The role of exercise testing in predicting successful ambulation with a lower extremity prosthesis: a systematic literature review and clinical practice guideline.

BACKGROUND: Growing discontent with the k-level system for functional classification of patients with limb loss and movement of healthcare toward evidence-based practice has resulted in the need for alternative forms of functional classification and development of clinical practice guidelines to improve access to quality prosthetic interventions. The purpose of this project was to develop and present a clinical practice recommendation for exercise testing in prosthetic patient care based on the results and synthesis of a systematic literature review. METHODS: Database searches of PubMed, Google Scholar, Web of Science, and Cochrane were conducted and articles reviewed. Of the potential 1386 articles 10 met the criteria for inclusion. These articles were assessed using the critical appraisal tool of the United Kingdom National Service Framework for Long-Term Conditions. Of the 10 included articles eight were of high, one of medium, and one of low, quality. Data from these articles were synthesized into 6 empirical evidence statements, all qualifying for research grade A. These statements were used to develop the proposed clinical practice guideline. RESULTS: While the results of this systematic review were not able to support the direct connection between cardiorespiratory performance and K-levels, the literature did support the ability of exercise testing results to predict successful prosthetic ambulation in some demographics. Both continuous maximum-intensity single lower extremity ergometer propelled by a sound limb and intermittent submaximal upper extremity ergometer protocols were found to be viable evaluation tools of cardiorespiratory fitness and function in the target population. CONCLUSION: The ability to sustain an exercise intensity of ≥50% of a predicted VO2max value in single leg cycle ergometry testing and achievement of a sustained workload of 30 W in upper extremity ergometry testing were found to be the strongest correlates to successful ambulation with a prosthesis. VO2 values were found to increase in amputee subjects following a 6-week exercise program. These synthesized results of the systematic literature review regarding exercise testing in patients with loss of a lower extremity were used to develop and a present a clinical treatment pathway.

Energy costs and performance of transfemoral amputees and non-amputees during walking and running: A pilot study.

BACKGROUND: Limited information is available concerning the effects of prosthetic foot components on energy costs and ambulatory performance for transfemoral amputees. OBJECTIVES: Compare energy costs (VO2; gait economy) and ambulatory performance (self-selected walking speeds, self-selected running speeds, peak running speeds) differences during walking and running for transfemoral amputees and matched, non-amputee runners. STUDY DESIGN: Repeated measures. METHODS: Transfemoral amputees were accommodated and tested with three prosthetic feet: conventional foot, solid-ankle cushioned heel (SACH); energy storing and return foot, Renegade; and running-specific energy storing and return foot, Nitro. RESULTS: During walking, VO2 was similar between transfemoral amputees but was increased compared to controls. Self-selected walking speeds were slower for SACH compared to Renegade and Nitro. For transfemoral amputees, gait economy was decreased and self-selected walking speeds were slower compared to controls. During fixed running speeds, transfemoral amputees ran using Nitro, and VO2 was greater compared to controls. Transfemoral amputees ran at self-selected running speeds using Renegade and Nitro. Self-selected running speeds were slower for Renegade compared to Nitro. For transfemoral amputees, gait economy was decreased and self-selected running speeds were slower compared to controls. VO2 peak was similar between transfemoral amputees and controls, but controls achieved greater peak running speeds and % grade. CONCLUSION: Energy costs were greater and ambulatory performance was lower for transfemoral amputees compared to matched, non-amputee controls for all prosthetic foot conditions. Clinical relevance Both types of energy storing and return feet may improve walking performance for transfemoral amputees by providing faster self-selected walking speeds. For transfemoral amputees interested in performing vigorous running (exercise and running competition), clinicians should recommend a running-specific energy storing and return foot.

Functional performance differences between the Genium and C-Leg prosthetic knees and intact knees.

Microprocessor prosthetic knees (MPKs) have advanced technologically, offering new features to decrease impairment and activity limitations for persons with transfemoral amputation (TFA). The Genium knee is functionally untested, and functional differences between it and intact knees are unknown. This study sought to determine whether Genium use improves functional performance compared with the C-Leg. A randomized experimental crossover design was used, with a cross-section of five nonamputee controls for comparison to normal. Twenty community-ambulating persons with TFA were trained and tested for accommodation with study components. All subjects (n = 25) were assessed using the Continuous-Scale Physical Functional Performance-10 (CS-PFP10) assessment. Subjects with TFA used both MPK systems. Genium use improved upper-body flexibility, balance, and endurance domain scores (7.0%-8.4%, p

BIOENERGETIC DIFFERENCES DURING WALKING AND RUNNING IN TRANSFEMORAL AMPUTEE RUNNERS USING ARTICULATING AND NON-ARTICULATING KNEE PROSTHESES.

Transfemoral amputation (TFA) patients require considerably more energy to walk and run than non-amputees. The purpose of this study was to examine potential bioenergetic differences (oxygen uptake (VO2), heart rate (HR), and ratings of perceived exertion (RPE)) for TFA patients utilizing a conventional running prosthesis with an articulating knee mechanism versus a running prosthesis with a non-articulating knee joint. Four trained TFA runners (n = 4) were accommodated to and tested with both conditions. VO2 and HR were significantly lower (p ≤ 0.05) in five of eight fixed walking and running speeds for the prosthesis with an articulating knee mechanism. TFA demonstrated a trend for lower RPE at six of eight walking speeds using the prosthesis with the articulated knee condition. A trend was observed for self-selected walking speed, self-selected running speed, and maximal speed to be faster for TFA subjects using the prosthesis with the articulated knee condition. Finally, all four TFA participants subjectively preferred running with the prosthesis with the articulated knee condition. These findings suggest that, for trained TFA runners, a running prosthesis with an articulating knee prosthesis reduces ambulatory energy costs and enhances subjective perceptive measures compared to using a non-articulating knee prosthesis.

CONCURRENT VALIDITY OF THE CONTINUOUS SCALE-PHYSICAL FUNCTIONAL PEFORMANCE-10 (CS-PFP-10) TEST IN TRANSFEMORAL AMPUTEES.

The Continuous Scale-Physical Functional Performance-10 (CS-PFP-10) test consists of 10 standardized daily living tasks that evaluate overall physical functional performance and performance in five individual functional domains: upper body strength (UBS), upper body flexibility (UBF), lower body strength (LBS), balance and coordination (BAL), and endurance (END). This study sought to determine the concurrent validity of the CS-PFP-10 test and its functional domains that involve the lower extremities (LBS, BAL, or END) in comparison to measures that have established validity for use in persons with transfemoral amputation (TFA). Ten TFA patients functioning at K3 or higher (Medicare Functional Classification Level) completed the study. Participants were assessed performing the CS-PFP-10, Amputee Mobility Predictor (AMP), 75 m self-selected walking speed (75 m SSWS) test, timed down stair walking (DN stair time), and the limits of stability (LOS) balance test. Concurrent validity was assessed using correlation analysis. The AMP, 75 m SSWS, LOS, and the DN stair time tests were strongly correlated (r = ± 0.76 to 0.86) with their paired CS-PFP-10 domain score (LBS, BAL, or END) and CS-PFP-10 total score. These findings indicate that the lower limb and balance domains of the CS-PFP-10 are valid measures to assess the physical functional performance of TFA patients.

PSYCHOMETRIC EVALUATION OF THE HILL ASSESSMENT INDEX (HAI) AND STAIR ASSESSMENT INDEX (SAI) IN HIGH-FUNCTIONING TRANSFEMORAL AMPUTEES.

The hill assessment index (HAI) and stair assessment index (SAI) were developed to objectively evaluate ramp and stair gait. This study's purpose was to determine the validity and reliability of these tests in a sample of persons with unilateral transfemoral amputation (TFA) using microprocessor prosthetic knee systems. All subjects were fit with a microprocessor knee system. After accommodation, subjects performed three trials ascending and descending a 5° ramp and a flight of stairs while being recorded on video. Sensitivity and specificity for the HAI was calculated against degree of asymmetry in step length using Dartfish video analysis software. Reliability was assessed using intraclass correlational coefficients calculated using Spearman's Rho (rs). A priori significance level was set at p ≤ 0.05. Twenty (n = 20) individuals with TFA completed the study protocol. Sensitivity and specificity of the HAI were calculated at 88.0% and 75.0% during ascending conditions and 94.0% and 67.0% during descending conditions, respectively. Significant correlations for the HAI included rs = 0.87 and rs = 0.73 within raters uphill and downhill, respectively. Corresponding coefficients of rs = 0.80 and rs = 0.67 were calculated between raters. For the SAI, significant correlations included rs = 1.00 for both comparisons within raters and in the comparison between raters in the ascending condition. A correlation of rs = 0.89 was calculated for the between-rater comparison in the descending condition. The HAI showed moderate to excellent sensitivity and specificity but good to adequate reliability. The SAI showed excellent to good reliability.

Correlations between residual limb length and joint moments during sitting and standing movements in transfemoral amputees.

BACKGROUND AND AIM: Longer residual limb lengths provide an increased lever arm. Longer residual limbs may produce increased joint moments; the two may be correlated. These correlations have not been evaluated in transfemoral amputees during transitional movements. Correlations between residual limb length and involved side joint moment could contribute to justification supporting maximal residual limb length preservation. This study investigated possible correlations between hip or knee moment and residual limb length. TECHNIQUE: Hip and knee joint moments were determined while 21 transfemoral amputees performed sitting and standing movements and then evaluated for correlation with residual limb length. DISCUSSION: Residual limb length was not correlated with either knee or involved side hip moments during sit to stand or stand to sit. Conversely, weak inverse correlations (p < 0.05) existed between sound hip moment magnitude and residual limb length. These correlations suggest that in community ambulating transfemoral amputees, longer residual limb length could decrease sound hip kinetic burden during transitional movement. Beyond correlations between residual limb length and sound hip transitional movement kinetics, there are other considerations in determining residual limb length during amputation. CLINICAL RELEVANCE: This study examines relationships between lower limb joint moments and residual limb length related to sit-to-stand and stand-to-sit activities. The results have implications for amputation surgery and rehabilitation.

Comparison of the metabolic demands of dance performance using three mobility devices for a dancer with spinal cord injury and an able-bodied dancer.

Mobility devices for dancers with physical mobility impairments have previously been limited to traditional manual or power wheelchairs. The hands-free torso-controlled mobility chair is a unique powered mobility device which allows greater freedom and expression of movement of the trunk and upper extremities. This study compared differences in energy expenditure during a standardized dance activity using three mobility devices: the hands-free torso-controlled mobility chair, a manual sports wheelchair with hand-arm control, and an electric power chair with hand-joystick control. An experienced dancer with C7 incomplete spinal cord injury (SCI) and an experienced able-bodied dancer were recruited for testing. Three measurement trials were obtained for each chair per subject. Oxygen uptake (VO2) and heart rate (HR) were measured continuously during the dance activity. Immediately following the dance activity, subjects rated perceived exertion. Significant differences (p ≤ 0.05) and similar linear patterns in VO2 and HR responses were observed between chairs for both dancers. When the hands-free mobility chair was used, the dance activity required a moderate level of energy expenditure compared to the manual sports chair or electric power chair for both dancers. Higher ratings of perceived exertion were observed in the manual chair compared to the other chairs for the dancer with SCI, but were similar between chairs for the able-bodied dancer. These results suggest that for a dancer with high-level SCI, the hands-free torso-controlled mobility chair may offer improved freedom and expressive movement possibilities and is an energy-efficient mobility device.

Ramp descent performance with the C-Leg and interrater reliability of the Hill Assessment Index.

BACKGROUND: Transfemoral amputees have decreased ability to descend ramps and hills. The Hill Assessment Index quantifies transfemoral amputee ramp performance, but interrater reliability has not been assessed. OBJECTIVES: To determine whether C-Leg use improves hill descent gait and evaluate the Hill Assessment Index's interrater reliability. METHODS: Twenty-one transfemoral amputees descended a ramp while timed and video recorded, using their nonmicroprocessor prosthetic knee. Subjects were fitted and accommodated with a C-Leg and retested. Test times were compared, and ramp performances were independently reviewed using the Hill Assessment Index by two raters. Hill Assessment Index scores were compared between knee conditions within raters for performance and between raters to assess the Hill Assessment Index's interrater reliability. RESULTS: Mean Hill Assessment Index scores were greater for C-Leg compared to nonmicroprocessor prosthetic knee for both raters. C-Leg resulted in faster ramp descent. Strong correlations resulted between raters on Hill Assessment Index scores for nonmicroprocessor prosthetic knee (intraclass correlation coefficient = 0.97) and C-Leg (intraclass correlation coefficient = 0.99). CONCLUSIONS: C-Leg improves Hill Assessment Index ramp descent performance and time. In descent quality, C-Leg offers the possibility of eliminating assistive device use and/or improving step length in the absence of an assistive device. C-Leg resulted in 23% gait speed increase during ramp descent. The Hill Assessment Index had very good interrater reliability but should be assessed for intrarater reliability, minimal detectable change, and validity.

Comparison of work rates, energy expenditure, and perceived exertion during a 1-h vacuuming task with a backpack vacuum cleaner and an upright vacuum cleaner.

The purpose of this study was to evaluate two types of industrial vacuum cleaners, in terms of cleaning rates, energy expenditure, and perceived exertion. Twelve industrial cleaners (six males and six females, age 28-39 yr) performed two 1-h vacuuming tasks with an upright vacuum cleaner (UVC) and a backpack vacuum cleaner (BPVC). Measures for oxygen uptake (VO2) and ratings of perceived exertion (RPE) were collected continuously during the 1-h vacuuming tasks. Cleaning rates for the UVC and BPVC were 7.23 and 14.98 m2min(-1), respectively. On a separate day subjects performed a maximal treadmill exercise test to determine their maximal aerobic capacity (peak VO2). Average absolute energy costs (in Metabolic equivalents), relative energy costs of the vacuum task compared to the subjects' maximal aerobic capacity (% peak VO2), and RPE responses for the 1-h vacuuming tasks were similar between vacuum cleaners, but % peak VO2 and RPE values differed between genders. These results indicate that the BPVC was more efficient than the UVC. With the BPVC, experienced workers vacuumed at a cleaning rate 2.07 times greater than the UVC and had similar levels of energy expenditure and perceived effort, compared to the slower cleaning rate with the UVC.