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

Virtual Assessment of Functional Mobility in Lower Extremity Prosthesis Clients: An Exploratory Study

Objective

To investigate the relationship between patient perception of lower extremity function and a home-based virtual clinician assessment of mobility in lower limb prosthesis clients.

Design

Descriptive observational study using a clinician-administered functional mobility survey and timed Up and Go test to assess lower extremity function under supervision.

Setting

Health Insurance Portability and Accountability Act-compliant online virtual platform.

Participants

Twelve lower limb loss clients currently using prostheses, aged ≥19 years, not pregnant, and with no stroke, seizure disorder, or cancer.

Interventions

Not applicable.

Main Outcome Measures

Main outcomes were mobility survey scores and mean timed Up and Go duration.

Results

Most participants reported significant ease of completing basic indoor ambulation and toileting tasks (66%-75%) and significant difficulty in running or prolonged ambulation activities (83%) requiring use of lower limb prosthesis. Timed Up and Go test was faster (11.0±2.9 s) than the reference range for transtibial prosthesis users and negatively associated with self-reported lower extremity functional status (r=-.70, P=.02).

Conclusions

Self-reported movement with lower limb prostheses at home and evaluation of mobility via a virtual platform is a feasible assessment modality that may reduce the frequency of therapy visits, defray some rehabilitation costs, and minimize the travel burden to distant prosthetic clinics.

Creation of a Limb Loss and Preservation Registry for Improving the Quality of Patient Care in the United States

Objective

To describe the development of a national Limb Loss and Preservation Registry (LLPR) designed to collect, standardize, and report patient outcomes data on limb loss and limb difference in the United States.

Design

Clinical Data Registry.

Setting

The LLPR was developed through consensus of key stakeholders from academia, industry, patient advocacy, and payers as well as the available scientific evidence. Data are collected from multiple sources, including hospitals, providers, and patients.

Participants

Data are collected from all 50 states.

Interventions

Not applicable.

Main Outcome Measures

More than 1100 trigger codes are used to identify patients who have limb difference or have received a limb preservation or amputation procedure. Once a patient is identified, all subsequent episodes of care are collected for the life of the patient. An integrated model is used for collecting, validating, cleaning, transforming, aggregating, and storing the data received from all sources. The information contained is then provided in a thorough and easily comprehensible manner.

Results

To date, the LLPR has captured data from >435,000 patients and >11.5 million episodes of care.

Conclusions

The LLPR creates opportunities to apply large-data analytical methodologies to provides caregivers, researchers, manufacturers, payers, and policy makers the tools needed to improve the quality of clinical care, quantify patient-centric outcomes, develop clinical practice guidelines, assess patient quality of life, identify appropriate technology, and guide creation of national policies to allocate scarce sources appropriately.

Daily steps and stepping cadence increase one-year following prosthesis osseointegration in people with lower-limb amputation

PURPOSE

People with lower-limb loss participate in less physical activity than able-bodied individuals, which increases the mortality risk and incidence of metabolic syndromes. This study evaluated the effect of lower-limb prosthesis osseointegration on physical activity, including daily steps and stepping cadence.

METHODS

Free-living walking activity was assessed from 14 patients scheduled to undergo prosthesis osseointegration at two time points (within 2 weeks prior to osseointegration surgery and 12-months following). Daily step count, stepping time, number of walking bouts, average step cadence per bout, maximum step cadence per bout, and time spent in bands of step cadence were compared before and after osseointegration.

RESULTS

Twelve months after prosthesis osseointegration, participants increased daily steps, daily stepping time, average step cadence, and maximum cadence per walking bout compared to pre-osseointegration.

CONCLUSIONS

Participants engaged in more daily steps, higher stepping cadence, and longer bouts at higher cadence one year following osseointegration compared to when using a socket prosthesis. As a novel intervention that is becoming more common, it is important to understand walking activity outcomes as these are critical for long-term health.

Sarcopenia is associated with lower step count in patients with peripheral artery disease following endovascular treatment

INTRODUCTION

Patients with peripheral artery disease (PAD) often complain of reduced physical activity (PA) despite improvements in intermittent claudication after successful endovascular treatment (EVT). Sarcopenia resulting from chronic ischemia can affect post-EVT PA levels.

OBJECTIVE

This study aims to assess the association between sarcopenia and post-EVT PA levels.

METHODS

One hundred five patients with PAD were consecutively enrolled in this study. PA was assessed using the post-EVT step count and the pre-EVT International Physical Activity Questionnaire. Sarcopenia was diagnosed based on the Asia Working Group for Sarcopenia and defined as low muscle mass and strength, and/or slow walking speed. The patients were categorized into three groups: 1) patients with sarcopenia (Sarcopenia Group); 2) patients with only low muscle mass or strength, and/or slow walking speed (Suspected-Sarcopenia Group); and 3) patients who did not fulfill all the sarcopenia criteria (No-Sarcopenia Group).

RESULTS

Proportions of patients in the Sarcopenia, Suspected-Sarcopenia, and No-Sarcopenia Groups were 31.4, 38.1, and 30.5%, respectively. After controlling for potential confounders, the Sarcopenia Group demonstrated significantly lower step counts than the Suspected-Sarcopenia Group (p = .016) and No-Sarcopenia Group (p = .009).

CONCLUSIONS

Our findings indicate that patients with PAD and sarcopenia require rehabilitation strategies to enhance physical performance.

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.

Effect of Function-Based Approach to Nontraumatic Major Lower Extremity Amputation on 5-Year Mortality

BACKGROUND

Five-year mortality rates after lower extremity amputation in the chronic wound population have long been regarded as high and inevitable. We theorize that function-based surgical technique and multidisciplinary care improve mortality and assess our institution's mortality rates after major lower extremity amputation (MLEA).

STUDY DESIGN

We performed a retrospective review of patients who underwent primary nontraumatic MLEA at our institution from 2010 to 2013. Major amputations included below knee amputation, through knee amputation, and above knee amputation. Our function-based surgical approach to MLEA is guided by 4 tenets: (1) optimization of limb biomechanics, (2) maximal soft tissue preservation, (3) multidisciplinary team approach, and (4) addressing nerves during primary amputation to prevent postamputation pain. Kaplan-Meier analysis and Cox regression were performed to estimate cumulative 5-year mortality and to identify predictors of 5-year mortality, respectively.

RESULTS

A total of 188 patients underwent MLEA. Median Charlson Comorbidity Index was 4. Estimated 5-year mortality was 40% overall and 43% for diabetic patients. When stratified by amputation level, 5-year mortalities were 36.3% for below knee amputation, 60.9% for through knee amputation, and 44.0% for above knee amputation. Charlson Comorbidity Index (hazard ratio 1.24, p < 0.001) and end-stage renal disease (hazard ratio 3.38, p < 0.001) were the strongest predictors of 5-year mortality.

CONCLUSIONS

We demonstrate the lowest mortality rate reported for MLEA. Improved functional and mortality outcomes can be achieved with a function-based surgical approach to MLEA and close follow-up by a multidisciplinary team. Future studies, using standardized reporting of mortality data and incorporating patient-reported outcomes, are warranted to correlate return to function and mortality.

Self-reported health condition severity and ambulation status postmajor dysvascular limb loss

BACKGROUND

Individuals with dysvascular lower limb amputations (LLA) secondary to complications of peripheral arterial disease (PAD) and/or diabetes have high rates of co-morbidities.

OBJECTIVES

To describe self-reported health condition severity and their association with sociodemographic factors and ambulations status among individuals with major dysvascular LLA.

STUDY DESIGN

Cross sectional telephone and in person survey with adults with major dysvascular LLA living in the community setting in Ontario, Canada.

METHODS

Survey by phone/in person, and completion of the Dysvascular Conditions Scale and Special Interest in Amputee Medicine Mobility (SIGAM) Grade by each participant.

RESULTS

Two hundred thirty-one individuals with major dysvascular LLAs participated in the study. Most of them were male individuals (80.5%) and had undergone a transtibial amputation (74%). On average, participants were 3.4 years postlimb loss and had five identified Dysvascular Conditions Scale health conditions. The top five reported health conditions were diabetes, hypertension, phantom limb pain, musculoskeletal pain, and back pain. With the exclusion of hypertension, these conditions were also perceived by respondents to be quite severe for their impact. Vision impairment was also rated as being severe in nature. Lower mobility Special Interest Group in Amputee Medicine grades were associated with higher health condition severity scores.

CONCLUSIONS

Individuals with dysvascular limb loss experience high multimorbidity with perceived negative impact on their overall wellness and function. Rehabilitation and self-management strategies to help patients with dysvascular LLAs to manage chronic health conditions may improve outcomes.

Reported Outcome Measures in Studies of Real-World Ambulation in People with a Lower Limb Amputation: A Scoping Review

BACKGROUND

The rapidly increasing use of wearable technology to monitor free-living ambulatory behavior demands to address to what extent the chosen outcome measures are representative for real-world situations. This scoping review aims to provide an overview of the purpose of use of wearable activity monitors in people with a Lower Limb Amputation (LLA) in the real world, to identify the reported outcome measures, and to evaluate to what extent the reported outcome measures capture essential information from real-world ambulation of people with LLA.

METHODS

The literature search included a search in three databases (MEDLINE, CINAHL, and EMBASE) for articles published between January 1999 and January 2022, and a hand-search.

RESULTS AND CONCLUSIONS

98 articles met the inclusion criteria. According to the included studies' main objective, the articles were classified into observational (n = 46), interventional (n = 34), algorithm/method development (n = 12), and validity/feasibility studies (n = 6). Reported outcome measures were grouped into eight categories: step count (reported in 73% of the articles), intensity of activity/fitness (31%), type of activity/body posture (27%), commercial scores (15%), prosthetic use and fit (11%), gait quality (7%), GPS (5%), and accuracy (4%). We argue that researchers should be more careful with choosing reliable outcome measures, in particular, regarding the frequently used category step count. However, the contemporary technology is limited in providing a comprehensive picture of real-world ambulation. The novel knowledge from this review should encourage researchers and developers to engage in debating and defining the framework of ecological validity in rehabilitation sciences, and how this framework can be utilized in the development of wearable technologies and future studies of real-world ambulation in people with LLA.

A Scoping Review of Physical Activity in People With Lower-Limb Loss: 10,000 Steps Per Day?

OBJECTIVE

After amputation, people with lower-limb loss (PLL) face challenges to regain their previous physical activity level. Assessing the scope of evidence regarding physical activity in PLL can identify sources of evidence and gaps within the literature that can influence amputation-related research, outcome assessment choices, and wellness activities. The purpose of this scoping review was to map the evidence regarding steps per day as a physical activity measure for PLL. Specific aims were to (1) identify research designs, (2) catalog population subgroups, (3) document steps per day measurement methods, and (4) provide descriptive data for steps per day in PLL.

METHODS

The MEDLINE, CINAHL, Embase, Web of Science, and AMED databases; and the Journal of Prosthetics and Orthotics archive were searched without language or time limits. Exclusion criteria included no PLL subjects, not peer-reviewed, and no direct step count measure. Inclusion criteria allowed any sample size, nonprosthetic use, and self-reported step count. As a scoping review, only descriptive statistics were compiled, and no methodologic quality assessment was performed.

RESULTS

Twenty-one articles using crossover (8), cohort (4), cross-section (8), and case-study (1) designs were included that reported accelerometer (19) or pedometer (2) data. Studies often mixed amputation etiologies (15/21) and most (13/21) excluded transfemoral amputations. Studies primarily examined people with transtibial amputations (81.2%) and people at independent community walking levels (Medicare functional classifications: K3 = 49.2%, K4 = 36.3%). All 21 studies had fewer than 100 participants, and overall included 515 subjects (343, 66.6% male), mean (SD) age 53.2 (22.1) years. Mean (SD) number of pooled steps per day for PLL was 5087 (2998): 5929 (3047) for transtibial amputations and 3553 (2030) for transfemoral amputations.

CONCLUSIONS

Most PLL have low activity levels compared with the 10,000 steps per day generally recommended or 6000 common in people with diabetes. Research with larger samples, defined subgroups, and data along the recovery continuum would enhance knowledge of physical activity level in PLL.

IMPACT

This scoping review has identified gaps in the research related to steps per day as a measure of physical activity in people with lower-limb loss to guide future research.

LAY SUMMARY

People with lower-limb loss take fewer steps per day than suggested for general health. Increasing steps per day may be a useful goal for this population, and this study is a first step in improving knowledge of physical activity levels in people with lower-limb loss.

Locomotor activities of individuals with lower-limb amputation

BACKGROUND

Ambulatory individuals with lower-limb amputation perform a variety of locomotor activities, but the step count distribution of these activities is unknown.

OBJECTIVE

To describe a novel method for activity monitoring and to use it to count steps taken while walking straight ahead on level ground, turning right and left, up and down stairs, and up and down ramps.

STUDY DESIGN

This is an observational study.

METHODS

A portable instrument to record leg motion was placed on or inside the prosthetic pylon of 10 individuals with unilateral transtibial amputations. Participants first walked a defined course in a hospital environment to train and validate a machine learning algorithm for classifying locomotor activity. Participants were then free to pursue their usual activities while data were continuously collected over 1-2 d.

RESULTS

Overall classification accuracy was 97.5% ± 1.5%. When participants were free to walk about their home, work, and community environments, 82.8% of all steps were in a straight line, 9.0% were turning steps, 4.8% were steps on stairs, and 3.6% were steps on ramps.

CONCLUSION

A novel activity monitoring method accurately classified the locomotion activities of individuals with lower-limb amputation. Nearly 1 in 5 of all steps taken involved turning or walking on stairs and ramps.

STEPFORWARD study: a randomised controlled feasibility trial of a self-aligning prosthetic ankle-foot for older patients with vascular-related amputations

OBJECTIVES

To determine the feasibility of conducting a full-scale randomised controlled trial (RCT) of the effectiveness and cost-effectiveness of a self-aligning prosthetic ankle-foot compared with a standard prosthetic ankle-foot.

DESIGN

Multicentre parallel group feasibility RCT.

SETTING

Five prosthetics centres in England recruiting from July 2018 to August 2019.

PARTICIPANTS

Adults aged ≥50 years with a vascular-related or non-traumatic transtibial amputation for 1 year or longer, categorised as having 'limited community mobility' and using a non-self-aligning ankle-foot.

INTERVENTION

Participants were randomised into one of two groups for 12 weeks: self-aligning prosthetic ankle-foot or existing non-self-aligning prosthetic ankle-foot.

OUTCOMES

Feasibility measures: recruitment, consent and retention rates; and completeness of questionnaire and clinical assessment datasets across multiple time points. Feasibility of collecting daily activity data with wearable technology and health resource use data with a bespoke questionnaire.

RESULTS

Fifty-five participants were randomised (61% of the target 90 participants): n=27 self-aligning ankle-foot group, n=28 non-self-aligning ankle-foot group. Fifty-one participants were included in the final analysis (71% of the target number of participants). The consent rate and retention at final follow-up were 86% and 93%, respectively. The average recruitment rate was 1.25 participants/site/month (95% CI 0.39 to 2.1). Completeness of questionnaires ranged from 89%-94%, and clinical assessments were 92%-95%, including the activity monitor data. The average completion rates for the EQ-5D-5L and bespoke resource use questionnaire were 93% and 63%, respectively.

CONCLUSIONS

This feasibility trial recruited and retained participants who were categorised as having 'limited community mobility' following a transtibial amputation. The high retention rate of 93% indicated the trial was acceptable to participants and feasible to deliver as a full-scale RCT. The findings support a future, fully powered evaluation of the effectiveness and cost-effectiveness of a self-aligning prosthetic ankle-foot compared with a standard non-self-aligning version with some adjustments to the trial design and delivery.

TRIAL REGISTRATION NUMBER

ISRCTN15043643.

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.

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.

Self-Efficacy and Social Support are Associated with Disability for Ambulatory Prosthesis Users After Lower-Limb Amputation

BACKGROUND

Interventions targeting psychosocial factors may improve rehabilitation outcomes for prosthesis users after lower-limb amputation (LLA), but there is a need to identify targeted factors for minimizing disability.

OBJECTIVE

To identify psychosocial factors related to disability for prosthesis users after LLA in middle age or later.

DESIGN

Cross-sectional study.

SETTING

General community.

PARTICIPANTS

Participants with LLA (N = 122) were included in this cross-sectional study if their most recent LLA was at least 1 year prior, they were ambulating independently with a prosthesis, and they were between 45 and 88 years old.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Disability, the primary outcome, was measured using the World Health Organization Disability Assessment Schedule 2.0 (WHODAS). Candidate psychosocial variables included self-efficacy, social support, and motivation, measured using the Self-Efficacy of Managing Chronic Disease questionnaire (SEMCD), Multidimensional Scale of Perceived Social Support questionnaire (MSPSS), and modified contemplation ladder (mCL), respectively. The hypothesis was that greater self-efficacy, social support, and motivation would be associated with lower disability when controlling for covariates.

RESULTS

The covariate model, including etiology, age, sex, U.S. military veteran status, LLA characteristics, time since LLA, medical complexity, and perceived functional capacity, explained 66.1% of disability variability (WHODAS 2.0). Backward elimination of candidate psychosocial variables stopped after removal of motivation (P = .10), with self-efficacy (P < .001) and social support (P = .002) variables remaining in the final model. The final model fit was statistically improved (P < .001) and explained an additional 6.1% of disability variability when compared to the covariate model.

CONCLUSIONS

Greater self-efficacy and social support are related to lower disability after LLA. Findings suggest there may be a role for interventions targeting increased physical function, self-efficacy, and social support for ambulatory prosthesis users after LLA in middle age or later, especially when complicated by multiple chronic conditions.