Reliability of the two-minute walk test in individuals with transtibial amputation

Measuring metabolic energy expenditure with short duration walking tests for individuals with lower limb amputation

INTRODUCTION

Metabolic assessment of prosthetic gait is useful when comparing devices, interventions, or populations. However, the standard requirement to walk continuously for six minutes or more to reach steady state (SS) is difficult for many individuals with lower limb amputation. Our goal was to assess the concurrent validity of metabolic outcomes from shorter duration walking tests with those from the standard six-minute walk, in persons with transfemoral or transtibial amputation.

METHODS

Thirty participants (amputation: 10 transfemoral, 10 transtibial, 10 none) performed three walking tests while data were collected with a wearable metabolic system: 1) two-minute treadmill walk plus 10-minute recovery, 2) six-minute treadmill walk, and 3) overground two-minute walk test (2MWT). Three different analyses were performed to correlate SS metabolic outcomes from minutes 5-6 of the six-minute treadmill walk with: 1) total oxygen uptake from the two-minute treadmill walk, incorporating excess post-exercise oxygen consumption (EPOC), 2) minute interval outcomes from minutes 1-4 of the six-minute treadmill walk, and 3) outcomes during minutes 1 and 2 of the 2MWT.

RESULTS

Strong correlations were found between total oxygen uptake of the two-minute treadmill walk plus EPOC and SS oxygen uptake (Pearson r 0.86 to 0.94). Likewise, there were strong correlations between minute interval outcomes of minutes 2, 3, and 4 of the six-minute treadmill walk and SS outcomes (Pearson r 0.82 to > 0.99). Fewer significant correlations were observed when comparing 2MWT outcomes with SS outcomes (Pearson r 0.41 to 0.78).

CONCLUSION

Strong correlations between metabolic outcomes of shorter duration walking tests with SS outcomes suggest that treadmill walking tests as short as two minutes may be acceptable to compare energy expenditure between conditions in individuals with lower limb amputation for circumstances where longer duration tests would not be possible. Additionally, these shorter tests would be more similar to real-life activities and more accessible for those with lower limb amputation.

Translation, cultural adaptation to Brazilian Portuguese, and validation of the Prosthetic Limb Users Survey of Mobility

BACKGROUND

Several outcome measures can be performed to assess and quantify mobility after a lower limb amputation. The Prosthetic Limb Users Survey of Mobility (PLUS-M) is a self-report instrument developed to assess mobility in prosthesis users. It has already been translated into different languages but not into Brazilian Portuguese.

OBJECTIVES

To perform the translation and cultural adaptation into Brazilian Portuguese of the PLUS-M and to assess its validity and reliability.

STUDY DESIGN

Observational cross-sectional study.

METHODS

Translation and cultural adaptation were performed by following internationally recognized standards. To assess construct validity, the T-scores of PLUS-M/12-Item Short Form-Brazilian Portuguese (BR-12) item short form were correlated to the 2-Minute Walk Test and the scores from the Medical Outcomes Study 36-Short Form Health Survey domains by the Spearman correlation coefficient (ρ). A second administration of the PLUS-M/BR-12 was done by phone call to assess test-retest reliability.

RESULTS

Some cultural adaptations were made to improve understanding. The PLUS-M/BR-12 T-scores of 61 participants showed a strong correlation between the scores of the 2-Minute Walk Test (ρ = 0.69) and the Physical Function domain of the 36-Short Form Health Survey (ρ = 0.83), and an excellent test-retest reliability (intraclass correlation coefficient = 0.90 [IC 95% = 0.833-0.943]; F (49,49) = 19,037; P < 0.001).

CONCLUSIONS

The PLUS-M/BR-12 demonstrated evidence of validity and reliability in assessing mobility in Brazilian adults with lower limb amputations who use a prosthetic device, and it is suitable for use in clinical care.

What are relevant predictors of physical activity in older adults with lower limb loss (LLL)? Results of a retrospective analysis

BACKGROUND

People with lower limb loss (LLL) have reduced physical activity (PA). There is evidence of physical and psychosocial predictors of PA in older adults with limb loss. However, these 2 areas (physical/psychosocial) have not been evaluated in the same analysis.

OBJECTIVES

To describe and identify predictors of PA in individuals with LLL.

STUDY DESIGN

Cross-sectional study.

METHODS

Secondary analysis of data from a multisite Canadian randomized control trial involving community-dwelling prosthetic ambulators with unilateral transtibial or transfemoral amputation (N = 72). The dependent variable was the Physical Activity Scale for the Elderly. Potential predictors were four step square test, 2-minute walk test, Short Physical Performance Battery, Life Space Assessment, walking while talking test, and Activities-specific Balance Confidence scale.

RESULTS

Seventy-two community-dwelling lower limb prosthesis users were enrolled. The sample included 62 male participants (86%), and 58 participants (81%) had transtibial amputation. The average age of participants was 65 (8.9) years, and for 49 participants (70%), the amputation was over 24 months ago. The total mean Standard Deviation (SD) Physical Activity Scale for the Elderly score was 153.2 (88.3), with scores of 148.1 (11.4) and 184.5 (24.7) for male and female participants, respectively. Regression analysis identified Life Space Assessment (β = 1.15, p = 0.007) and Short Physical Performance Battery (β = 3.51, p = 0.043) as statistically significant predictors accounting for 25% of the variance in PA.

CONCLUSIONS

Community mobility and physical performance are the most meaningful predictors of PA. Future research should examine additional factors (e.g., environment, motivation). Understanding the predictors for PA after LLL would improve clinical practice as clinicians would have increased knowledge to modify and improve training.

The relationship of hip strength to walking and balance performance in unilateral lower limb prosthesis users differs by amputation level

BACKGROUND

Safe and efficient locomotion is a frequently stated goal of lower limb prosthesis users, for which hip strength may play a central yet poorly understood role. Additional research to identify associations between hip strength, balance, and mobility among transtibial and transfemoral prosthesis users is required.

OBJECTIVE

To test whether residual and/or intact limb isometric hip strength was associated with lower limb prosthesis users' walking speed, endurance, and balance.

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

PARTICIPANTS

Convivence sample of 14 transtibial and 14 transfemoral prosthesis users.

METHODS

Multiple linear regression was used to evaluate the relationship between isometric measures of residual and intact limb hip strength and walking and balance performance.

MAIN OUTCOME MEASUREMENTS

Measures of isometric hip muscle strength, including peak torque, average torque, torque impulse, and torque steadiness (i.e. consistency with which an isometric torque can be sustained) were derived from maximum voluntary hip flexion, extension, abduction and adduction torque signals collected with a motor-driven dynamometer. Walking speed, endurance, and balance were assessed by administering the 10-meter walk test, 2-minute walk test, Four Square Step Test, and Narrowing Beam Walking Test, respectively.

RESULTS

Residual limb hip extensor max torque and abductor torque steadiness explained between 51% and 69% of the variance in transtibial prosthesis users' walking speed, endurance, and balance. In contrast, intact limb hip abductor torque impulse explained between 33% and 48% of the variance in transfemoral prosthesis users' walking speed, endurance, and balance.

CONCLUSIONS

Our results suggest that unilateral transtibial and transfemoral prosthesis users' walking and balance performance may depend on different hip muscles, and different facets of hip strength. Amputation level-specific hip strength interventions may therefore be required to improve walking and balance performance in unilateral transtibial and transfemoral prosthesis users. The "intact leg strategy" adopted by transfemoral prosthesis users may be due to a variety of prosthesis and biomechanical factors that limit the efficiency with which transfemoral prosthesis users can exploit the strength of their residual limb hip muscles while walking.

Benefits and durability of an affordable prosthetic silicone cushion liner locally manufactured in a resource-limited environment: Enabling adoption of total surface bearing sockets and silicone cushion liners

INTRODUCTION

Prosthetic silicone liners improve comfort and skin protection and allow the use of total surface bearing (TSB) sockets, which provide enhanced proprioception and comfort. Unfortunately, silicone liners are cost-prohibitive in resource-limited environments (RLEs) where patellar tendon bearing (PTB) sockets with PE-lite liners remain standard, leading to patient discomfort and skin issues.

OBJECTIVE

This study evaluates the benefits and durability of an affordable silicone liner locally manufactured in an RLE to promote TSB socket adoption, aiming to enhance prosthetic care and patient outcomes.

METHODS

Ethical approval was granted by the Nepal Health Research Council. Twelve people with a unilateral transtibial amputation who were using a PTB socket with PE-lite participated in the study and received a new prosthesis (TSB socket with an affordable silicone liner). Participants performed mobility tests (2-Minute Walking Test, Timed Up and Go Test) and completed self-reported questionnaires for both prostheses. Liner durability was assessed.

RESULTS

Participant mobility improved while wearing the TSB socket and silicone liner. The new prosthesis was found to be comfortable, and there were no major problems identified although excessive sweating, typical with silicone liners, was reported. Liners were replaced after 6.1 (±3.1) months.

CONCLUSION

A locally manufactured liner provided increased mobility and high levels of satisfaction. This affordable liner may be suitable for use in RLEs, enabling adoption of TSB sockets and improving rehabilitation outcomes of people with a transtibial amputation. However, durability concerns and excessive sweating would suggest that improvements can still be made.

Assessing walking speed in persons with a lower-limb amputation: Test-retest reliability of the 10-m walk test

BACKGROUND

Preferred walking speed (PWS), maximal walking speed (MWS), and walking speed reserve (WSR)-the difference between MWS and PWS-can be easily obtained from the 10-m walk test (10MWT) to assess walking ability and function. However, their test-retest reliability has not been determined in persons with unilateral lower-limb amputation (LLA).

OBJECTIVES

To determine the reliability of the PWS, MWS, and WSR obtained from the 10MWT in persons with LLA.

STUDY DESIGN

Test-retest with a 48- to 120-h interval between test days.

METHODS

Test-retest relative and absolute reliability was assessed by the intraclass correlation coefficient (ICC) and the %change in mean (%CM) and coefficient of variation (CV), respectively.

RESULTS

Preferred walking speed showed excellent reliability between day 1 (familiarization day) and day 2 (ICC = 0.97; %CM = -1.8; CV = 7.7) and a significant speed increase from day 2 to day 3 (ICC = 0.96; %CM = 8.5, p < 0.003; CV = 7.4). Maximal walking speed showed excellent reliability between day 1 and day 2 (ICC = 0.94; %CM = 2.9; CV = 8.3) and between day 2 and day 3 (ICC = 0.94; %CM = 1.8; CV = 8.6). Overall, WSR was poorly reliable between day 1 and day 2 (ICC = 0.65; %CM = 39.2; CV = 39.2) and between day 2 and day 3 (ICC = 0.74; %CM = 30.0; CV = 30.0).

CONCLUSIONS

Preferred walking speed obtained from a single 10MWT and MWS obtained after a 10MWT familiarization day are reliable walking speed measures for persons with LLA with similar characteristics to those of our sample. Nonetheless, it is critical that both PWS and MWS are obtained after a 10MWT familiarization to obtain a reliable WSR.

Validity and reliability of Glittre activities of daily living test in lower-limb prosthetic users

BACKGROUND

Functional capacity assessments have an important role in determining the level of mobility in lower-limb prosthetic users.

OBJECTIVES

Our aim was to investigate the reliability and validity of the Glittre activities of daily living (ADL) test in lower-limb prosthetic users.

STUDY DESIGN

A cross-sectional study.

METHODS

The study included 66 people over the age of 18 years who had used a lower-limb prosthesis for at least 6 months and could walk at least 30 m independently. For construct validity, the correlation of the Glittre ADL test with the 2-min walk test, timed up and go test, and functional reach test was examined, and Bland-Altman agreement analysis was performed. Intra-rater reliability was examined with 2 tests performed by the same physiotherapist on different days, and inter-rater reliability was examined with a test performed by a second physiotherapist on a different day.

RESULTS

The reliability of the Glittre ADL test was found to be excellent for intra-rater (intraclass correlation coefficient = 0.940, 95% confidence interval = 0.903-0.963, standard error of measurement = 26.03, minimal detectable change = 72.31) and good for inter-rater (intraclass correlation coefficient = 0.890, 95% confidence interval = 0.806-0.936, standard error of measurement = 36.80, minimal detectable change = 102.06, p < 0.001). There was a strong negative correlation between Glittre ADL test and 2-min walk test (r = -0.785), a strong positive correlation with timed up and go (r = 0.805), and a weak negative correlation with functional reach test (r = -0.266, p < 0.05). Bland-Altman plots showed 95% agreement for both validity and reliability measurements.

CONCLUSIONS

The Glittre ADL test is a valid and reliable test that can be used in the assessment of functional capacity in lower extremity prosthesis users.

Effect of serious games over conventional therapy in the rehabilitation of people with multiple sclerosis - a systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to quantify the effect of serious games over conventional therapy on upper-limb activity, balance, gait, fatigue, and cognitive functions in people with multiple sclerosis.

MATERIALS AND METHODS

Search strategies were developed for PubMed, Embase, Cochrane Library, and Scopus. Studies were selected if participants were adults with multiple sclerosis; the intervention consisted of a virtual reality serious game-based program; the control group received conventional therapy; outcomes included upper limb activity, balance, gait, fatigue, or cognitive functions; and used a randomized controlled trial design. Data were synthesized using a standardized mean difference with a random-effects model.

RESULTS

From 2532 studies, seventeen trials were selected (n = 740). Overall, serious games programs effect on upper limb activity, gait, verbal memory, verbal fluency and attention seemed neutral. Balance functions appeared to be improved by semi-immersive virtual reality serious games (SMD = 0.48;95%CI = 0.12-0.84;p = 0.01;I2=0%), fatigue by treadmill serious games (SMD = 0.80;95%CI = 0.40-1.20;p < 0.001) and visuo-spatial memory by semi-immersive virtual reality general cognitive serious games (SMD = 0.35;95%CI = 0.04-0.65;p = 0.03;I2=0%).

CONCLUSION

This review suggests, with a very-low-to-low certainty of evidence, that while some specific serious games may improve balance, fatigue and visuo-spatial memory, their overall effect on upper limb activity, gait, and other cognitive functions appears neutral.

Energy expenditure during typical household and community activities of daily living in persons with lower limb amputation: A pilot study

INTRODUCTION

Knowledge about the energy expenditure of typical activities of daily living (ADL) in persons with lower limb amputation (LLA) is lacking. This study investigated the following: (1) oxygen consumption per unit distance (V̇O 2 ; mL·kg -1 ·min -1 ), (2) proportion utilization of peak oxygen consumption (%V̇O 2 peak), (3) oxygen cost (energy cost; mL·kg -1 ·m -1 ), and (4) perceived exertion (rating of perceived exertion) of ADL in persons with LLA and able-bodied controls.

METHODS

Participants (21 with LLA/12 controls) performed 2 household ADL experiments: in-house walking and vacuuming and 3 community ADL experiments: marked shopping, fast walking, and stair negotiation. V̇O 2 peak was assessed with arm crank ergometry, and ambulatory activity was monitored for 7 days with a StepWatch.

RESULTS

Participants with LLA performed in-house walking, marked shopping, vacuuming, and stair negotiation at a similar V̇O 2 as controls, while their self-selected walking speed (WS) was significantly lower. Participants with LLA had significantly higher %V̇O 2 peak than controls during in-house walking and reported a significantly higher rating of perceived exertion for vacuuming and marked shopping. The highest possible WS of participants with LLA during fast walking was significantly lower than that of controls, but V̇O 2 was also significantly lower, indicating a limited capacity to walk at higher WS. Participants with LLA had a significantly lower daily step count, significantly lower-proportion high-intensity ambulation, but significantly higher-proportion low-intensity ambulation than controls, indicating that persons with LLA also walked at lower WS in daily life.

CONCLUSIONS

The results indicate that persons with LLA have increased physical and perceived effort during performance of ADL compared with persons without amputation, which has consequences for community participation, and hence independence and quality of life.

Tibiotalocalcaneal arthrodesis with an intramedullary nail: The functional and clinical outcome of a challenging patient group and its comparison to a below knee amputation

BACKGROUND

Tibiotalocalcaneal arthrodesis (TTCA) is a salvage procedure to fuse the ankle and subtalar joints to treat severe ankle and hindfoot disease. Patients often have multiple operations before a TTCA. A below knee amputation (BKA) has major physical and psychological impacts. Our aim is to investigate the outcomes of these treatments in salvage situations, with a focus on objective functional measurements and patient reported outcome measures (PROMs).

METHODS

52 patients underwent TTCA with a retrograde intramedullary nail and contacted for clinical and functional assessments and compared to patients who underwent traumatic BKA. PROMS such as AOFAS score, SF-36 and foot function index (FFI), and objective functional outcome measures were used.

RESULTS

Of the 52 TTCA patients, 28 patients were recruited for follow-up. 35.7% of patients had postoperative complications. Mean postoperative AOFAS score was 63.9 ± 8.4 (range, 47-81), FFI 48.8 ± 15.8 (range, 22.2-75.2). 11 BKA patients (mean age 46.4 years) were included as control group. BKA patients scored higher than the TTCA patients on SF-36 physical functioning (p < 0.01) and SF-36 mental health (p < 0.05) subscales. The flat-surface functional tests (timed up and go test, 2-minute walk test, 10-meter walk test) showed significantly (p < 0.05) better outcomes for the BKA compared to TTCA.

CONCLUSIONS

A TTCA is a salvage procedure with high complication rates. Functional and psychometric results are reduced compared to the normal population. Patients after a BKA had significantly better scores on SF-36 functional and mental health subscales and better functional outcomes for flat ground activities compared to TTCA. Heterogeneity of the TTCA and BKA patient cohorts is a limitation of this study. With these results in mind, the outlook of a BKA is not necessarily a grim one. They may be used by surgeons to counsel patients preoperatively when managing complex ankle and hindfoot disease.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The development of rating scales to evaluate experiential prosthetic foot preference for people with lower limb amputation

BACKGROUND

Selection of a foot is an important aspect of prosthetic prescription and vital to maximizing mobility and functional goals after lower limb amputation. Development of a standardized approach to soliciting user experiential preferences is needed to improve evaluation and comparison of prosthetic feet.

OBJECTIVE

To develop rating scales to assess prosthetic foot preference and to evaluate use of these scales in people with transtibial amputation after trialing different prosthetic feet.

DESIGN

Participant-blinded, repeated measures crossover trial.

SETTING

Veterans Affairs and Department of Defense Medical Centers, laboratory setting.

PARTICIPANTS

Seventy-two male prosthesis users with unilateral transtibial amputation started, and 68 participants completed this study.

INTERVENTIONS

Participants trialed three mobility-level appropriate commercial prosthetic feet briefly in the laboratory.

MAIN OUTCOME MEASURES

"Activity-specific" rating scales were developed to assess participants' ability with a given prosthetic foot to perform typical mobility activities (eg, walking at different speeds, on inclines, and stairs) and "global" scales to rate overall perceived energy required to walk, satisfaction, and willingness to regularly use the prosthetic foot. Foot preference was determined by comparing the rating scale scores, after laboratory testing.

RESULTS

The greatest within-participant differences in scores among feet were observed in the "incline" activity, where 57% ± 6% of participants reported 2+ point differences. There was a significant association (p < .05) between all "activity-specific" rating scores (except standing) and each "global" rating score.

CONCLUSIONS

The standardized rating scales developed in this study could be used to assess prosthetic foot preference in both the research and clinical settings to guide prosthetic foot prescription for people with lower limb amputation capable of a range of mobility levels.

Effects of a Powered Ankle-Foot Prosthesis and Physical Therapy on Function for Individuals With Transfemoral Limb Loss: Rationale, Design, and Protocol for a Multisite Clinical Trial

BACKGROUND

Powered ankle-foot prosthetic devices can generate net positive mechanical work during gait, which mimics the physiological ankle. However, gait deviations can persist in individuals with transfemoral limb loss because of habit or lack of rehabilitation. Prosthetic research efforts favor the design or evaluation of prosthetic componentry and rarely incorporate any type of rehabilitation, despite evidence suggesting that it is critical for minimizing gait imbalances. Given the accelerated rate of innovation in prosthetics, there is a fundamental knowledge gap concerning how individuals with transfemoral limb loss should learn to correctly use powered ankle-foot devices for maximum functional benefit. Because of the recent advances in prosthetic technology, there is also a critical unmet need to develop guidelines for the prescription of advanced prosthetic devices that incorporate both physical and psychological components to identify appropriate candidates for advanced technology.

OBJECTIVE

The primary goal of this investigation is to examine the roles of advanced prosthetic technology and a device-specific rehabilitative intervention on gait biomechanics, functional efficacy, and pain in individuals with transfemoral limb loss. The secondary goal is to develop preliminary rehabilitation guidelines for advanced lower limb prosthetic devices to minimize gait imbalances and maximize function and to establish preliminary guidelines for powered ankle-foot prosthetic prescription.

METHODS

This prospective, multisite study will enroll 30 individuals with unilateral transfemoral limb loss. At baseline, participants will undergo a full gait analysis and assessment of function, neurocognition, cognitive load, subjective preferences, and pain using their current passive prosthesis. The participants will then be fitted with a powered ankle-foot device and randomized into 2 equal groups: a powered device with a device-specific rehabilitation intervention (group A) or a powered device with the current standard of practice (group B). Group A will undergo 4 weeks of device-specific rehabilitation. Group B will receive the current standard of practice, which includes basic device education but no further device-specific rehabilitation. Data collection procedures will then be repeated after 4 weeks and 8 weeks of powered ankle use.

RESULTS

This study was funded in September 2017. Enrollment began in September 2018. Data collection will conclude by March 2024. The initial dissemination of results is expected in August 2024.

CONCLUSIONS

The projected trends indicate that the number of individuals with limb loss will dramatically increase in the United States. The absence of effective, evidence-based interventions may make individuals with transfemoral limb loss more susceptible to increased secondary physical conditions and degenerative changes. With this expected growth, considerable resources will be required for prosthetic and rehabilitation services. Identifying potential mechanisms for correcting gait asymmetries, either through advanced prosthetic technology or rehabilitative interventions, can provide a benchmark for understanding the optimal treatment strategies for individuals with transfemoral limb loss.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03625921; https://clinicaltrials.gov/study/NCT03625921.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/53412.

Accuracy of wrist-worn activity trackers for measuring steps in patients after major abdominal surgery: A validation study

Background

Wearable activity trackers provide a simple and objective measurement of postoperative mobilization. However, few have validated the accuracy of trackers in patients after major abdominal surgery.

Objective

To examine the accuracy of wrist-worn activity trackers to measure steps of patients in early mobilization after major abdominal surgery, and to explore the influence of clinical variables and gait parameters on the accuracy of trackers.

Methods

Forty-five patients after major abdominal surgery were recruited to participate in modified six-minute walk tests wearing three trackers simultaneously, the Fitbit Inspire HR, Xiaomi MI 4, and HONOR 5. The differences in displayed steps before and after the walking test were considered as the step counts measured by the trackers; the actual steps taken were determined as the average of the values manually counted by two researchers. The intraclass correlation coefficient, Bland-Altman method, mean percentage error, and mean absolute percentage error were used to assess the accuracy of trackers with reference to manual step counts.

Results

The three trackers undercounted postoperative steps by -65.5% to -23.5%. Analysis showed low-to-good agreement between step counts recorded by trackers and actual steps (ICC = 0.35-0.75); the mean absolute percentage errors ranged from 24.5% to 65.7%. For all trackers, mean absolute percentage errors correlated negatively with postoperative days (r = -0.626 to -0.744), walking speed (r = -0.714 to -0.854), step length (r = -0.466 to -0.615), and cadence (r = -0.681 to -0.790), while there were positive correlations between mean absolute percentage errors and the number of abdominal drains (r = 0.450-0.514).

Conclusions

The specific activity trackers used in this study might not be reliable tools for measuring steps counts during the walking test in the early postoperative period for patients undergoing major abdominal surgery.

Interventions for motor rehabilitation in people with transtibial amputation due to peripheral arterial disease or diabetes

BACKGROUND

Amputation is described as the removal of an external part of the body by trauma, medical illness or surgery. Amputations caused by vascular diseases (dysvascular amputations) are increasingly frequent, commonly due to peripheral arterial disease (PAD), associated with an ageing population, and increased incidence of diabetes and atherosclerotic disease. Interventions for motor rehabilitation might work as a precursor to enhance the rehabilitation process and prosthetic use. Effective rehabilitation can improve mobility, allow people to take up activities again with minimum functional loss and may enhance the quality of life (QoL). Strength training is a commonly used technique for motor rehabilitation following transtibial (below-knee) amputation, aiming to increase muscular strength. Other interventions such as motor imaging (MI), virtual environments (VEs) and proprioceptive neuromuscular facilitation (PNF) may improve the rehabilitation process and, if these interventions can be performed at home, the overall expense of the rehabilitation process may decrease. Due to the increased prevalence, economic impact and long-term rehabilitation process in people with dysvascular amputations, a review investigating the effectiveness of motor rehabilitation interventions in people with dysvascular transtibial amputations is warranted.

OBJECTIVES

To evaluate the benefits and harms of interventions for motor rehabilitation in people with transtibial (below-knee) amputations resulting from peripheral arterial disease or diabetes (dysvascular causes).

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 9 January 2023.

SELECTION CRITERIA

We included randomised controlled trials (RCT) in people with transtibial amputations resulting from PAD or diabetes (dysvascular causes) comparing interventions for motor rehabilitation such as strength training (including gait training), MI, VEs and PNF against each other.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. prosthesis use, and 2.

ADVERSE EVENTS

Our secondary outcomes were 3. mortality, 4. QoL, 5. mobility assessment and 6. phantom limb pain. We use GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We included two RCTs with a combined total of 30 participants. One study evaluated MI combined with physical practice of walking versus physical practice of walking alone. One study compared two different gait training protocols. The two studies recruited people who already used prosthesis; therefore, we could not assess prosthesis use. The studies did not report mortality, QoL or phantom limb pain. There was a lack of blinding of participants and imprecision as a result of the small number of participants, which downgraded the certainty of the evidence. We identified no studies that compared VE or PNF with usual care or with each other. MI combined with physical practice of walking versus physical practice of walking (one RCT, eight participants) showed very low-certainty evidence of no difference in mobility assessment assessed using walking speed, step length, asymmetry of step length, asymmetry of the mean amount of support on the prosthetic side and on the non-amputee side and Timed Up-and-Go test. The study did not assess adverse events. One study compared two different gait training protocols (one RCT, 22 participants). The study used change scores to evaluate if the different gait training strategies led to a difference in improvement between baseline (day three) and post-intervention (day 10). There were no clear differences using velocity, Berg Balance Scale (BBS) or Amputee Mobility Predictor with PROsthesis (AMPPRO) in training approaches in functional outcome (very low-certainty evidence). There was very low-certainty evidence of little or no difference in adverse events comparing the two different gait training protocols.

AUTHORS' CONCLUSIONS

Overall, there is a paucity of research in the field of motor rehabilitation in dysvascular amputation. We identified very low-certainty evidence that gait training protocols showed little or no difference between the groups in mobility assessments and adverse events. MI combined with physical practice of walking versus physical practice of walking alone showed no clear difference in mobility assessment (very low-certainty evidence). The included studies did not report mortality, QoL, and phantom limb pain, and evaluated participants already using prosthesis, precluding the evaluation of prosthesis use. Due to the very low-certainty evidence available based on only two small trials, it remains unclear whether these interventions have an effect on the prosthesis use, adverse events, mobility assessment, mortality, QoL and phantom limb pain. Further well-designed studies that address interventions for motor rehabilitation in dysvascular transtibial amputation may be important to clarify this uncertainty.

Use of Physical Activity Measures in Rehabilitation Interventions Following Lower Extremity Amputation

Purpose of Review

This systematic review aims to evaluate physical performance outcome tools that are used most frequently to assess rehabilitation interventions. The scope of this paper focused on outcomes used with established lower limb amputees when assessing interventions such as exercise programs or changes in prescription published in the last 5 years.

Recent Findings

The most recorded outcome measures used across all the papers were timed walk tests and the Activity Balance Confidence Scale. Many outcomes did not produce statistically significant results with established amputee cohorts. Understanding the minimal important clinical difference is key.

Summary

The use of outcome measures is essential. Training and education are likely to increase the use of outcome measures. Quality of life measures are important in conjunction with physical outcomes. Simple timed walk tests are commonly used. These are in general easy to administer requiring a small space, limited equipment, and a short time frame.

Amputation and prosthetics of the lower extremity: The 2020 Dutch evidence-based multidisciplinary guideline

BACKGROUND

Lower-limb amputations are rare but debilitating events in the lives of affected persons. Treatment of persons with amputation inherently involves many different health care professions at different stages leading to and after an amputation. There are prevailing clinical questions within the work field related to different facets of care including peri/postoperative aspects, prosthetic components, rehabilitation treatment, and health care processes.

OBJECTIVES

To provide an up-to-date multidisciplinary evidence-based guideline for health care professionals involved in the treatment of persons with lower-limb amputation in the Netherlands.

METHODS

Identification of key questions in a focus group, systematic review of the evidence (up to March 2019, using Embase and MEDLINE databases), and weighing considerations, culminating in clinical recommendations.

RESULTS

Twelve key questions were formulated. Recommendations of two key questions were upheld in line with the previous 2012 guideline. Ten systematic literature searches were performed, leading to the inclusion of 59 studies.

CONCLUSION

A summary of evidence-based conclusions, considerations, and recommendations of the 2020 guideline is presented.

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.

Performance of timed function tests as outcome measures in idiopathic inflammatory myopathy-results from a single-centre cohort

OBJECTIVE

To evaluate performance of timed function tests (TFTs) in assessing muscle strength and endurance as determined by Manual Muscle Testing 8 (MMT-8) and Functional Index 2 (FI-2), respectively, in idiopathic inflammatory myopathies (IIM).

METHODS

This cohort study included 42 IIM patients satisfying 2017 EULAR/ACR criteria. Patients were classified as active (n = 18) or inactive disease (n = 24) based on clinical status at baseline. MMT-8, FI-2, 30 s rise from chair test, 30 s 1 kg arm rise test and 2-min walking distance (2MWD) were administered at baseline, 3 months and 6 months. Pearson rank correlation analysis and receiver operating curves were performed to assess the performance of timed function tests.

RESULTS

All patients were followed up at 3 months and 39 completed 6 months' follow-up. All the three TFTs had excellent convergent (r > 0.7, P < 0.05) and divergent validity (P < 0.05). Only 2MWD had moderate to strong correlation with ΔMMT-8 at 3 and 6 months among those with active disease (P = 0.001). All the TFTs correlated with ΔFI-2 in active disease but only Δ2MWD correlated with ΔFI-2 in inactive disease at 6 months (r = 0.506, P = 0.036). At a cut-off of 5% improvement in MMT-8, 2MWD had an area under the curve (AUC) of 0.868 with 95% sensitivity with 2% improvement at 3 months. To detect a 10% ΔMMT-8, Δ2MWD at a cut of 8% and 7% had an AUC of 0.909 and 0.893 with a sensitivity of 92% at 3 and 6 months, respectively (P < 0.05).

CONCLUSION

2MWD is a reliable indicator of muscle strength, endurance and treatment response. The 2MWD can be self-administered by patients, making it a potential patient-reported outcome measure.

Walking asymmetry and its relation to patient-reported and performance-based outcome measures in individuals with unilateral lower limb loss

Gait asymmetry persists for most people after lower limb amputation and is associated with slower walking speeds. However, the relationship between gait asymmetry and patient-reported function remains unclear because they are not commonly assessed together. The purpose of this study was to determine relationships between gait asymmetries in people with lower limb loss and (1) patient-reported outcomes and (2) performance-based prosthetic functional measures. This cross-sectional analysis included nine people with unilateral limb loss aged 48.2 ± 13.1 years of mixed amputation etiology. Patient-reported outcomes included the Prosthetic Evaluation Questionnaire mobility subscale and Activities-specific Balance Confidence scale. Performance outcomes included the Berg Balance Scale and the 30-second sit-to-stand test. Walking performance measures included the 2-Minute Walk Test, during which APDM Opal sensors recorded spatiotemporal gait parameters, and daily step-counts from StepWatch4 activity monitors. The study found that the most asymmetric gait symmetry ratios (prosthetic-limb divided by intact-limb) could be attributed to prosthetic foot dorsiflexion-plantarflexion and rotation motion limitations: prosthetic-limb trailing double support (0.789 ± 0.052), toe-off (0.760 ± 0.068) and toe-out angle (0.653 ± 0.256). Single limb stance, and stance and swing phase durations were most strongly associated with balance and walking performance measures. Notably, no symmetry ratio was significantly associated with patient-reported prosthetic function (unadjusted Pearson correlation coefficients r < 0.50, P > 0.05). More gait symmetry was associated with better balance and walking performance but had no significant relationship with patient-reported function. Although achieving gait symmetry after lower limb loss is a common walking goal, symmetry was unrelated to the perception of functional mobility for people with lower limb loss.

Telehealth interventions for mobility after lower limb loss: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Mobility is a crucial component for healthy aging after lower limb loss (LLL). Telehealth technologies, for example, smart devices, are novel approaches for health programs delivery regardless of geographical boundaries.

OBJECTIVES

To assess the effect of telehealth interventions on mobility, quality of life, and antecedents of health behavior compared with a control condition (usual care or simpler telehealth interventions with fewer number of behavior change techniques [BCTs]) for community-dwelling adults (>50 years) with an LLL and the effect of mode of delivery and BCTs used in telehealth interventions on health outcomes.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

We systematically searched MEDLINE, PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane, PsycINFO, and SPORTDiscus on January 28, 2021, to identify relevant randomized controlled trials. Two authors independently screened records and assessed risk of bias. We conducted a narrative synthesis of evidence and, when appropriate, used the standardized mean difference (SMD) and mean difference for meta-analyses and the Grading Recommendations Assessment, Development, and Evaluation approach for practice recommendations.

RESULTS

We identified six randomized controlled trials. Telephone was the most common delivery mode (n = 3), and "instructions for performing behaviors" was the most common BCT (n = 5). Very low certainty evidence showed no changes in mobility (six studies: SMD = 0.33 [95% confidence interval [CI] = -0.08, 0.75]), quality of life (two studies: mean difference = -0.08 [95% CI = -0.30, 0.15]), and antecedents of behavior (five studies: SMD = 0.04 [95% CI = -0.28, 0.36]).

CONCLUSIONS

Our review highlights a knowledge gap for the effect of telehealth interventions for people with LLL. Although no promising effect was shown for telehealth interventions, very low certainty evidence precludes making a definitive clinical recommendation.

Variations in 2-Minute Walk Test outcomes for people with lower limb amputation in the outpatient clinic and research settings

BACKGROUND

This study determined the differences in 2-Minute Walk Test (2MWT) distances between people with lower limb amputations in clinical and research settings and described variations in test administration in various clinical settings.

STUDY DESIGN

Retrospective Cross-sectional design.

METHODS

The 2MWT for 290 patients with lower limb amputations were obtained from a medium-sized prosthetic company with locations within the central United States. Data on 12 prosthetists' 2MWT administration decisions were obtained from the results of an administrative questionnaire. Patient 2MWT distances were compared with published distances. Multiple regression was used to examine the impact of test settings on 2MWT outcomes. Descriptive statistics were used to present prosthetists' variations in test administration.

RESULTS

Clinical 2MWT distances were significantly less than distances obtained in a research setting. Clinical facilities reported inconsistent path dimensions and potential obstacles in proximity to the test area. Variations in test administration by prosthetists with respect to path length, instructions, turn marker, and overage measurement may contribute to the differences.

CONCLUSIONS

Prosthetists should be aware that comparisons of patients' 2MWT distance in a clinical environment may differ from published results. Although variations in clinical environments are usually nonmodifiable characteristics of the clinical facility, test administration and scoring could be modified.

A Comparison of the Two-Minute Walk Test and Comprehensive High-level Activity Mobility Predictor (CHAMP) in People with a Leg Prosthesis

OBJECTIVE

To determine if the two-minute walk test (2MWT) could serve as an alternative measure of high-level mobility in lower limb prosthesis users when circumstances preclude administration of the Comprehensive High-level Activity Mobility Predictor (CHAMP).

DESIGN

Cross-sectional study.

SETTING

Indoor recreational athletic field and gymnasium.

SUBJECTS

Fifty-eight adult lower limb prosthesis users with unilateral or bilateral lower limb amputation who participate in recreational athletic activities.

INTERVENTION

N/A.

MAIN MEASURES

The 2MWT and CHAMP while using their preferred prosthesis(es) on an indoor artificial athletic field or hardwood gymnasium floor.

RESULTS

Thirty-nine men and nineteen women with a median age of 38.3 years participated in the study. Most participants experienced amputation(s) due to trauma (62%) or tumor (10%) and were generally higher functioning (K4 (91.4%) and K3 (8.6%)). The median (range) score for the CHAMP was 23.0 points (1.5-33.5) and the mean ± standard deviation (range) 2MWT distance walked was 188.6 ± 33.9 m (100.2-254.3 m). The CHAMP demonstrated a strong positive relationship with 2MWT (r = 0.83, p < 0.001). The 2MWT distance predicted 70% of the variance in CHAMP score.

CONCLUSIONS

Although the 2MWT does not test multi-directional agility like the CHAMP, they were found to be highly correlated. If space is limited, the two-minute walk test can serve as an alternative measure for assessing high-level mobility capabilities in lower limb prosthesis users.

Exploring the interaction of knee and ankle component use on mobility test performance in people with unilateral transfemoral amputation

BACKGROUND

Ankle-foot and knee components are important determinants of mobility for individuals with transfemoral amputation. Individually, advanced ankle-foot and knee components have been shown to benefit mobility in this group of people. However, it is not clear what effect a variety of combinations of ankle-foot and knee components have on mobility test performance.

OBJECTIVES

To assess whether outcomes from mobility tests in people with unilateral transfemoral amputation are influenced by varying combinations of ankle-foot and knee components.

STUDY DESIGNS

Repeated measures.

METHODS

Nine adults with unilateral transfemoral amputation completed the two-minute walk test, the timed up-and-go test, the L-test, and a custom locomotion course in four randomized prosthetic conditions. These conditions were each a combination of an ankle-foot component (rigid, nonarticulating [RIG] or hydraulically articulating [HYD]) and a knee component (non-microprocessor-controlled [NMPK] or microprocessor-controlled [MPK]). The test-retest reliability and concurrent validity of the custom locomotion course were also established.

RESULTS

The best performance in all mobility tests was associated with the MPK + HYD combination, followed by the MPK + RIG, NMPK + HYD, and NMPK + RIG combinations. This effect was statistically significant for the two-minute walk test (P = 0.01, = 0.36) and on threshold for the L-test (P = 0.05, = 0.36), but not statistically significant for the locomotion course (P = 0.07, = 0.38) or the timed up-and-go test (P = 0.12, = 0.22). Locomotion course performance had good to excellent test-retest reliability and strong concurrent validity.

CONCLUSION

Using a combination of a HYD ankle-foot and a MPK knee resulted in the highest performance in mobility tests. This was observed in contrast to combinations of prosthetic components that included a rigid ankle-foot component and/or a NMPK knee component.

Functional outcomes and user preferences of individuals with transfemoral amputations using two types of knee joints in under-resourced settings

BACKGROUND

Information relating to prosthetic performance can inform clinical practice and improve patient outcomes in under-resourced countries.

OBJECTIVES

The main goal of this study was to compare functional outcomes and user preferences of individuals with transfemoral amputations using common types of knee joints in an under-resourced country.

STUDY DESIGN

Prospective, longitudinal, before and after trial.

METHODS

Twenty individuals with unilateral transfemoral amputations from a center in Cambodia transitioned from a commonly used single-axis manually locking knee International Committee of the Red Cross (ICRC) to a more advanced multiaxis knee joint with stance control All-Terrain Knee (ATK). Data were collected for the ICRC knee joint and the ATK immediately after fitting, after acclimation, and as part of a long-term follow-up. A timed walk test assessed walking distance and efficiency. Mobility and user-preferences were evaluated through questionnaires.

RESULTS

Distance during the timed walk test was significantly higher for the ATK compared with ICRC (P < 0.001), with functional gains retained at follow-up. No differences were found for gait efficiency and the mobility questionnaires. All participants, except one, preferred the ATK prosthesis. Benefits included greater knee stability and fewer perceived knee collapses; however, some disliked the appearance of the ATK.

CONCLUSIONS

The findings suggest positive outcomes with prosthetic services in under-resourced regions and the ICRC system, as well as the potential for improved functional outcomes with more advanced multiaxis knee components.

Group-based telerehabilitation intervention using Wii Fit to improve walking in older adults with lower limb amputation (WiiNWalk): A randomized control trial

OBJECTIVE

Determine efficacy of the novel WiiNWalk intervention on walking-related outcomes in older adults with lower limb amputation.

DESIGN

Multi-site, parallel, evaluator-masked randomized controlled trial.

SETTING

Home-setting in three Canadian cities.

PARTICIPANTS

Community-dwelling lower limb prosthesis users over 50 years of age.

INTERVENTIONS

The WiiNWalk group (n = 38) used modified Wii Fit activities for prosthetic rehabilitation. The attention control group (n = 33) used Big Brain Academy: Wii Degree, comprising of cognitive activities. Both groups completed a 4-week supervised phase with three 1-h sessions/week in groups of three overseen by a clinician via videoconferencing and a 4-week unstructured and unsupervised phase.

MAIN MEASURES

Primary outcome was walking capacity (2 min walk test); secondary outcomes were balance confidence (activities-specific balance confidence scale), dynamic balance (four-step square test), and lower limb functioning (short physical performance battery). Outcomes were compared across time points with repeated measures analysis of covariance, adjusting for baseline and age.

RESULTS

Mean age was 65.0 (8.4) years, with 179.5 (223.5) months post-amputation and 80% transtibial amputation. No group difference in a 2 min walk test with an effect size: 1.53 95% CI [-3.17, 6.23] m. Activities balance confidence was greater in the WiiNWalk group by 5.53 [2.53, 8.52]%. No group difference in the four-step square test -0.16 [-1.25, 0.92] s, nor short physical performance battery 0.48 [-0.65, 1.61]. A post-hoc analysis showed the greatest difference in balance confidence immediately after an unsupervised phase.

CONCLUSIONS

The WiiNWalk intervention improved balance confidence, but not walking-related physical function in older adult lower limb prosthesis users. Future rehabilitation games should be specific to the amputation context.Clinical Trial Registration number, NCT01942798.

Validity of measures for life space mobility and physical activity in older adults with lower-limb amputation

BACKGROUND

Older adults with lower-limb amputations (LLAs) often experience lack of confidence and poor balance, which limits their mobility. There are few validated measures for assessing these outcomes in the LLA population.

OBJECTIVES

To assess the validity of the Life Space Assessment (LSA) and the Physical Activity Scale for the Elderly (PASE) for older adults with LLA.

STUDY DESIGN

Secondary analyses of cross-sectional data.

METHODS

Sixty-eight older adults with LLA across Canada were recruited to complete the LSA and the PASE. Validity was assessed via correlations with the Activities-specific Balance Confidence (ABC), Four-Square Step Test (FSST), and Two-Minute Walk Test (2-MWT).

RESULTS

As hypothesized, the LSA was positively correlated with the ABC (ρ = 0.36, 95% confidence interval [CI] [0.17, 0.62]) and 2-MWT (r = 0.49, 95% CI [0.27, 0.70]) and negatively correlated with FSST (ρ = -0.39, 95% CI [-0.56, -0.10]). The PASE was positively correlated with the ABC (ρ = 0.34, 95% CI [0.10, 0.56]) and 2-MWT (ρ = 0.32, 95% CI [0.05, 0.52]), and negatively correlated with FSST (ρ = -0.36, 95% CI [-0.53, -0.07]).

CONCLUSIONS

The LSA has validity in measuring life space mobility. The PASE captures the physical activity with weaker support of validity in older adults with LLA.

CLINICAL RELEVANCE

The LSA and PASE are quick low-cost tools for clinicians to assess mobility-related functional health and physical activity, respectively, in older adults with LLA. However, the PASE may contain activities that are not common among older adults with LLA.

Validade de construto do teste de caminhada de 2 minutos para pacientes com amputação de membro inferior protetizados

RESUMO Aliados da avaliação funcional, os testes de caminhada têm sido considerados confiáveis e válidos para várias populações, quantificando a capacidade funcional do indivíduo e respondendo a mudanças durante o processo de reabilitação. O objetivo deste artigo foi analisar a validade de construto do teste de caminhada de 2 minutos para pacientes com amputação de membro inferior protetizados, submetidos à reabilitação. Foi aplicado o teste de caminhada de 2 minutos em 51 pacientes maiores de 18 anos com diagnóstico clínico de amputação de membro inferior em qualquer nível e que tivessem sido submetidos à reabilitação há pelo menos seis meses no momento da avaliação, que foi correlacionada com os questionários Medida Funcional para Amputados (MFA) e os aspectos do Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), a fim de obter o coeficiente de correlação de Pearson com o nível de significância de p<0,05. Entre os participantes do estudo, 64,7% eram do sexo masculino, com média de idade de 53,4 anos; 59,92% tinham amputação de nível transtibial e a principal causa foi trauma, com 54,9%. O escore médio para os questionários foi de 63,58 pontos para a capacidade física do SF-36, e 37,14 pontos para a segunda questão do MFA. A correlação da distância percorrida no teste de caminhada de 2 minutos mostrou moderada correlação com a capacidade física do SF-36 e com a segunda questão do MFA. Os achados mostram moderada correlação entre o teste de caminhada de 2 minutos e as ferramentas subjetivas de avaliação de função utilizadas, mostrando que é um instrumento válido como medida objetiva para a população estudada.

Relationship between level of daily activity and upper-body aerobic capacity in adults with a lower limb amputation

BACKGROUND

Previous studies show that people with lower limb amputation (LLA) have a sedentary lifestyle, reduced walking capacity, and low cardiorespiratory fitness (VO2peak). There is, however, no knowledge on the relationship between cardiorespiratory fitness and objectively measured level of physical activity in daily life.

OBJECTIVES

To investigate the relationship between upper-body VO2peak, physical activity levels, and walking capacity in persons with LLA.

STUDY DESIGN

Correlational and descriptive study.

METHODS

Fourteen participants with LLA performed an assessment of VO2peak on an arm-crank ergometer and walking capacity (preferred walking speed and 2-minute walking test). Level of physical activity was measured over 7 days with a step activity monitor (number of steps; sedentary time; and proportion of low-intensity, moderate-intensity, high-intensity, and peak-intensity activity level).

RESULTS

VO2peak correlated significantly with number of steps per day (r = 0.696, p = 0.006), sedentary time (r = -0.618, p = 0.019), high-intensity activity level (r = 0.769, p = 0.001), and peak-intensity activity level (r = 0.674, p = 0.008). After correcting for age, correlations were still large and significant. Large correlations were also found between VO2peak, preferred walking speed (r = 0.586, p = 0.027), and 2-minute walking test (r = 0.649, p = 0.012).

CONCLUSIONS

We provide the first evidence of the strong relationships between upper-body VO2peak, sedentary behavior, high-intensity activity level, and walking capacity in persons with LLA. Further research is needed to investigate the potential effect of upper-body cardiorespiratory fitness on the level of activity in daily life, or vice versa.

[Correlation among tests and functional assessment scales in the follow-up of prosthetic adaptation in people with lower limb amputation]

INTRODUCTION

There is a wide variety of functional tests and scales for the assessment of different aspects in the adaptation of amputees, but there is still no consensus on which are the most appropriate.

OBJECTIVES

To describe the measures of correlation and association among three functional tests for lower-limb amputees and to define the most appropriate for this assessment. To assess general satisfaction in lower-limb prostheses users and its association with the functional tests.

METHODS

We included 83 unilateral lower-limb amputees who were users of low-cost exoskeletal prostheses. The instruments employed were the Houghton scale, the Prosthesis Evaluation Questionnaire - Mobility Scale (PEQ-MS) and the 2-minute walk test (2MWT). The statistical analysis was performed using the chi-square test and Spearman's correlation coefficient.

RESULTS

The functional tests evaluated had an acceptable correlation and association with each other, but the Spearman correlation between the Houghton scale and the 2MWT was of greater significance (whole sample: r=0.56; below-knee amputees: r=0.53). The association measures did not achieve statistically significant results for above-knee amputees or for general satisfaction.

CONCLUSIONS

The Houghton Scale and the 2MWT showed a good correlation and association with each other, becoming possible first-line instruments for the follow-up of exoskeletal lower limb prosthesis users. No significant association was identified between satisfaction and the instruments measured.

Focusing research efforts on the unique needs of women prosthesis users

Introduction

Women with lower limb loss represent a relevant and growing patient cohort with unique rehabilitation needs. These needs are emphasized in a growing body of literature and the most recent Veteran Affairs/Department of Defense clinical practice guidelines.

Prosthetics Challenges

Women with limb loss experience greater dissatisfaction with prosthetic fit, appearance, and types of footwear they can use. There is a lack of prosthetics solutions to accommodate the desire of women to wear different footwear varieties, including high heels. The choice to wear a variety of footwear is important to attire and hence community participation. Despite these recognized challenges, women are still underserved in prosthetics research, which limits available information to guide the rehabilitation process.

Research Initiatives

This narrative review describes considerations of lower limb prosthesis prescription and use by women, and examples of current research to address these topics. Research efforts are beginning to explore factors that contribute to prosthetics prescription for women, and design creative prosthetics solutions to expand the range of available footwear options. Research is still needed to characterize the types of footwear women with limb loss prefer to use, and the effects of prosthesis designs, footwear, and lower limb loss on women mobility outcomes and community participation.

Conclusions

Through targeted research initiatives, scientists and clinicians can be responsive to the specific needs of women to provide evidence-based guidelines for prosthetics prescription and improve the patient-centered care after limb loss.

Patterns of Sitting, Standing, and Stepping After Lower Limb Amputation

OBJECTIVE

The objectives of this study were to describe sitting, standing, and stepping patterns for people with lower limb amputation (LLA) and to compare sitting, standing, and stepping between people with dysvascular LLA and people with traumatic LLA.

METHODS

Participants with dysvascular or traumatic LLA were included if their most recent LLA was at least 1 year earlier, they were ambulating independently with a prosthesis, and they were between 45 and 88 years old. Sitting, standing, and stepping were measured using accelerometry. Daily sitting, standing, and stepping times were expressed as percentages of waking time. Time spent in bouts of specified durations of sitting (<30, 30-60, 60-90, and >90 minutes), standing (0-1, 1-5, and >5 minutes), and stepping (0-1, 1-5, and >5 minutes) was also calculated.

RESULTS

Participants (N = 32; mean age = 62.6 [SD = 7.8] years; 84% men; 53% with dysvascular LLA) spent most of the day sitting (median = 77% [quartile 1 {Q1}-quartile 3 {Q3} = 67%-84%]), followed by standing (median = 16% [Q1-Q3 = 12%-27%]) and stepping (median = 6% [Q1-Q3 = 4%-9%]). One-quarter (median = 25% [Q1-Q3 = 16%-38%]) of sitting was accumulated in bouts of >90 minutes, and most standing and stepping was accrued in bouts of <1 minute (standing: median = 42% [Q1-Q3 = 34%-54%]; stepping: median = 98% [Q1-Q3 = 95%-99%]). Between-etiology differences included proportion of time sitting (traumatic: median = 70% [Q1-Q3 = 59%-78%]; dysvascular: median = 79% [Q1-Q3 = 73%-86%]) and standing (traumatic: median = 23% [Q1-Q3 = 16%-32%]; dysvascular: median = 15% [Q1-Q3 = 11%-20%]).

CONCLUSION

Participants had high daily volumes of long durations of sitting. Further, these individuals accumulated most physical activity in bouts of <1 minute.

IMPACT

High levels of sedentary behavior and physical inactivity patterns may place people with LLA at greater mortality risk relative to the general population. Interventions to minimize sedentary behaviors and increase physical activity are potential strategies for improving poor outcomes of physical therapy after LLA.

Characterizing Practice Effects in Performance-Based Tests Administered to Users of Unilateral Lower Limb Prostheses: A Preliminary Study

BACKGROUND

Performance-based tests are viewed as a gold standard for measuring physical capability. Practice effects, however, may threaten their predictive, discriminative, and evaluative applications. Despite these potential consequences, practice effects have received limited attention in users of lower limb prostheses (LLP).

OBJECTIVE

To perform an initial characterization of the occurrence, time-course, and magnitude of practice effects in three performance-based tests administered to users of LLP.

DESIGN

Secondary analysis of data from a multisite repeated-measures study.

SETTING

Outpatient clinic and research laboratory.

PARTICIPANTS

Convenience sample of established ambulatory users of unilateral transtibial and transfemoral prostheses (n = 60).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Practice effects were identified as significant changes in slope of participants' cumulative trial-by-trial records. The occurrence, time-course, and magnitude of practice effects were computed for the Timed Up and Go (TUG), Four Square Step Test (FSST), and the 10-m Walk Test (10mWT).

RESULTS

Across tests, practice effects were observed in 45% to 76% of participants. The proportion of participants with practice effects (ie, occurrence) was significantly greater for the FSST than the 10mWT (P = .008). The median number of trials (ie, time-course) required for participants to reach a consistent level of performance was not significantly different between tests (FSST: 4 trials, TUG: 4 trials; 10mWT: 3.5 trials; P = .481). Practice effect magnitude (ie, difference between the mean of trials during the plateau and best performance over the first two trials) was significantly greater than zero for the FSST (1.6 s; 16%) and TUG (1.4 s; 13%) (P < .05).

CONCLUSION

Results indicate that the FSST, TUG, and 10mWT were susceptible to practice effects in this sample of users of LLP. Practice effects may obscure significant differences in walking and balance ability, and thereby, in the absence of modifications, limit the use of these tests for making individual patient clinical decisions and analyzing group-level data.

Biobehavioral Intervention Targeting Physical Activity Behavior Change for Older Veterans after Nontraumatic Amputation: A Randomized Controlled Trial

BACKGROUND

Lower-limb amputation (LLA) due to non-traumatic vascular etiology is linked to extremely low physical activity and high disability.

OBJECTIVE

To test the feasibility of a biobehavioral intervention designed to promote physical activity.

DESIGN

A randomized, single-blind feasibility trial with a crossover design.

SETTING

Veterans Administration Medical Center.

PARTICIPANTS

Military veterans (age: 65.7 [7.8] years; mean [standard deviation]) with nontraumatic lower-limb amputation (LLA), randomized to two groups: GROUP1 (n = 16) and GROUP2 (n = 15). Both groups had similar baseline amputation characteristics (level of amputation and time since amputation).

INTERVENTIONS

Twelve weekly, 30-minute telehealth sessions of physical activity behavior-change intervention, with GROUP1 participating in weeks 1-12 and GROUP2 in weeks 13-24. GROUP1 noncontact phase in weeks 13-24 and GROUP2 attention control telehealth phase in weeks 1-12.

MAIN OUTCOME MEASURES

Feasibility (participant retention, dose goal attainment, intervention acceptability [Intrinsic Motivation Inventory [IMI] Interest and Enjoyment scale], safety) and signal of efficacy (free-living physical activity [accelerometer-based average daily step count], Late Life Function and Disability Index - Disability Scale [LLFDI-DS]).

RESULTS

Participant retention rate was high (90%), with three participants lost to follow-up during the intervention period. Dose goal attainment was low, with only 10% of participants achieving an a priori walking dose goal. Intervention was rated as acceptable, with mean IMI Interest and Enjoyment score (5.8) statistically higher than the null value of 5.0 (P = .002). There were no between-group differences in adverse event rates (falls: P = .19, lower extremity wounds: P = .60). There was no signal of efficacy for change in average daily step count (d = -0.15) or LLFDI-DS (d = -0.22 and 0.17 for frequency and limitations scales, respectively).

CONCLUSIONS

Telehealth delivered biobehavioral intervention resulted in acceptable participant retention, low dose goal attainment, high participant acceptability, and low safety risk, while having no signal of efficacy (physical activity, disability) for people with nontraumatic LLA.

The Utility of the 2-Minute Walk Test as a Measure of Mobility in People With Lower Limb Amputation

OBJECTIVES

To establish reference values for the 2-minute walk test (2-MWT) distance and gait speed in people with a lower limb amputation (LLA) who are prosthetic ambulators. Also, to describe the differences in distance and gait speed between sexes, causes of amputation, levels of amputation, health risk classification, functional levels, and age groups.

DESIGN

Cross-sectional study.

SETTING

National meeting for people with lower limb amputation.

PARTICIPANTS

A convenience sample of unilateral people (N=101; 47 men, 54 women; mean age ± SD, 50.9±14.3 y) with an LLA; 48 had a transtibial amputation and 53 had a transfemoral amputation. Participants were classified as either limited community ambulators, community ambulators, or those who exceed basic ambulation skills (K2, n=7; K3, n=70; K4, n=24).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE

2-MWT performance (ie, distance and gait speed).

RESULTS

The mean ± SD 2-MWT distance and gait speed for the entire sample was 143.8±37.5 meters (range, 49-259 m) and 72.1±18.8 meters per minute (range, 25-130 m/min), respectively. Men walked farther (distance: men, 154.2±34.2 m; women, 134.4±38.1 m) and faster (gait speed: men, 77.3±17.1 m/min; women, 67.4±19.1 m/min) than women (P<.05). The mean ± SD 2-MWT distance for K4, K3, and K2 level participants was 177.9±31.1 meters, 138.4±28.5 meters, and 81.7±26.9 meters, respectively. Functional level K4 participants performed better than K3 participants (P<.05), and K3 participants performed better than K2 participants (P<.05). People with transtibial amputation walked farther than those with transfemoral amputation (152.9±43.0 m vs 135.6±43.0 m) (P<.05). The distance and speed ambulated by those participants classified in the very high health risk group was worse than those categorized as being at an increased high health risk group (P<.05) and the no increase health risk group (P<.05). The performance of participants older than 70 years old was inferior to the performance of all younger age groups.

CONCLUSIONS

Reference values for the 2-MWT distance and gait speed were established in people with LLA who are prosthetic ambulators. Significant differences in the 2-MWT performance were found between sexes, causes of amputation, levels of amputation, health risk classification, functional levels, and age groups.

Clinical Practice Guidelines for the Rehabilitation of Lower Limb Amputation: An Update from the Department of Veterans Affairs and Department of Defense

Between 2015 and 2017, the US Department of Veterans Affairs and the US Department of Defense developed a clinical practice guideline for rehabilitation of lower limb amputation to address key clinical questions. A multidisciplinary workgroup of US Department of Veterans Affairs and US Department of Defense amputation care subject matter experts was formed, and an extensive literature search was performed which identified 3685 citations published from January 2007 to July 2016. Articles were excluded based on established review criteria resulting in 74 studies being considered as evidence addressing one or more of the identified key issues. The identified literature was evaluated and graded using the National Academies of Science GRADE criteria. Recommendations were formulated after extensive review. Eighteen recommendations were confirmed with four having strong evidence and workgroup confidence in the recommendation. Key recommendations address patient and caregiver education, consideration for the use of rigid and semirigid dressings, consideration for the use of microprocessor knees, and managed lifetime care that includes annual transdisciplinary assessments. In conclusion, this clinical practice guideline used the best available evidence from the past 10 yrs to provide key management recommendations to enhance the quality and consistency of rehabilitation care for persons with lower limb amputation.

Relevance of medical comorbidities for functional mobility in people with limb loss: retrospective explanatory models for a clinical walking measure and a patient-reported functional outcome

OBJECTIVES

Various modifiable and non-modifiable factors affect functional mobility, but subjective patient-reported and objective performance-based measures are rarely combined in explanatory analyses of functional mobility in people with limb loss. This study determined separate explanatory models for patient-reported function using the Prosthetic Evaluation Questionnaire Mobility Subscale (PEQ-MS), and performance-based 2-Minute Walk Test (2MWT).

DESIGN

Retrospective cross-sectional observational analysis.

SETTING

Wellness-walking program.

PARTICIPANTS

Three hundred five volunteers with lower limb loss participated. Sixty nine percent were men, mean age 56 (15) years. Fifty two percent had vascular amputation causes, 42% had surgical levels above the knee, and 82% had medical comorbidities. Walking levels included limited-household (21%), limited-community (30%), and independent-community (49%). Outcome measures included patient-reported PEQ-MS, Activities-specific Balance Confidence (ABC) and Houghton scales; and performance-based balance and walking.

MAIN OUTCOMES

Separate PEQ-MS and 2MWT multiple regression models fit using backward deletion.

RESULTS

Modifiable (balance ability, ABC, Houghton score; P<0.05) and non-modifiable factors (sex, amputation cause, surgical level; P<0.05) explained the variance in 2MWT (adjusted R²=0.685). Patient-reported and performance-based modifiable factors (Houghton score, 2MWT; P<0.001) explained PEQ-MS variance (adjusted R²=0.660). Integumentary (P=0.022) and cardiopulmonary (P<0.001) comorbidities explained an additional 4% of PEQ-MS variance, while surgical level was insignificant.

CONCLUSIONS

Both modifiable and non-modifiable factors explained prosthetic functional mobility. Performance-based walking was explained by modifiable factors including balance ability and confidence, prosthesis and walking aid use. Patient-reported function was also explained by prosthesis and walking aid use, walking speed and medical comorbidities. Modifiable factors for objective and subjective prosthetic mobility may provide a clinical roadmap for rehabilitation.

Effect of temperature-control liner materials on long-term outcomes of lower limb prosthesis use: a randomized controlled trial protocol

Background

In people living with limb loss, addressing the resulting functional deficit with prostheses increases the risk for secondary conditions such as pressure sores, impaired blood perfusion, and injuries from accidental falls. Any of those occurrences can render the prosthesis temporarily useless, making it challenging for users to engage in many activities of daily life, including work, exercise, and social participation. Many of the described issues originate at the interface between residual limb and prosthetic socket, where the objectives of sufficient weight distribution and suspension are conflicting with the necessity to facilitate heat exchange and limit contact pressure and friction.

Recently, prosthesis liners that contain phase-change material have become commercially available, holding the promise that the micro climate at the interface between the residual limb skin and the prosthetic socket can be regulated to reduce the users’ tendency to sweat. Preliminary studies on these liners indicate that the socket temperatures inside the socket stayed lower and rose slower than in conventional liners. However, the clinical relevance of those findings remains unclear.

The purpose of this study is to investigate whether longer (6+ months) periods of use of phase-change material based temperature-control liners have clinically meaningful effects.

Methods

The protocol is a double-blind longitudinal cross-over research design. A sample of trans-tibial prosthesis users are wearing their regular gel or silicone liners for six months and phase-change material liners for another six months in a randomized sequence. Their prostheses is equipped with activity monitors to detect days when they could not wear their prosthesis. In six-week intervals, individuals’ activity, physical performance, and overall prosthesis assessment is recorded using standardized methods.

Discussion

Expected results will inform prescription and reimbursement practice of phase-change material-based prosthesis liners and will help improve and economize prosthetic fitting for people with limb loss. The design and duration of the protocol, including randomization, blinding, and within-subject comparison, will generate scientific evidence of a comparably high level. Inclusion of a comparably large sample and different climates, e.g. across all four seasons, will make findings applicable to a large number of prosthesis users.

Trial registration

Clinicaltrials.gov, NCT03428815. Registered on 12 February 2018.

Practice effect and cueing of 2-minute walk test, 6-minute walk test and 10-meter walk test in frail older adults with and without dementia - Recommendations to walk tests protocols

OBJECTIVES

1) To determine if there was a practice effect associated with walk tests performed by frail older adults with and without dementia, 2) to examine the role of systematic cueing in the walk tests for those with dementia, and 3) to make recommendations to testing protocols of the walk tests for frail older adults with and without dementia.

SETTING

Residential and day care facilities.

PARTICIPANTS

44 frail older adults with normal cognition (NON-DEM) and 39 older adults with Alzheimer's disease or dementia (DEM) who were able to walk independently for at least 15 m.

METHODS

All the participants completed multiple trials of 2-minute walk test (2MWT), 6-minute walk test (6MWT) and 10-meter walk test (10MeWT) on three separate testing occasions. The DEM group was facilitated to complete the walk tests using a progressive cueing system.

RESULTS

Significant increases in the walking performance within the same testing occasion were found in the 2MWT (NON-DEM: p = .002; DEM: p ≤ .044) and 6MWT (NON-DEM: p ≤ .004; DEM: p ≤ .002) for both groups but only in the 10MeWT (p ≤ .023) for the DEM group. Significant increases in the walking performance across testing occasions were shown in the 2MWT (p ≤ .047), 6MWT (p ≤ .005) and 10MeWT (p ≤ .039) for the NON-DEM group but not the DEM group (all p > .05). Multivariate regression analyses showed that the cognitive function of the DEM group was independently and inversely associated with the level of cueing provided during the walk tests (p ≤ .007).

CONCLUSION

Practice effect associated with the walk tests was found within and across testing occasions for frail older adults with normal cognition, and only within the same testing occasion for those with dementia. Systematic cueing should be provided for those with dementia to complete the walk tests. Testing protocols of the walk tests have been recommended for these two population groups.

Self-Managed Strength Training for Active Duty Military With a Knee Injury: A Randomized Controlled Pilot Trial

INTRODUCTION

Knee injuries among active duty military are one of the most frequent musculoskeletal injuries and are often caused by exercise or intense physical activity or combat training. These injuries pose a threat to force readiness. Our objective was to assess feasibility (including recruitment and retention rates) of three self-managed strengthening strategies for knee injuries and determine if they resulted in improvements in lower extremity strength, function, pain, and activity compared to usual physical therapy (PT) in military members.

METHODS

A pilot study using a randomized controlled trial was conducted at three outpatient military medical treatment facilities. After baseline testing, 78 active duty military members with a knee injury were randomized to 1-4 trial arms: (1) neuromuscular electrical stimulation (NMES) applied to the quadriceps muscle; (2) graduated strength walking using a weighted vest (WALK); (3) combined NMES with strength walking (COMBO); (4) usual PT alone. All groups received usual PT. The primary outcome was the rates of change in knee extensor and flexor strength over 18 weeks. Secondary outcomes explored the rates of change in functional performance, pain, and activities of daily living scale (ADLS). The primary analysis for the endpoints used repeated measures, linear mixed-effects models. This study was approved by Institutional Review Boards at all facilities.

RESULTS

The randomized sample (N = 78) included 19 participants in the PT-only, 20 in the WALK, 19 in the NMES and 20 in the COMBO groups. At baseline, there were no group differences. Fifty of the participants completed the 18-week study. The completers and non-completers differed at baseline on injury mechanism, with more completers injured during sports (45% vs 29%), and more non-completers during military training (36% vs 18%). Also, they differed in uninjured knee extension (completers 28% weaker), and uninjured knee flexion (completers 22% weaker). Adherence for self-reported daily step logs showed that the WALK group was 15% below goal and COMBO group 6% below goal. The 300 PV muscle stimulator showed the NMES group completed 34% of recommended stimulation sessions and the COMBO group 30%.Knee extension strength in the injured knee found only the COMBO group having a statistically higher improvement compared to PT-only (Change over 18 weeks: 10.6 kg in COMBO; 2.1 kg in PT-only). For the injured knee flexion changes, only the COMBO showed significant difference from PT-only (Change over 18 weeks: 7.5 kg in COMBO; -0.2 kg in PT-only). Similarly, for the uninjured knee, only the COMBO showed significant difference from PT-only in knee extension (Change over 18 weeks: 14.7 Kg in COMBO; 2.7 kg in PT-only) and knee flexion (Change over 18 weeks: 6.5 kg in COMBO; -0.2 kg in PT-only). Overall pain improved during the study for all groups with no significant group differences. Similarly, function and ADLS significantly improved over 18 weeks, with no significant group differences.

CONCLUSIONS

Knee extensor strength improvements in the COMBO group were significantly higher compared to usual PT. Pain, functional measures, and ADLS all improved during the study with no group differences. Further research is required to confirm these findings.

Repeated assessment of key clinical walking measures can induce confounding practice effects

Accurate functional outcome measures are critical for both clinical trials and routine patient assessments. Many functional outcomes improve with test repetition, a phenomenon that can confound the findings of longitudinal assessments. In this viewpoint, we tackle the poorly considered issue of practice effects in prevailing clinical walking tests based on current literature, while also presenting the original data from our own work, in which we investigated practice effects in the timed 25-foot walk (T25FW), timed-up and go (TUG), and 2-minute walk test (2MWT). In these tests, performed on 3 consecutive days in 10 patients with multiple sclerosis and 40 healthy controls, we observed significant practice effects in several established walking outcomes, including a 9.0% improvement in patients' TUG performance (p = 0.0146). Pre-training in these walking tests prior to baseline measurement may mitigate practice effects, thereby improving the accuracy and value of their repeated use in research and clinical settings.

Using Clinical Balance Tests to Assess Fall Risk among Established Unilateral Lower Limb Prosthesis Users: Cutoff Scores and Associated Validity Indices

BACKGROUND

Clinicians are routinely required to make decisions about fall risk among lower limb prosthesis (LLP) users. These decisions can be guided by standardized clinical balance tests but require population- and test-specific cutoff scores and validity indices to categorize individuals as probable fallers or nonfallers on the basis of test performance. Despite the importance of cutoff scores and validity indices to clinical interpretation of clinical balance test scores, they are rarely reported for LLP users. In their absence, clinicians cannot use results from clinical balance tests to assess the likelihood of a fall by any one patient.

OBJECTIVE

Derive cutoff scores, and associated validity indices, for clinical balance tests administered to established unilateral LLP users.

DESIGN

Cross-sectional study.

SETTING

Outpatient clinic and research laboratory.

PARTICIPANTS

Established ambulatory unilateral transtibial and transfemoral prosthesis users (n = 40).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURE(S)

Optimal cutoff scores and related validity indices (ie, area under the curve, sensitivity, specificity, likelihood ratios) were computed for five balance tests, the activities-specific balance confidence scale (ABC), timed up and go (TUG), four square step test (FSST), Berg balance scale (BBS), and narrowing-beam walking test (NBWT).

RESULTS

Cutoff scores were identified for the NBWT (≤.43/1.0), TUG (≥8.17 seconds], FSST (≥8.49 seconds), BBS (≤50.5/56), and ABC (≤80.2/100). Validity indices (ie, area under the curve, sensitivity, specificity, and likelihood ratios) for the NBWT, TUG, and FSST had greater diagnostic accuracy and provided more information about the probability of a fall than those for the BBS or ABC.

CONCLUSION

Performance above or below identified cutoff scores for the NBWT, FSST, and TUG provides information about potentially important shifts in the probability of falling among established unilateral LLP users. These results can serve as initial benchmarks to reduce uncertainty surrounding fall risk assessment in established unilateral LLP users but require future prospective evaluation.

LEVEL OF EVIDENCE

III.

Physical Function and Pre-Amputation Characteristics Explain Daily Step Count after Dysvascular Amputation

BACKGROUND

People with dysvascular lower limb amputation (LLA) achieve one-third of the recommended steps per day and experience severe disability. Although physical function improves with rehabilitation after dysvascular LLA, physical activity remains largely unchanged, and factors contributing to limited daily step count are unknown.

OBJECTIVES

To identify factors that contribute to daily step count after dysvascular LLA.

DESIGN

Cross-sectional, secondary data analysis.

SETTING

Outpatient rehabilitation facilities.

PARTICIPANTS

Fifty-eight patients with dysvascular major LLA (age: 64 ± 9 years, body mass index: 30 ± 8 kg/m² , male: 95%, transtibial LLA: 95%).

METHODS

Data were collected by a blinded assessor after dysvascular LLA. Candidate explanatory variables included (1) demographics, (2) LLA characteristics, (3) comorbidities and health behaviors, and (4) physical function. Variables with univariate associations with log steps/day (transformed due to non-normality) were included in a multiple linear regression model using backward elimination to identify factors that explained significant variability in log steps/day.

PRIMARY OUTCOME MEASURE

The primary outcome, daily step count, was measured with accelerometer-based activity monitors worn by participants for 10 days.

RESULTS

Participants took an average (± SD) of 1450 ± 1309 steps/day. After backward elimination, the final model included four variables explaining 62% of the overall daily step count (P < .0001): 2-minute walk distance (32%), assistive device use (11%), cardiovascular disease (10%), and pre-amputation walking time (11%).

CONCLUSIONS

Average daily step count of 1450 steps/day reflects the lowest category of sedentary behavior. Physical function, cardiovascular disease, and pre-amputation walking time explain 62% of daily step count after dysvascular LLA. Although physical rehabilitation commonly focuses on improving physical function, interventions to increase daily step count after dysvascular LLA should also consider chronic disease and health behaviors that predate LLA.

LEVEL OF EVIDENCE

III.

Psychometric Properties of Functional, Ambulatory, and Quality of Life Instruments in Lower Limb Amputees: A Systematic Review

OBJECTIVE

Summarize the psychometric properties of functional, ambulatory, and quality of life instruments among adult lower limb amputees, highlighting evidence deemed generalizable to the United States Medicare population.

DATA SOURCES

Six databases and existing systematic reviews through October 30, 2017. Searches included terms for lower limb amputation or prostheses and outcome measures in humans, without language restriction.

STUDY SELECTION

We included peer-reviewed studies of at least 20 adults (≥18 years) with lower limb amputation. Eligible studies reported on psychometric properties of functional, ambulatory, or quality of life instruments. Fifty-three of 425 retrieved articles (12%) met criteria.

DATA EXTRACTION

Study characteristics and psychometric property data (validity, reliability, responsiveness, minimum detectable change, minimal important difference, or floor or ceiling effect) were extracted into a customized form based on standardized criteria. All extracted data were confirmed by 2 experts in systematic review and rehabilitation outcome measurement. Instruments were categorized regarding having been validated and found reliable. Other reported psychometric properties were recorded. Studies were also assessed for applicability to the Medicare population based on age and amputation etiology (dysvascular).

DATA SYNTHESIS

Fifty-six studies (in 53 articles) reported psychometric properties of 50 instruments. There is evidence for both validity and reliability for 30 instruments, 17 of which have evidence that was deemed generalizable to the Medicare population. Most of the remaining instruments have evidence of either validity or reliability, but not both. Twelve instruments have been assessed specifically among lower limb amputees prior to prosthesis prescription. Thirteen instruments have been assessed regarding their predictive properties for future outcomes.

CONCLUSIONS

Numerous instruments assessing ambulation, function, quality of life, and other patient-centered outcomes have evidence of validity and reliability for adults with lower limb amputations. Researchers and clinicians should use validated, reliable instruments when feasible. Many existing and new instruments require validation for use with lower limb amputees.

Two-minute versus 6-minute walk distances during 6-minute walk test in neuromuscular disease: Is the 2-minute walk test an effective alternative to a 6-minute walk test?

Functional tests such as Motor Function Measure-32 (MFM-32), supine to stand, ascend/descend stairs permit the assessment of task-specific motor function in neuromuscular disease (NMD). The 6-min walk test (6MWT), though functional, is primarily used to assess endurance and disease progression in children with neuromuscular disorders. Barriers to 6MWT administration, in this population, can include reduced attention span due to age and inability to tolerate test length due to weakness. We propose task-specific functional deficits are related to endurance. Additionally, the 2-min walk test (2MWT) could effectively replace the 6MWT in this population. Seventy-seven participants, ages 5-18, with a variety of neuromuscular disorders performed the 6MWT, timed functional tests (TFT), and the MFM-32. Correlation and paired t-test analyses were used to compare the distance walked in the first 2 min (2MWD) to the distance walked in the entire 6 min (6MWD) and to the functional outcome measures above. The 2MWD strongly correlated with 6MWD and the other outcome measures. Paired t-test analysis also showed that the 2MWD did not differ from the distance walked in the last 2 min of the 6MWT. Although equivalence testing could not reject the claim that this difference exceeded the upper practical limit of 9.5 m, it only showed a modest overestimation of the 4-6MWD compared with the 2MWD. Together, our results support the ability of the 2MWD to predict the 6MWD, specifically in the pediatric neuromuscular disease population.