socket design and fabrication

BACKGROUND

The clinical utility of measuring pressure at the prosthetic socket-residual limb interface is currently unknown.

OBJECTIVES

This study aimed to identify whether measuring interface pressure during prosthetic design and fabrication results in closer agreement in pressure measurements between sockets made by different clinicians, and a reduction in pressure over areas of concern. It also investigated whether clinicians value knowing the interface pressure during the fabrication process.

STUDY DESIGN

Mixed methods.

METHODS

Three prosthetists designed a complete prosthetic system for a transtibial residual limb surrogate. Standardised mechanical testing was performed on each prosthetic system to gain pressure measurements at four key anatomical locations. These measurements were provided to the clinicians, who subsequently modified their sockets as each saw fit. The pressure at each location was re-measured. Each prosthetist completed a survey that evaluated the usefulness of knowing interface pressures during the fabrication process.

RESULTS

Feedback and subsequent socket modifications saw a reduction in the pressure measurements at three of the four anatomical locations. Furthermore, the pressure measurements between prosthetists converged. All three prosthetists found value in the pressure measurement system and felt they would use it clinically.

CONCLUSIONS

Results suggest that sensors measuring pressure at the socket-limb interface has clinical utility in the context of informing prosthetic socket design and fabrication. If the technology is used at the check socket stage, iterative designs with repeated measurements can result in increased consistency between clinicians for the same residual limb, and reductions in the magnitudes of pressures over specific anatomical landmarks.

CLINICAL RELEVANCE

This study provides new information on the value of pressure feedback to the prosthetic socket design process. It shows that with feedback, socket modifications can result in reduced limb pressures, and more consistent pressure distributions between prosthetists. It also justifies the use of pressure feedback in informing clinical decisions.