Development and reliability testing of the Comprehensive High-Level Activity Mobility Predictor (CHAMP) in male servicemembers with traumatic lower-limb loss

Use of standardized outcome measures for people with lower-limb amputation: A survey of prosthetic practitioners in Canada

BACKGROUND

Outcome measures (OMs) are useful tools; however, clinicians may find implementing them into clinical practice challenging.

OBJECTIVES

To characterize Canadian prosthetists' use of OMs for people with lower-limb amputation, including motivations for use, comfort selecting OMs, resources available for administration, and barriers to implementation.

METHODS

A cross-sectional study was conducted between March and July 2021. Orthotics Prosthetics Canada sent Canadian prosthetists an invitation to take the online survey.

RESULTS

Forty-nine Certified Prosthetists completed the survey. Only 16% of participants reported that they were expected to use OMs. Participants reported being more comfortable administering performance-based OMs than self-report surveys. More than two-thirds of participants agreed that OMs "can be administered with knowledge they have" and are "within their scope of practice." However, less than 25% agreed that OMs are "administered in a standardized way in the profession," and less than 40% indicated they are "easy to make part of my routine." Participants reported they generally have time and space to do OMs, but there was no agreed-on reason to use them.

CONCLUSIONS

Use of OMs among Canadian prosthetists seems to be low relative to prosthetists in the United States. Education, financial incentives, or changes to professional expectations are likely needed to increase routine OM use. Efforts to improve the standardization of OM administration and ease the incorporation of OMs into routine practice may also increase use. Canadian prosthetists may elevate their standards of clinical practice and better understand the impact of prosthetic treatments on their patients by more routinely using OMs.

Categorization and recommendations for outcome measures for lower limb absence by an expert panel

BACKGROUND

Understanding the psychometric strengths and limitations of outcome measures for use with people with lower limb absence (LLA) is important for selecting measures suited to evaluating patient outcomes, answering clinical and research questions, and informing health care policy. The aim of this project was to review the current psychometric evidence on outcome measures in people with LLA to determine which measures should be included in a stakeholder consensus process.

METHODS

An expert panel was assembled, and a 3-stage review process was used to categorize outcome measures identified in a systematic literature review into 3 distinct categories (recommended for measures with better than adequate psychometric properties; recommended with qualification; and unable to recommend). Panelists were asked to individually categorize measures based on results of a systematic review of identified measures' psychometric properties. Each measure's final categorization was based on ≥70% agreement by all panelists.

RESULTS

No outcome measure attained the ≥70% consensus threshold needed to achieve a rating of "recommend." Hence, panelists suggested combining "recommend" and "recommend with qualifications" into a single category of "recommend with qualifications." Using this approach, consensus was reached for 59 of 60 measures. Consensus could not be reached on 1 outcome measure (socket comfort score). Thirty-six outcome measures were categorized as "unable to recommend" based on available evidence; however, 23 (12 patient-reported measures and 11 performance-based measures) demonstrated adequate psychometric properties in LLA samples and were thus rated as "recommend with qualification" by the expert panel. The panel of experts were able to recommend 23 measures for inclusion in the subsequent stakeholder review. A key strength of this process was bringing together international researchers with extensive experience in developing and/or using LLA outcome measures who could assist in identifying psychometrically sound measures to include in a subsequent stakeholder consensus process.

CONCLUSION

The above categorizations represent the current state of psychometric evidence on outcome measures for people with LLA and hence may change over time as additional research becomes available. The results will be used to achieve wider consensus from clinicians, health policymakers, health clinic managers, researchers, and end users (i.e., individuals with LLA) on outcome measures for the International Society of Prosthetics and Orthotics lower limb Consensus Outcome Measures for Prosthetic and Amputation ServiceS.

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.

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.

High-Level Mobility of Trans-Tibial Prosthesis Users Wearing Commercial and sPace Energy-Storing Prosthetic Feet

Outcomes of users provided with a commercial ESR Vari-Flex foot (Össur, Reykjavik, Iceland) and a locally designed sPace foot were investigated. Step activity with users' own prosthetic foot compared to the sPace foot was explored.

METHODS

Eleven individuals with unilateral trans-tibial amputation participated and were provided with an sPace and Vari-Flex foot. Ten- and twenty-meter walk tests (10/20MWT) at comfortable and fast walking speeds (CWS/FWS), the two-minute walk test (2-MWT) and Comprehensive High-Level Activity Mobility Predictor (CHAMP) were administered. A subgroup was provided a pedometer to record their steps over a 7-day period in their own foot and later the sPace.

RESULTS

The sPace foot performed well in a battery of high-level mobility outcome measures. On CHAMP, participants scored 16.94 ± 5.41 and 16.72 ± 6.09 with the sPace and Vari-Flex feet, respectively. Subgroup testing of step activity showed 4490 ± 3444 steps in users' own feet and 3115 ± 1967 in the sPace foot, p = 0.176.

CONCLUSIONS

Participants using the sPace foot were capable of performing walking, high-level mobility and activity outcome measures.

A modified passive-dynamic ankle-foot orthosis: can it prevent amputation and arthrodesis in patients with ankle-foot trauma?

INTRODUCTION

High-energy lower extremity trauma (HELET) may cause severe damage within the foot-ankle complex. Occasionally, arthrodesis or amputation are the only remaining options to increase activity levels. The modified passive dynamic ankle-foot orthosis (PDAFO) may prove to be a nonsurgical alternative. This study evaluated the effect of a modified PDAFO with a 6-week training program on pain and performance in patients after HELET.

MATERIALS AND METHODS

A retrospective cohort study was conducted on seventeen patients who considered an arthrodesis or an amputation after HELET. In an attempt to avoid surgery, the modified PDAFO with a 6-week training program was provided. Pain scores was measured with the Numeric Rating Scale and administered at the start of testing, immediately after the two performance tests and at the end of the day of testing. Performance was evaluated with the 6-min walk test (6MWT) and the Comprehensive high-level activity mobility predictor (CHAMP).

RESULTS

A significant pain reduction was achieved after the treatment procedure. At the start of the test days (p = 0.002), after the 6MWT (p = 0.001), after the CHAMP (p < 0.001) and at the end of the day (p < 0.001). In addition, a significant improvement on performance was observed in the 6MWT (p < 0.001) and the CHAMP (p = 0.01). None of the patients considered a surgical intervention anymore.

CONCLUSIONS

Patients after HELET show a decrease in pain and an improvement in performance after a 6-week training program with modified PD-AFO. The results suggest that the modified PDAFO is an effective alternative for a surgical approach.

Use of Standardized Outcome Measures for People With Lower Limb Amputation: A Survey of Prosthetic Practitioners in the United States

OBJECTIVE

To assess the clinical resources available for the assessment of health outcomes in people with lower limb amputation and to understand barriers and facilitators associated with use of standardized outcome measures in clinical practice.

DESIGN

Cross-sectional survey.

SETTING

General community (online).

PARTICIPANTS

A volunteer sample of prosthetic practitioners was recruited through national professional organizations. Eligible participants were practitioners certified by a professional prosthetics organization and currently practicing as a prosthetist, prosthetist-orthotist, or prosthetic assistant.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

A custom-designed online survey on clinical use of patient-reported and performance-based standardized outcome measures to assess patients with lower limb amputation.

RESULTS

A total of 375 participants completed the survey. Most participants (79%) reported that they are encouraged or required to administer standardized outcome measures in their clinic or facility. Most participants reported that use of patient-reported and performance-based outcome measures are within their scope of practice (88%) and that they have the knowledge required for outcomes measurement (84%). Few participants agreed that outcomes measurement is standardized across the profession (30%). Most participants had access to small spaces and equipment for outcomes measurement, such as short hallways (65%-94%), stairs (69%), and tablets with wireless internet connection (83%). Most participants reported that they would be willing to spend between 5 (36% of participants) and 10 (43% of participants) minutes on self-reported surveys, and between 10 (41% of participants) and 20 (28% of participants) minutes on performance-based tests.

CONCLUSIONS

Outcomes measurement is encouraged or expected in contemporary prosthetic practice. Strategies to improve standardization and efficiency of administration are needed to facilitate routine use of outcome measures in clinical care.

Clinical Resources for Assessing Mobility of People with Lower-Limb Amputation: Interviews with Rehabilitation Clinicians

Introduction

Mobility tests are increasingly used in prosthetic rehabilitation to evaluate patient outcomes. Knowledge of the space, equipment, and time resources available to clinicians who work in different settings can guide recommendations for which tests are most clinically-feasible and promote coordination of mobility testing among members of the rehabilitation team. The primary aim of this study was to characterize the different resources available to clinicians for measuring mobility of people with lower limb amputation. A secondary aim was to identify performance tasks that clinicians use to evaluate prosthetic mobility.

Materials and methods

Semi-structured interviews were conducted with prosthetists, physical therapists, and physiatrists who treat people with lower limb amputation. Researchers used convenience and snowball sampling to identify participants. Interviews included questions about the resources available for conducting mobility tests, as well as questions about which tasks clinicians deemed valuable to assessing mobility of patients with lower limb amputation. Interviews were audio-recorded and transcribed. Summary and frequency statistics were calculated for quantitative data; explanatory comments were summarized.

Results

Interviews were conducted with 25 clinicians (8 prosthetists, 9 physical therapists, and 8 physiatrists). Participants had access to multiple spaces and basic measurement equipment. The maximum time participants were willing to spend on performance tests varied. Physiatrists reported less time available (median=10 minutes, range 5-30 minutes) than prosthetists and physical therapists (median=30 minutes, range 5-60 minutes for both professions). Mobility tasks commonly used to evaluate patients with lower limb amputation included sit-to-stand, standing balance, walking, and varying speed. Participant comments suggested that mobility tests need to be quick, simple, and add value; existing mobility tests are beneficial but challenging to incorporate into practice; mobility tests should reflect real-world activities; and technological advancements could improve mobility testing.

Conclusions

Clinicians generally had small-to-medium spaces, basic measurement equipment, and sufficient training to administer mobility tests in their clinics. A limiting factor was time, which can be addressed through selection of efficient measures and collaboration within the rehabilitation team.

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.

Patient-reported Outcome Measures following Traumatic Lower Extremity Amputation: A Systematic Review and Meta-analysis

BACKGROUND

Outcomes after traumatic major lower extremity amputation (MLEA) have focused on surgical complications, despite the life-altering impact on patients. With advances in the surgical management of MLEA, a heightened need for consistent reporting of patient-centered outcomes (PCO) remains. This meta-analysis assesses articles for the prevalence and methods of PCO reporting among traumatic MLEA studies.

METHODS

An electronic database search was completed using Ovid MEDLINE for studies published between 2000 and 2020. Studies were included that reported any outcome of traumatic MLEA. Weighted means of outcomes were calculated when data were available. The prevalence of PCO was assessed in the categories of physical function, quality of life (QOL), psychosocial, and pain. Trends in PCO reporting were analyzed using Pearson's chi-squared test and analysis of variance when appropriate.

RESULTS

In total, 7001 studies were screened, yielding 156 articles for inclusion. PCO were evaluated in 94 (60.3%) studies; 83 (53.2%) reported physical function and mobility outcomes, 33 (21.2%) reported QOL and satisfaction measures, 38 (24.4%) reported psychosocial data, and 43 (27.6%) reported pain outcomes. There was no change in prevalence of PCO reporting when comparing 5-year intervals between 2000 and 2020 (P = 0.557).

CONCLUSIONS

Optimization of function and QOL following traumatic MLEA has become a cornerstone of surgical success; however, only 60% of studies report PCO, with no trend over the last two decades suggesting improvement. As healthcare progresses toward patient-centered care, this inconsistent means of reporting PCO calls for improved inclusion and standardization of instruments to assess function, QOL, and other patient-focused measures.

Military Service Members with Major Lower Extremity Fractures Return to Running with a Passive-dynamic Ankle-foot Orthosis: Comparison with a Normative Population

BACKGROUND

Lower extremity fractures represent a high percentage of reported injuries in the United States military and can devastate a service member's career. A passive dynamic ankle-foot orthosis (PD-AFO) with a specialized rehabilitation program was initially designed to treat military service members after complex battlefield lower extremity injuries, returning a select group of motivated individuals back to running. For high-demand users of the PD-AFO, the spatiotemporal gait parameters, agility, and quality of life is not fully understood with respect to uninjured runners.

QUESTIONS/PURPOSES

Do patients who sustained a lower extremity fracture using a PD-AFO with a specialized rehabilitation program differ from uninjured service members acting as controls, as measured by (1) time-distance and biomechanical parameters associated with running, (2) agility testing (using the Comprehensive High-level Activity Mobility Predictor performance test and Four Square Step Test), and (3) the Short Musculoskeletal Function Assessment score.

METHODS

We conducted a retrospective data analysis of a longitudinally collected data registry of patients using a PD-AFO from 2015 to 2017 at a single institution. The specific study cohort were patients with a unilateral lower extremity fracture who used the PD-AFO for running. Patients had to be fit with a PD-AFO, have completed rehabilitation, and have undergone a three-dimensional (3-D) running analysis at a self-selected speed at the completion of the program. Of the 90 patients who used the PD-AFO for various reasons, 10 male service members with lower extremity fractures who used a PD-AFO for running (median [range] age 29 years [22 to 41], height 1.8 meters [1.7 to 1.9], weight 91.6 kg [70 to 112]) were compared with 15 uninjured male runners in the military (median age 33 years [21 to 42], height 1.8 meters [1.7 to 1.9], weight 81.6 kg [71.2 to 98.9]). The uninjured runners were active-duty service members who voluntarily participated in a gait analysis at their own self-selected running speeds; to meet eligibility for inclusion as an uninjured control, the members had to be fit for full duty without any medical restrictions, and they had to be able to run 5 miles. The controls were then matched to the study group by age, weight, and height. The primary study outcome variables were the running time-distance parameters and frontal and sagittal plane kinematics of the trunk and pelvis during running. The Four Square Step Test, Comprehensive High-level Activity Mobility Predictor scores, and Short Musculoskeletal Function Assessment scores were analyzed for all groups as secondary outcomes. Nonparametric analyses were performed to determine differences between the two groups at p < 0.05.

RESULTS

For the primary outcome, patients with a PD-AFO exhibited no differences compared with uninjured runners in median (range) running velocity (3.9 meters/second [3.4 to 4.2] versus 4.1 meters/second [3.1 to 4.8], median difference 0.2; p = 0.69), cadence (179 steps/minute [169 to 186] versus 173 steps/minute [159 to 191], median difference 5.8; p = 0.43), stride length (2.6 meters [2.4 to 2.9] versus 2.8 meters [2.3 to 3.3], median difference 0.2; p = 0.23), or sagittal plane parameters such as peak pelvic tilt (24° [15° to 33°] versus 22° [14° to 28°], median difference 1.6°; p = 0.43) and trunk forward flexion (16.2° [7.3° to 23°) versus 15.4° [4.2° to 21°), median difference 0.8°; p > 0.99) with the numbers available. For the secondary outcomes, runners with a PD-AFO performed worse in Comprehensive High-level Activity Mobility Predictor performance testing than uninjured runners did, with their four scores demonstrating a median (range) single-limb stance of 35 seconds (32 to 58) versus 60 seconds (60 to 60) (median difference 25 seconds; p < 0.001), t-test result of 15 seconds (13 to 20) versus 13 seconds (10 to 14) (median difference 2 seconds; p < 0.001), and Illinois Agility Test result of 22 seconds (20 to 25) versus 18 seconds (16 to 20) (median difference 4; p < 0.001). Edgren side step test result of 20 meters (16 to 26) versus 24 meters (16 to 29) (median difference 4 meters; p = 0.11) and the Four Square Step Test of 5.5 seconds (4.1 to 7.2) versus 4.2 seconds (3.1 to 7.3) (median difference 1.3 seconds; p = 0.39) were not different between the groups with an effect size of 0.83 and 0.75, respectively.

CONCLUSION

The results of our study demonstrate that service members run with discernible differences in high-level mobility and demonstrate inferior self-reported patient functioning while having no differences in speed and biomechanics compared with their noninjured counterparts with the sample size available. This study is an early report on functional gains of highly motivated service members with major lower extremity injuries who use a PD-AFO and formalized therapy program to run.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Comparison of Ischial Containment and Subischial Sockets on Comfort, Function, Quality of Life, and Satisfaction With Device in Persons With Unilateral Transfemoral Amputation: A Randomized Crossover Trial

OBJECTIVE

To compare comfort and functional performance of the Northwestern University Flexible Subischial Vacuum (NU-FlexSIV) Socket with the ischial containment (IC) socket in persons with unilateral transfemoral amputation.

DESIGN

Randomized crossover trial with two 7-week periods.

SETTING

Private prosthetic clinics and university research laboratory.

PARTICIPANTS

A total of 30 enrolled (N=30); 25 participants completed the study with full (n=18) or partial data (n=7).

INTERVENTIONS

Two custom-fabricated sockets (IC and NU-FlexSIV), worn full-time for 7 weeks, with testing at 1, 4, and 7 weeks after socket delivery.

MAIN OUTCOME MEASURES

The primary outcome was change in Socket Comfort Score (SCS) at 7 weeks. Secondary outcomes at 7 weeks included the Orthotic and Prosthetic Users' Survey (OPUS) to assess lower extremity functional status, health-related quality of life, and satisfaction with device, as well as the 5-Times Rapid Sit-to-Stand Test, Four Square Step Test, and T-Test of Agility to assess functional performance.

RESULTS

At 7 weeks, the mean SCS for IC (7.0±1.7) and NU-FlexSIV (8.4±1.1) Sockets were significantly different (P<.001; 95% confidence interval, 0.8-2.3). Results from a linear mixed-effects model, accounting for data from all time points, indicated that the SCS was 1.7 (SE=0.45) points higher for the NU-FlexSIV Socket (P<.001). For the secondary outcomes, only OPUS satisfaction with device was significantly better in the NU-FlexSIV Socket after accounting for all data points.

CONCLUSIONS

The results suggest that after 7 weeks' accommodation, the NU-FlexSIV Socket was more comfortable and led to greater satisfaction with device than the IC socket in persons with unilateral transfemoral amputation and K3/K4 mobility. Other patient-reported outcomes and function were no different between sockets.

Validation of Accelerometry Data to Identify Movement Patterns During Agility Testing

Purpose: The purpose of this study was to develop an algorithm for the detection and timing of foot contact/off timing for each lateral repetition and assess the validity/reliability of the calculated timings.

Methods: Participants performed a modified Edgren Side Step Test in which they moved laterally along a 4-m path as quickly as possible while wearing an accelerometer on each ankle. Time of completion of each attempt was recorded using a stopwatch and digital video was obtained. Accelerometer-based (ACC) events were determined for the start of the test (START), foot contact at the end-line (FC) and the lifting of the foot when transitioning to the other direction (FO). Based on these ACC events the Overall, Split (ST) and Lag (LT) times were determined and compared to either the stopwatch or video-based timings (p < 0.05). The ACC event criterion was then applied by independent reviewers to assess inter/intra-rater reliability of identifying the events.

Results: There was no significant difference in ACC (12.37 ± 2.19 s) based Overall Time compared to the Stopwatch (12.42 ± 2.25 s, p = 0.34). Bland-Altman plots for ST and LT revealed very good agreement between the ACC time to the Video (ST: Bias = 0.11 s, LOA −0.57 to 0.79; LT: Bias = −0.11 s, LOA −0.43 to 0.22). Intra and inter-rater reliability was moderate to excellent for all reviewer identified events.

Conclusions: This study demonstrates methodology to identify ACC based timings during an agility test. The inclusion of an accelerometer supplements standard timing options with the added benefit of assessing sided split and lag times.

Selecting, Administering, and Interpreting Outcome Measures among Adults with Lower-Limb Loss: An Update for Clinicians

Purpose of review

To summarize outcome measurement research among adults with lower-limb loss (LLL) for clinicians.

Recent findings

Houghton Scale, Prosthetic Evaluation Questionnaire-mobility subscale (PEQ-m), Prosthetic Limb Users Survey of Mobility (PLUS-M™), Activities-Specific Balance Confidence Scale (ABC), Amputee Mobility Predictor (AMP), Comprehensive High-Level Activity Mobility Predictor, Four Square Step Test (FSST), Narrowing Beam Walking Test (NBWT), L Test, 10 Meter Walk Test (10MWT), and 6 Minute Walk Test (6MWT) are appropriate for evaluating individual patient changes post-LLL. Post-LLL, Socket Comfort Score, Patient-Specific Functional Scale, Patient-Reported Outcomes Measurement Information System 29-Item Profile, Timed Up and Go, and 2 Minute Walk Test may be more appropriate for evaluating groups. Minimal detectable change is available for 15/20 reviewed measures. Many measures differ between mobility levels.

Summary

Quick, reliable measures for evaluating patient functional change include ABC, PEQ-m, PLUS-M™, FSST, and L Test; when resources allow, NBWT, 10MWT, 6WMT and AMP may be considered.

Estimated forces and moments experienced by osseointegrated endoprostheses for lower extremity amputees

BACKGROUND

Percutaneous osseointegrated (OI) docking of prosthetic limbs returns loading directly to the residual bone of individuals with amputations. Lower limb diaphyseal biomechanics have not been studied during the wide range of daily activities performed by individuals with lower extremity amputations; therefore, little is known about the loads experienced at the bone-endoprosthetic interface of a percutaneous OI device.

RESEARCH QUESTION

Does residual limb length and/or gender influence loading magnitudes in the diaphysis of the femur or tibia during daily activities?

METHODS

This observational study used motion capture data from 40 non-amputee volunteers performing nine activities ranging from low to high demand, to virtually simulate residual limbs of amputees. To simulate diaphyseal bone loading in individuals with lower limb amputations, virtual joints were defined during post-processing at 25, 50, and 75 % of residual limb length of both the femur and the tibia, representing six clinically relevant residual limb lengths for OI device placement. Peak axial distractive and compressive forces, torsional moments, and bending moments were calculated for each activity. Comparisons were made between genders and between different levels of the simulated residual limb.

RESULTS

For simulated above and below knee amputations, short residual limbs showed the highest average bending, torsion, and axial distractive loads, while axial compressive loads were highest for long residual limbs. Absolute maxima for all subjects showed this same trend, except in below knee torsion, where 75 % residual tibia length showed the maximum. The highest demand activities yielding peaks in all directions were cutting with right leg planted, jump, run, and fall.

SIGNIFICANCE

Overall, individuals with shorter residual limbs experienced higher diaphyseal forces. This should be taken into consideration during surgical implantation of percutaneous OI devices where residual limb length can potentially be shortened, and during rehabilitation of percutaneous OI patients.

Validity of the Comprehensive High-Level Activity Mobility Predictor in a heterogeneous population with lower extremity amputations

BACKGROUND AND OBJECTIVE

Lower extremity amputee outcome measures assess basic mobility. The Comprehensive High-Level Activity Mobility Predictor was developed to assess high-level mobility. Validity evidence was collected in military men with traumatic lower extremity amputations. This study examines its validity in a broader population.

STUDY DESIGN

Cross-sectional.

METHODS

Forty-five lower extremity amputees (Medicare Functional Classification Level K3 or K4) completed the 2-min walk test, Amputee Mobility Predictor with Prosthesis, and Comprehensive High-Level Activity Mobility Predictor.

RESULTS

The Comprehensive High-Level Activity Mobility Predictor correlated with the Amputee Mobility Predictor with Prosthesis (r = 0.77, p < 0.01) and the 2-min walk test (r = 0.65, p < 0.01). The Comprehensive High-Level Activity Mobility Predictor differentiated between K-levels, age groups, etiology of amputation, and amputation level (p < 0.005). No ceiling effect was observed (range: 2.5-29/40).

CONCLUSION

This study provides convergent and discriminative validity evidence for Comprehensive High-Level Activity Mobility Predictor use in a more heterogeneous population than previously published, suggesting that clinicians should feel confident to use it as an outcome measure for individuals with amputations who are capable of more than level-ground walking.

CLINICAL RELEVANCE

Clinically, the Comprehensive High-Level Activity Mobility Predictor has validity evidence for use in a more heterogeneous population than originally demonstrated, including civilians, women, people over age 40 years, and non-traumatic etiologies. The Comprehensive High-Level Activity Mobility Predictor may be more useful than standard outcome measures for high-level mobility.

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.

Quantification of Agility Testing with Inertial Sensors after a Knee Injury

INTRODUCTION

A common criterion in decision making regarding return to sport (RTS) after knee ligament injury is that athletes should achieve symmetrical bilateral movement between the injured limb and the noninjured limb. Body-worn wireless inertial measurement units (IMU) can provide clinicians with valuable information about lower-limb kinematics and athletic performance.

METHODS

The IMU-based novel kinematic metrics were developed. The Transitional Angular Displacement of Segment (TADS) and Symmetry Index (SI) measures that quantify lower-limb motions and interlimb symmetry during the 4-m side step test (FmSST) were developed. Test-retest reliability was measured in 20 healthy adults. Experimental application of the metrics was also determined in 15 National Collegiate Athletic Association Division I collegiate athletes who completed rehabilitation after a knee ligament injury.

RESULTS

The intraclass correlation coefficient for test-retest reliability for FmSST, TADS right lower limb, TADS left lower limb, and TADS SI was 0.90 (95% confidence interval, [0.61-0.95]); 0.87 [0.63-0.96]; 0.89 [0.64-0.96], and 0.81 [0.58-0.92], respectively. The differences between TADS SI at baseline (preinjury) and RTS were also compared with those between the total times for performing the FmSST at baseline and RTS. There was no significant difference in the FmSST times between baseline and RTS (P = 0.32); however, TADS SI at the time of RTS was significantly lower than at baseline (P = 0.046). A large effect size (d = -1.04) was observed for the change in TADS SI from baseline to RTS.

CONCLUSIONS

Using IMU sensor technology can provide quantitative and discrete analysis to detect kinematic differences during agility after a knee ligament injury in the field or nonlaboratory setting. This approach has the potential to help clinicians improve decisions about rehabilitation at a time when an athlete is reintegrating back into sport.

High-Level Performance After the Return to Run Clinical Pathway in Patients Using the Intrepid Dynamic Exoskeletal Orthosis

BACKGROUND

Severe ankle and foot injuries in the US military can result in high-level functional limitation, lost duty days, and medical discharge.

OBJECTIVE

To assess the effectiveness of the Return to Run Clinical Pathway (RTR) in returning patients with lower extremity fractures who utilized the Intrepid Dynamic Exoskeletal Orthosis (IDEO) to high-level mobility.

METHODS

Thirty servicemembers with lower extremity fractures who utilized the IDEO unilaterally and completed the RTR at Naval Medical Center San Diego were included in this retrospective operational review. The Comprehensive High-level Activity Mobility Predictor (CHAMP) and all subtests were completed prior to and after completion of the RTR as part of routine clinical care. An analysis of covariance (ANCOVA) was used to compare CHAMP scores before and after the RTR.

RESULTS

Significant improvements were found in the T test (mean change, faster by 5.3 seconds; 95% confidence interval: 3.6, 7.1 seconds; P = .03) and total CHAMP score (mean change, 4.2 points; 95% confidence interval: 3.0, 5.3 points; P<.05). No significant changes were noted in the single-legged stance subtest, the Edgren sidestep test, or the Illinois agility test.

CONCLUSION

The RTR led to improvements in high-level, multidirectional mobility in IDEO users with a history of fractures. Applicability of the intervention used in this study requires further validation before widespread use.

LEVEL OF EVIDENCE

Therapy, level 4. J Orthop Sports Phys Ther 2019;49(7):529-535. Epub 13 Feb 2019. doi:10.2519/jospt.2019.8763.

Assessment of low- and high-level task performance in people with transtibial amputation using crossover and energy-storing prosthetic feet: A pilot study

BACKGROUND:

Crossover feet incorporate features of energy-storing feet and running-specific feet. As such, crossover feet may be suitable for both daily ambulation and participation in physically demanding activities.

OBJECTIVES:

To compare crossover feet and energy-storing feet on performance-based tests including a range of low-level (e.g. sit-to-stand) and high-level (e.g. jogging) activities.

STUDY DESIGN:

Cross-sectional, repeated measures.

METHODS:

Participants with transtibial amputation completed a battery of performance-based outcome measures, including the Five Times Sit-to-Stand, Timed-Up-and-Go, Four Square Step Test, and the Comprehensive High-level Activity Mobility Predictor. Participants wore duplicate prostheses fit with crossover feet and energy-storing feet to perform the tests; the order of foot conditions was randomized. Paired t tests were used to evaluate differences between feet and order of testing.

RESULTS:

Data from seven participants showed improvements in all measures while using crossover feet. Improvements in the second foot condition were also observed, indicating a practice effect for all measures. However, differences between feet and order of conditions were not statistically significant ( p > 0.05).

CONCLUSION:

Results of this study suggest that crossover feet may improve low- and high-level mobility outcomes. However, intervention effects are small and practice effects were observed in all outcomes. Future research is needed to evaluate the influence of practice effects on performance-based mobility measures.

CLINICAL RELEVANCE

Crossover feet may improve transtibial prosthesis users' performance compared to energy-storing feet across a range of activities, but additional research is needed. Practice effects may be an influential factor in the measurement of performance-based mobility outcomes and should be considered when performing a clinical assessment.

Reliability, Validity, and Responsiveness of Clinical Performance-Based Outcome Measures of Walking for Individuals With Lower Limb Amputations: A Systematic Review

BACKGROUND

Clinical outcome measures are important to use for individuals with lower limb amputations (LLA) because such individuals require intensive functional gait training before and after being fitted with prostheses. Using standardized instruments throughout the episode of care allows clinicians to objectively monitor patient progress, make evidence-based decisions regarding the plan of care, and communicate results in meaningful ways to patients, payers, and other clinicians. Many clinical outcome measures exist, but not all have been validated and shown to be reliable within this population of interest.

PURPOSE

The aim of this review was to provide a comprehensive overview of the psychometric properties of all current performance-based outcome measures applicable to individuals with lower limb amputations.

DATA SOURCES

Reviewers searched for articles using the online databases PubMed/MEDLINE and CINAHL. Reviewers also conducted a manual search of the reference list of 1 of the previously published systematic reviews to identify any additional studies not detected with the online database search.

STUDY SELECTION

The 2 reviewers screened titles and abstracts for relevance. The same reviewers obtained and read full-text articles of the potentially relevant studies. Reviewers resolved any discrepancies of the inclusion assessment by further discussion.

DATA EXTRACTION

The reviewers created tables to extract psychometric properties of interest from the included articles. Both reviewers extracted the data from the articles and placed relevant values into a table for each primary outcome measure identified.

DATA SYNTHESIS

The rigor of study reporting was guided by use of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Checklist. Each reviewer independently read and appraised the included articles, assigning a score to each checklist item. The sum of scores for each item was calculated to appraise the overall quality of reporting of the included articles.

LIMITATIONS

Review-level limitations included the absence of a third reviewer to settle any disagreements on article inclusion and article appraisal. Additionally, the percentage of reviewer agreement on article appraisal was not determined before disagreements about checklist item satisfaction were resolved. Furthermore, reviewers only extracted data on reliability, validity, and responsiveness; instrument characteristics, such as floor and ceiling effects, are also important.

CONCLUSIONS

Valid and reliable performance-based clinical measures of ambulation in individuals with LLA were identified. Further research should investigate the minimally clinical, important difference of these clinical measures and address trends in unmet reporting guidelines.

Predict the Medicare Functional Classification Level (K-level) using the Amputee Mobility Predictor in people with unilateral transfemoral and transtibial amputation: A pilot study

BACKGROUND

While Amputee Mobility Predictor scores differ between Medicare Functional Classification Levels (K-level), this does not demonstrate that the Amputee Mobility Predictor can accurately predict K-level.

OBJECTIVES

To determine how accurately K-level could be predicted using the Amputee Mobility Predictor in combination with patient characteristics for persons with transtibial and transfemoral amputation.

STUDY DESIGN

Prediction.

METHOD

A cumulative odds ordinal logistic regression was built to determine the effect that the Amputee Mobility Predictor, in combination with patient characteristics, had on the odds of being assigned to a particular K-level in 198 people with transtibial or transfemoral amputation.

RESULTS

For people assigned to the K2 or K3 level by their clinician, the Amputee Mobility Predictor predicted the clinician-assigned K-level more than 80% of the time. For people assigned to the K1 or K4 level by their clinician, the prediction of clinician-assigned K-level was less accurate. The odds of being in a higher K-level improved with younger age and transfemoral amputation.

CONCLUSION

Ordinal logistic regression can be used to predict the odds of being assigned to a particular K-level using the Amputee Mobility Predictor and patient characteristics. This pilot study highlighted critical method design issues, such as potential predictor variables and sample size requirements for future prospective research. Clinical relevance This pilot study demonstrated that the odds of being assigned a particular K-level could be predicted using the Amputee Mobility Predictor score and patient characteristics. While the model seemed sufficiently accurate to predict clinician assignment to the K2 or K3 level, further work is needed in larger and more representative samples, particularly for people with low (K1) and high (K4) levels of mobility, to be confident in the model's predictive value prior to use in clinical practice.

Combat-related foot injuries: impact on gait and functional outcome

Introduction

Prior to deployment of the Netherlands Army Task Force Urozgan in Afghanistan, the Dutch Military and civilian healthcare systems had limited experience in treating blast injuries and their long-term consequences. This meant that guidelines for treatment and rehabilitation were lacking. The aim of this cohort study was to quantify kinematic and kinetic abnormalities in service members with foot injuries in relation to functional outcome using gait analysis.

Method

In nine service members with combat-related talus, calcaneus and/or navicular bone (TCN) fractures and nine controls, gait parameters were measured using Gait Real-Time Analysis Interactive Lab system. High-level mobility was evaluated by the Comprehensive High-Level Activity Mobility Predictor (CHAMP), and functional ability was assessed by Lower Extremity Functional Scale (LEFS) questionnaire.

Results

Significant differences were found for LEFS and CHAMP scores (P<0.01), comfortable walking speed and ankle joint range of motion (ROM) (P<0.05), all lower in the group with TCN fractures. For this group, a trend (0.1>P>0.05) for higher step width and lower stride duration and peak power was found. A strong correlation (0.6>r>0.79) is shown between LEFS and comfortable walking speed and CHAMP and ankle joint ROM. The correlations between LEFS and stride duration, step width, ankle joint ROM and peak power, and between CHAMP and comfortable walking speed and stride duration, were moderate (0.4>r>0.59).

Conclusions

This study demonstrated that service members with TCN fractures, compared with healthy controls, have altered gait characteristics, specifically lower walking speed and ankle joint ROM, both related to lower physical functioning. Patients with bilateral depressed Böhler’s angle had the worse functional performance, and further research is recommended to evaluate the relationship between Böhler’s angle and physical performance.

Clinical Trial

The Dutch Ministry of Defence (MOD) and the Institutional Review Board and Medical Ethics Review Committee Brabant, The Netherlands, approved this study (P1550).

Laboratory- and community-based health outcomes in people with transtibial amputation using crossover and energy-storing prosthetic feet: A randomized crossover trial

Contemporary prosthetic feet are generally optimized for either daily or high-level activities. Prosthesis users, therefore, often require multiple prostheses to participate in activities that span a range of mobility. Crossover feet (XF) are designed to increase the range of activities that can be performed with a single prosthesis. However, little evidence exists to guide clinical prescription of XF relative to traditional energy storing feet (ESF). The objective of this study was to assess the effects of XF and ESF on health outcomes in people with transtibial amputation. A randomized crossover study was conducted to assess changes in laboratory-based (endurance, perceived exertion, walking performance) and community-based (step activity and self-reported mobility, fatigue, balance confidence, activity restrictions, and satisfaction) outcomes. Twenty-seven participants were fit with XF and ESF prostheses with standardized sockets, interfaces, and suspensions. Participants were not blinded to the intervention, and wore each prosthesis for one month while their steps were counted with an activity monitor. After each accommodation period, participants returned for data collection. Endurance and perceived exertion were measured with the Six-Minute Walk Test and Borg-CR100, respectively. Walking performance was measured using an electronic walkway. Self-reported mobility, fatigue, balance confidence, activity restrictions, and satisfaction were measured with survey instruments. Participants also reported foot preferences upon conclusion of the study. Differences between feet were assessed with a crossover analysis. While using XF, users experienced improvements in most community-based outcomes, including mobility (p = .001), fatigue (p = .001), balance confidence (p = .005), activity restrictions (p = .002), and functional satisfaction (p < .001). Participants also exhibited longer sound side steps in XF compared to ESF (p < .001). Most participants (89%) reported an overall preference for XF; others (11%) reported no preference. Results indicate that XF may be a promising alternative to ESF for people with transtibial amputation who engage in a range of mobility activities.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02440711.

Northwestern University Flexible Subischial Vacuum Socket for persons with transfemoral amputation: Part 2 Description and Preliminary evaluation

BACKGROUND

Current transfemoral prosthetic sockets are problematic as they restrict function, lack comfort, and cause residual limb problems. Development of a subischial socket with lower proximal trim lines is an appealing way to address this problem and may contribute to improving quality of life of persons with transfemoral amputation.

OBJECTIVES

The purpose of this study was to illustrate the use of a new subischial socket in two subjects.

STUDY DESIGN

Case series.

METHODS

Two unilateral transfemoral prosthesis users participated in preliminary socket evaluations comparing functional performance of the new subischial socket to ischial containment sockets. Testing included gait analysis, socket comfort score, and performance-based clinical outcome measures (Rapid-Sit-To-Stand, Four-Square-Step-Test, and Agility T-Test).

RESULTS

For both subjects, comfort was better in the subischial socket, while gait and clinical outcomes were generally comparable between sockets.

CONCLUSION

While these evaluations are promising regarding the ability to function in this new socket design, more definitive evaluation is needed. Clinical relevance Using gait analysis, socket comfort score and performance-based outcome measures, use of the Northwestern University Flexible Subischial Vaccum Socket was evaluated in two transfemoral prosthesis users. Socket comfort improved for both subjects with comparable function compared to ischial containment sockets.

Further Development of the Assessment of Military Multitasking Performance: Iterative Reliability Testing

The Assessment of Military Multitasking Performance (AMMP) is a battery of functional dual-tasks and multitasks based on military activities that target known sensorimotor, cognitive, and exertional vulnerabilities after concussion/mild traumatic brain injury (mTBI). The AMMP was developed to help address known limitations in post concussive return to duty assessment and decision making. Once validated, the AMMP is intended for use in combination with other metrics to inform duty-readiness decisions in Active Duty Service Members following concussion. This study used an iterative process of repeated interrater reliability testing and feasibility feedback to drive modifications to the 9 tasks of the original AMMP which resulted in a final version of 6 tasks with metrics that demonstrated clinically acceptable ICCs of > 0.92 (range of 0.92–1.0) for the 3 dual tasks and > 0.87 (range 0.87–1.0) for the metrics of the 3 multitasks. Three metrics involved in recording subject errors across 2 tasks did not achieve ICCs above 0.85 set apriori for multitasks (0.64) and above 0.90 set for dual-tasks (0.77 and 0.86) and were not used for further analysis. This iterative process involved 3 phases of testing with between 13 and 26 subjects, ages 18–42 years, tested in each phase from a combined cohort of healthy controls and Service Members with mTBI. Study findings support continued validation of this assessment tool to provide rehabilitation clinicians further return to duty assessment methods robust to ceiling effects with strong face validity to injured Warriors and their leaders.

Determining 1-Yr Prosthetic Use for Mobility Prognoses for Community-Dwelling Adults with Lower-Limb Amputation: Development of a Clinical Prediction Rule

OBJECTIVE

The objective of this study was to develop a prognostic clinical prediction rule to identify people not achieving community walking level prosthetic use after 1 yr.

DESIGN

This is a prospective longitudinal cohort study of community-dwelling adults with lower-limb amputations recruited from support groups and prosthetic clinics. Participants completed Activities-specific Balance Confidence and Houghton prosthetic use for mobility self-report scales and the Berg Balance Scale. The clinical prediction rule was developed using multivariate logistic regression, receiver operating curves, and probability statistics to identify people not achieving community walking level prosthetic use (Houghton scores <9) at 1 yr.

RESULTS

Forty (74.1%) of 54 participants provided follow-up data. Participants averaged 57.0 ± 11.9 yrs old, and the most recent amputation had occurred an average of 6.6 ± 11.0 yrs ago. Seventy percent had vascular amputations and 52.5% had transtibial amputations. The clinical prediction rule predicted who would not reach the community prosthetic walking level with excellent accuracy (area under the curve >0.96) using four criteria: initial Houghton, Activities-specific Balance Confidence, and Berg Balance Scale tasks 9 (retrieve object from floor) and 10 (look behind over shoulders). Failure to exceed cutoff scores in two or more criteria yielded posttest probability of not reaching community walking prosthetic use 1 yr later for 90% of participants or higher.

CONCLUSIONS

Accurate 1-yr prosthetic use for mobility prognoses can be obtained by screening prosthetic use, balance confidence, and balance ability to identify community-dwelling people with lower-limb amputations unlikely to achieve community walking prosthetic use.