Returning to work after dysvascular lower limb amputation-A novel multivariate approach to examine relative contributions of biopsychosocial predictors.

BACKGROUND: Returning to work is a key outcome of rehabilitation and social re-integration after lower limb amputation. It is important to understand what biopsychosocial factors contribute to returning to work after dysvascular amputation. OBJECTIVE: Examining relative contributions of functional and contextual predictors of returning to work in participants with lower limb amputation due to diabetes and other dysvascular diseases. STUDY DESIGN: Cross-sectional. METHODS: Return-to-work outcome, biopsychosocial characteristics including physical functioning, self-efficacy & perceived ability, and socioeconomical support data were collected from a purposive sample (n = 57) in a multi-state collaborative research network. Grouped Weighted Quantile Sum model analysis was conducted to evaluate relative contributions of biopsychosocial predictors. RESULTS: Less than 30% of the participants returned to work after their amputation. Physical functioning (odds ratio = 10.19; 95% CI 2.46-72.74) was the most important predictor group. Working before amputation, prosthetic mobility, and access to rehabilitation care were also identified as key factors associated with returning to work. CONCLUSIONS: Fewer than 1 in 3 participants with dysvascular amputation returned to work, despite an average age of only 54 years at the time of amputation. Physical functioning was shown to be the most important predictor, while socioeconomic factors such as a lack of access to care also contribute to not returning to work after dysvascular amputation.

Association of Race, Ethnicity, and Gender to Disparities in Functional Recovery and Social Health After Major Lower Limb Amputation: A Cross-sectional Pilot Study.

OBJECTIVE: To assess if evidence of disparities exists in functional recovery and social health post-lower limb amputation. DESIGN: Race-ethnicity, gender, and income-based group comparisons of functioning and social health in a convenience sample of lower limb prosthetic users. SETTING: Prosthetic clinics in 4 states. PARTICIPANTS: A geographically diverse cohort of 56 English and Spanish speaking community-dwelling individuals with dysvascular lower limb amputation, between 18-80 years old. INTERVENTIONS: None. MAIN OUTCOMES MEASURES: Primary outcomes included 2 physical performance measures, the Timed Up and Go test and 2-minute walk test, and thirdly, the Prosthetic Limb Users Survey of Mobility. The PROMIS Ability to Participate in Social Roles and Activities survey measured social health. RESULTS: Of the study participants, 45% identified as persons of color, and 39% were women (mean ± SD age, 61.6 (9.8) years). People identifying as non-Hispanic White men exhibited better physical performance than men of color, White women, and women of color by -7.86 (95% CI, -16.26 to 0.53, P=.07), -10.34 (95% CI, -19.23 to -1.45, P=.02), and -11.63 (95% CI, -21.61 to -1.66, P=.02) seconds, respectively, on the TUG, and by 22.6 (95% CI, -2.31 to 47.50, P=.09), 38.92 (95% CI, 12.53 to 65.30, P<.01), 47.53 (95% CI, 17.93 to 77.13, P<.01) meters, respectively, on the 2-minute walk test. Income level explained 14% and 11% of the variance in perceived mobility and social health measures, respectively. CONCLUSIONS: Study results suggest that sociodemographic factors of race-ethnicity, gender, and income level are associated with functioning and social health post-lower limb amputation. The clinical effect of this new knowledge lies in what it offers to health care practitioners who treat this patient population, in recognizing potential barriers to optimal recovery and quality of life. More work is required to assess lived experiences after amputation and provide better understanding of amputation-related health disparities.

A pilot study comparing prosthetic to sound limb gait mechanics during a turning task in people with transtibial amputation.

BACKGROUND: Observational gait analysis is frequently used by clinicians to subjectively assess straight walking but is not often used to examine turning. Interlimb comparisons of phase- specific turning biomechanics in people with unilateral lower limb amputation has not previously been documented. METHODS: A retrospective examination of gait kinematics and kinetics from five participants with unilateral transtibial amputation was performed. Data were collected during 90° step and spin turns capturing three distinct turning steps. Gait metrics of interest included: total turn time, stance time, peak knee flexion angle during Pre-Swing and Initial Swing gait phases, peak hip flexion and extension, ground reaction impulse, and whole body angular momentum. Statistical comparisons were made based on turn type between sound and prosthetic limbs. FINDINGS: During the three turn steps (approach, apex, depart), participants spent significantly more time (P < 0.01) on their sound limb compared to their prosthetic limb regardless of turn type. Additionally, the prosthetic limb hip and knee exhibited more flexion (P < 0.05) during the apex step of turns, and whole body angular momentum was higher when the sound limb was used during the apex step of a turn (P < 0.05). INTERPRETATION: This descriptive study offers the first phase-specific quantification of turning biomechanics in people with lower limb amputation. Results indicate that people with unilateral transtibial amputation spend more time on and experience higher impulses through their sound compared to their prosthetic limb during 90° turns, and that the prosthetic limb is performing differently than the sound limb, potentially increasing risks of injury or falls.

Comparison of prosthetic mobility and balance in transfemoral amputees with bone-anchored prosthesis vs. socket prosthesis.

BACKGROUND: The literature comparing bone-anchored prosthesis (BAP) with socket prosthesis (SP) consistently reports improvement in physical health and quality of life using primarily patient-reported outcome measures (PROMs). OBJECTIVE: To determine the differences in mobility and balance using performance-based outcome measures and PROMs in people with transfemoral amputations (TFAs) fitted with BAP vs. SP. STUDY DESIGN: Causal comparative. METHODS: Two groups of people with TFAs were recruited: one using a BAP (N = 11; mean age ± standard deviation, 44 ± 14.9 years; mean residual limb length as a percentage of the intact femur, 68% ± 15.9) and another group using a SP (N = 11; mean age ± standard deviation, 49.6 ± 16.0 years; mean residual limb length as a percentage of the intact femur, 81% ± 13.9), and completed the 10-meter walk test, component timed-up-and-go, Prosthetic Limb Users Survey of Mobility™ 12-item, and Activities-specific Balance Confidence Scale. RESULTS: There were no statistically significant differences between the BAP and SP groups in temporal spatial gait parameters and prosthetic mobility as measured by the 10-meter walk test and component timed-up-and-go, yet large effect sizes were found for several variables. In addition, Activities-specific Balance Confidence Scale and Prosthetic Limb Users Survey of Mobility™ scores were not statistically different between the BAP and SP groups, yet a large effect sizes were found for both variables. CONCLUSIONS: This study found that people with TFA who use a BAP can demonstrate similar temporal spatial gait parameters and prosthetic mobility, as well as self-perceived balance confidence and prosthetic mobility as SP users. Therefore, suggesting that the osseointegration reconstruction surgical procedure provides an alternative option for a specific population with TFA who cannot wear nor have limitations with a SP. Future research with a larger sample and other performance-based outcome measures and PROMs of prosthetic mobility and balance would further determine the differences between the prosthetic options.

Disparities in functional recovery after dysvascular lower limb amputation are associated with employment status and self-efficacy.

PURPOSE: Employment status is considered a determinant of health, yet returning to work is frequently a challenge after lower limb amputation. No studies have documented if working after lower limb amputation is associated with functional recovery. The study's purpose was to examine the influence of full-time employment on functioning after lower limb amputation. METHODS: Multisite, cross-sectional study of 49 people with dysvascular lower limb amputation. Outcomes of interest included performance-based measures, the Component Timed-Up-and-Go test, the 2-min walk test, and self-reported measures of prosthetic mobility and activity participation. RESULTS: Average participant age was 62.1 ± 9.7 years, 39% were female and 45% were persons of color. Results indicated that 80% of participants were not employed full-time. Accounting for age, people lacking full-time employment exhibited significantly poorer outcomes of mobility and activity participation. Per regression analyses, primary contributors to better prosthetic mobility were working full-time (R2 ranging from 0.06 to 0.24) and greater self-efficacy (R2 ranging from 0.32 to 0.75). CONCLUSIONS: This study offers novel evidence of associations between employment and performance-based mobility outcomes after dysvascular lower limb amputation. Further research is required to determine cause-effect directionalities. These results provide the foundation for future patient-centered research into how work affects outcomes after lower limb amputation. IMPLICATIONS FOR REHABILITATIONLower limb amputation can pose barriers to employment and activity participation, potentially affecting the quality of life.This study found that the majority of people living with lower limb amputation due to dysvascular causes were not employed full-time and were exhibiting poorer prosthetic outcomes.Healthcare practitioners should consider the modifiable variable of employment when evaluating factors that may affect prosthetic mobility.The modifiable variable of self-efficacy should be assessed by healthcare professionals when evaluating factors that may affect prosthetic mobility.

Using theoretical frameworks to examine fall history and associated prosthetic mobility in people with nondysvascular lower limb amputation.

BACKGROUND: Over a million people live with lower limb amputation (LLA) in the United States, and many of them will experience a fall in the next year. The aim of this study was to use existing theoretical frameworks in an attempt to organize the complex interactions of reported fall history and prosthetic mobility in community-ambulating people with LLA. METHODS: Self-reported fall rate and fall circumstances were recorded in a cross-section of people with unilateral LLA due to nondysvascular causes. Self-report and performance-based standardized outcome measures assessed prosthetic mobility and balance confidence. All variables were considered and appropriately placed within a proposed International Classification of Functioning, Disability, and Health framework while using a fall-type classification framework to classify fall circumstances. RESULTS: Information from 69 participants was analyzed. The reported fall rate was at 46%, with those with transfemoral amputation reporting significantly more falls than those with transtibial amputation ( P = 0.001). Tripping over an object was the most common cause (62.5%), and fallers reported significantly lower perceived prosthetic mobility than nonfallers ( P = 0.001). Despite reporting high levels of balance confidence, results indicate that all groups of fallers and nonfallers are at increased fall risk according to performance-based prosthetic mobility score cutoffs. CONCLUSIONS: Community-dwelling people with nondysvascular LLA are at increased fall risk. Classifying fall-related variables using theoretical frameworks provides a means to structure more informative fall risk surveys for people with LLA in an attempt to identify those at greater risk for falling and its potential detrimental effects.

Usability Assessment of the Rehabilitation Lower-limb Orthopedic Assistive Device by Service Members and Veterans With Lower Limb Loss.

INTRODUCTION: Telehealth is an increasingly common approach to improve healthcare delivery, especially within the Veterans Health Administration and Department of Defense (DoD). Telehealth has diminished many challenges to direct access for clinical follow-up; however, the use of mobile telehealth for specialty rehabilitative care is emerging and is referred to as telerehabilitation. As early adopters of telehealth, the Veterans Affairs and DoD have supported collaborated efforts for programs designed to increase the access and quality of rehabilitative care while improving the functional ability of our service members (SMs) and veterans with lower limb amputation (LLA). The DoD and Veterans Health Administration collaborated on a Mobile Device Outcomes-based Rehabilitation Program (MDORP) to help injured SMs and veterans with LLA. The MDORP project utilized a mobile health system called the Rehabilitative Lower Limb Orthopedic Accommodating Device (ReLOAD) to assess walking quality. The ReLOAD system includes real-time auditory biofeedback to notify the user of their most prominent gait deviation and then recommends exercises that address specific balance and strength impairments. The purpose of this study was to describe the responses to a postintervention survey evaluating the feasibility and usability of ReLOAD completed by SMs and veterans with LLA who used the system for 5 months. MATERIALS AND METHODS: A link to an anonymous usability survey was emailed to all participants who completed MDORP. The survey was modeled after the System Usability Scale, with agreeableness to items rated on a 5-point Likert-style questionnaire in addition to open feedback. Data visualization of Likert-style questionnaires was conducted using ggplot2 and reshape2 statistical packages and was analyzed using R. We obtained institutional review board approval through both Miami Veterans Affairs Healthcare System and Walter Reed National Military Medical Center. RESULTS: The majority of participants reported that they would use the system again for home rehabilitation (65%) and that auditory biofeedback helped them walk better (59%). Participants also suggested that future work should include a greater variety of exercise options and the use of smart phones for the ReLOAD application in addition to the iPad tablet. CONCLUSIONS: The participants provided positive and constructive feedback that will enhance the value and usability of telerehabilitation interventions like the ReLOAD system for future users.

The Relationship Between Vestibular Sensory Integration and Prosthetic Mobility in Community Ambulators With Unilateral Lower Limb Amputation.

OBJECTIVE: The modified Clinical Test of Sensory Interaction and Balance (mCTSIB) is used to clinically assess vestibular sensory integration (VSI), the process by which the central nervous system integrates vestibular afference to maintain balance. The rate and effects of impaired VSI (IVSI) on prosthetic mobility in people with lower limb amputation (LLA) is unknown. The objective of this study was to use the mCTSIB to classify VSI in active community ambulators with LLA and to examine the relationship between IVSI and prosthetic mobility, as measured by the Component Timed Up and Go (cTUG) test. METHODS: This was a cross-sectional study with a convenience sample of 130 community ambulators with unilateral LLA. Classification of VSI was determined based on a time-based pass/fail mCTSIB performance. Participants were classified as having normal sensory integration (NSI) if they could balance for 30 seconds in every mCTSIB condition. Participants who failed condition 4 exclusively were classified as IVSI. Prosthetic mobility, as measured by the cTUG, was compared between NSI and IVSI groups. RESULTS: Of the 130 participants, 29 (22%) were classified as IVSI and 95 (73%) were classified as having NSI. Prosthetic mobility significantly differed between IVSI and NSI groups, with IVSI participants performing all components of the cTUG significantly slower. Medium to large effect sizes were found between groups during cTUG. CONCLUSIONS: These results suggest that 1 in 5 community ambulators with LLA have IVSI, with associated limitations in balance confidence and prosthetic mobility. IMPACT: The ability to integrate vestibular information was found to have a strong relationship with prosthetic mobility in active community ambulators with LLA, especially with performing a 180-degree step turn. Physical therapists can use the mCTSIB to classify sensory integration during prosthetic rehabilitation and develop an appropriate balance intervention. LAY SUMMARY: Active adults with LLA can use information from their senses to maintain their standing balance. Adults with LLA who have difficulty balancing on foam with closed eyes were slower to get in and out of a chair, walk, and perform a 180-degree step turn.

The Effectiveness of the DoD/VA Mobile Device Outcomes-Based Rehabilitation Program for High Functioning Service Members and Veterans with Lower Limb Amputation.

INTRODUCTION: The objective was to determine if the Mobile Device Outcomes-based Rehabilitation Program (MDORP) improved strength, mobility, and gait quality in service members (SMs) and Veterans with lower limb amputation (LLA). METHODS: Seven SMs and 10 Veterans with LLA enrolled and were trained to use a mobile sensor system, called Rehabilitative Lower Limb Orthopedic Analysis Device (ReLOAD). ReLOAD provided participants with real-time assessment of gait deviations, subsequent corrective audio feedback, and exercise prescription for normalizing gait at home and in the community. After baseline testing, prosthetic gait and exercise training, participants took ReLOAD home and completed an 8-week walking and home exercise program. Home visits were conducted every 2 weeks to review gait training and home exercises. RESULTS: Significant improvements in hip extensor strength, basic and high-level mobility, musculoskeletal endurance, and gait quality (P < 0.05) were found at the completion of the 8-week intervention. CONCLUSION: Preliminary MDORP results are promising in its ability to improve basic and high-level mobility, lower limb strength, and gait quality in a group of SMs and Veterans with LLA. In addition, "booster" prosthetic training may be justified in an effort helps maintain an active lifestyle, promotes prosthetic use, and mitigates secondary health effects.

Current and Emerging Trends in the Management of Fall Risk in People with Lower Limb Amputation.

PURPOSE OF REVIEW: People living with lower limb amputation are at an increased risk of falling compared with the healthy geriatric population. Factors of increased age and increased number of comorbidities could compound the already increased risk. The purpose of this article is to highlight recent research associated with fall risk in amputees and provide the reader with evidence to help guide clinical interventions. RECENT FINDINGS: Though research on the topic of falls in people with amputation is becoming more common, there is still a dearth of evidence regarding what contributes to increased fall risk and how to address it in this population. There are recent studies that have examined therapy and prosthetic interventions that could mitigate fall risk in people with amputation, yet there is not enough evidence to develop a consensus on the topic. More research is required to determine what contributes to increased fall rates in people with amputation, and what detriments to an amputee's function or psyche may result after incurring a fall. SUMMARY: Borrowing from what is known about geriatric fall risk and combining the information with novel and existing approaches to fall mitigation in amputees can offer clinicians the opportunity to develop evidence-based programs to address fall risk in their patients with lower limb amputation.

Variables that Influence Basic Prosthetic Mobility in People With Non-Vascular Lower Limb Amputation.

BACKGROUND: There exists a dearth of evidence on rehabilitation factors that influence prosthetic mobility in people with lower limb amputation (LLA). Examining variables that contribute to prosthetic mobility can inform rehabilitation interventions, providing guidance in developing more comprehensive care for these individuals. OBJECTIVE: To determine the influence of modifiable and non-modifiable variables related to LLA and their impact on prosthetic mobility, using the International Classification of Functioning, Disability and Health (ICF) model. Secondarily, to determine if personal factors and self-reported balance and mobility are predictive of Component timed-up-and-go (cTUG) performance. DESIGN: Cross-sectional study of a convenience sample. SETTING: National conference. PARTICIPANTS: People (N=68) with non-vascular causes of unilateral LLA. METHODS: Assessment of anthropometrics, mobility, bilateral hip extensor strength, hip range of motion, single limb balance, and self report measures. Lasso linear regression and extreme gradient boosting analyses were used to determine influence of variables on prosthetic mobility. MAIN OUTCOME MEASURE: Timed performance of the cTUG. RESULTS: The following five variables were found to influence basic prosthetic mobility (P ≤ .05) in people with transtibial amputation: hip extensor strength, hip range of motion, single limb balance, waist circumference, and age. In the transfemoral cohort, number of comorbidities and waist circumference primarily influenced prosthetic mobility. Additionally, 66% of the variance in cTUG total time for the entire sample could be explained by simply regressing on level of amputation, number of comorbidities, age and Activities-specific Balance Confidence scale score, all variables easily collected in a waiting room. CONCLUSION: Variables that are modifiable with physical therapy intervention including hip extensor strength, hip range of motion, single limb balance, and waist circumference significantly influenced basic prosthetic mobility. These variables can be affected by targeted rehabilitation interventions and lifestyle changes. LEVEL OF EVIDENCE: II.

Inertial sensor-based measures of gait symmetry and repeatability in people with unilateral lower limb amputation.

BACKGROUND: People with lower limb amputation often walk with asymmetrical gait patterns potentially leading to long-term health problems, ultimately affecting their quality of life. The ability to discreetly detect and quantify the movement of bilateral thighs and shanks using wearable sensor technology can provide additional insight into how a person walks with a lower limb prosthesis. This study investigated segmental symmetry and segmental repeatability of people with unilateral lower limb amputation, examining performance of the prosthetic and intact limbs. METHODS: Gyroscope signals were recorded from four inertial measurement units worn on bilateral lower limb segments of subjects with unilateral lower limb amputation during the 10-m walk test. Raw angular velocity signals were processed using dynamic time warping and application of algorithms resulting in symmetry measures comparing similarity of prosthetic to intact limb strides, and repeatability measures comparing movement of one limb to its consecutive strides. FINDINGS: Biomechanical differences in performance of the prosthetic and intact limb segments were detected with the segmental symmetry and segmental repeatability measures in 128 subjects. More asymmetries and less consistent movements of the lower limbs were exhibited by subjects with transfemoral amputation versus transtibial amputation (p < .004, Cohen's d = 0.65-1.1). INTERPRETATION: Sensor-based measures of segmental symmetry and segmental repeatability were found to be reliable in detecting discreet differences in movement of the prosthetic versus intact lower limbs in amputee subjects. These measures provide a convenient tool for enhanced prosthetic gait analysis with the potential to focus rehabilitative and prosthetic interventions.

Temporal-Spatial Values During a 180° Step Turn in People with Unilateral Lower Limb Amputation.

BACKGROUND: Daily ambulation with a prosthesis often involves turning to negotiate within the home and community environments, however how people with lower limb loss perform turns is infrequently studied. Administering a common clinical outcome measure to capture turn performance data provides a convenient means of assessing this ubiquitous activity. RESEARCH QUESTION: What temporal-spatial parameters are exhibited by people with unilateral lower limb amputation while performing a 180˚ turn task? METHODS: Forty community-ambulating subjects with unilateral lower limb amputation (20 transtibial amputees, 20 transfemoral amputees) performed the Component Timed-Up-and-Go (cTUG) test turning once in each direction, both toward the intact and toward the prosthetic limb. An instrumented walkway captured temporal-spatial parameters during performance of the 180˚ turn task of the cTUG, while a custom iPad application recorded time and number of steps to perform the turn. Comparisons between turn direction and level of amputation during the cTUG and temporal-spatial results were assessed. RESULTS: People with lower limb amputation spent more time on their intact limb while turning than their prosthetic limb regardless of the position of the intact limb, and those with transfemoral amputation spent significantly more time over the intact limb than those with transtibial amputation. Additionally, subjects with transfemoral amputation performed the turn significantly faster when turning with an inner intact limb. SIGNIFICANCE: Amputees use different movement strategies with altered temporal-spatial characteristics to turn depending on the direction of the turn and the level of amputation. Clinical use of the cTUG could provide evidence supporting prosthetic prescription practice and introduction of novel physical therapy interventions for individuals with lower limb amputation.

The Component Timed-Up-and-Go test: the utility and psychometric properties of using a mobile application to determine prosthetic mobility in people with lower limb amputations.

OBJECTIVE: Using a custom mobile application to evaluate the reliability and validity of the Component Timed-Up-and-Go test to assess prosthetic mobility in people with lower limb amputation. DESIGN: Cross-sectional design. SETTING: National conference for people with limb loss. SUBJECTS: A total of 118 people with non-vascular cause of lower limb amputation participated. Subjects had a mean age of 48 (±13.7) years and were an average of 10 years post amputation. Of them, 54% ( n = 64) of subjects were male. INTERVENTION: None. MAIN MEASURE: The Component Timed-Up-and-Go was administered using a mobile iPad application, generating a total time to complete the test and five component times capturing each subtask (sit to stand transitions, linear gait, turning) of the standard timed-up-and-go test. The outcome underwent test-retest reliability using intraclass correlation coefficients (ICCs) and convergent validity analyses through correlation with self-report measures of balance and mobility. RESULTS: The Component Timed-Up-and-Go exhibited excellent test-retest reliability with ICCs ranging from .98 to .86 for total and component times. Evidence of discriminative validity resulted from significant differences in mean total times between people with transtibial (10.1 (SD: ±2.3)) and transfemoral (12.76 (SD: ±5.1) amputation, as well as significant differences in all five component times ( P < .05). Convergent validity of the Component Timed-Up-and-Go was demonstrated through moderate correlations with the PLUS-M ( rs = -.56). CONCLUSION: The Component Timed-Up-and-Go is a reliable and valid clinical tool for detailed assessment of prosthetic mobility in people with non-vascular lower limb amputation. The iPad application provided a means to easily record data, contributing to clinical utility.