Feasibility of repeated session error-augmentation gait training for people with nontraumatic transtibial amputation.

BACKGROUND: Spatiotemporal gait asymmetries are a persistent problem for people with non-traumatic lower-limb amputation. To date, there is limited knowledge of multi-session gait training interventions targeting step length symmetry after non-traumatic amputation. OBJECTIVE: The objective was to evaluate the feasibility and efficacy of an eight-session, treadmill-based error-augmentation gait training (EAT) protocol to improve spatiotemporal gait asymmetry in people with non-traumatic transtibial amputation (TTA). STUDY DESIGN: Pre-post, single group. Methods: The EAT protocol involved eight training sessions (twice per week, four weeks) of supervised split-belt treadmill walking with asymmetrical belt speeds for five, three-minute sets each session. Step length symmetry during overground walking at a self-selected gait speed was assessed prior to, weekly, and one-week after the EAT protocol. Feasibility outcomes included protocol fidelity, safety, participant acceptability, and efficacy. RESULTS: Seven of the eight participants (87.5%) completed the intervention at the prescribed dose. One participant developed a skin blister on their residual limb, which was possibly related to the intervention. No falls, musculoskeletal injuries, or increases in pain occurred. Participants rated EAT as acceptable based on scores on the Intrinsic Motivation Inventory - Interest/Enjoyment subscale (6.6 ± 0.5; mean ± SD). Average between-limb step length Normalized Symmetry Index improved (was reduced) one-week following EAT (2.41 ± 6.6) compared to baseline (5.47 ± 4.91) indicating a moderate effect size (d=0.53). CONCLUSIONS: An eight session EAT program delivered over four weeks using a split-belt treadmill is feasible for people with unilateral non-traumatic TTA and may reduce step length asymmetry up to a week after intervention.

Error-Manipulation Gait Training for Veterans With Nontraumatic Lower Limb Amputation: A Randomized Controlled Trial Protocol.

OBJECTIVE: he purpose of this study will be to determine the efficacy of error-manipulation gait training (error-augmentation or error-correction) to improve step length symmetry and secondary health outcomes in veterans with unilateral nontraumatic transtibial amputation (TTA). METHODS: This will be a 3-arm, parallel, assessor-blinded, randomized controlled trial, with baseline, postintervention, and 3-month follow-up assessments in a VA Geriatric Research Education and Clinical Center. Participants are 54 US military veterans ranging in age from 50 to 85 years with a unilateral transtibial nontraumatic amputation. Participants will be randomized into 1 of 3 groups: error-augmentation training (EAT), error-correction training (ECT), or supervised walking (CTL). Each group will complete 8 split-belt treadmill walking training sessions of 25 minutes each over 4 weeks. The EAT group will walk with belts moving at asymmetrical speeds. The ECT group will walk to the cadence of a metronome and the split belts moving at symmetrical speeds. The CTL group will walk with symmetrical belt speeds and without feedback. Step length symmetry is the primary outcome and will be assessed using an asymmetry index during overground walking. Secondary outcomes include lower extremity joint work during treadmill walking, 6-Minute Walk Test performance, daily step count, participant-perceived disability, and residual-limb integumentary health. Outcomes will be assessed at preintervention, 1-week postintervention (primary endpoint), and 13 weeks postintervention. IMPACT: This study protocol focuses on an understudied area of rehabilitation for patients with nontraumatic unilateral TTA who have high levels of spatiotemporal gait asymmetry and mobility impairment. The results of this study will inform future implementation of clinical gait training interventions to improve spatiotemporal gait symmetry and long-term health and disability outcomes in patients with nontraumatic unilateral TTA.

Falls After Dysvascular Transtibial Amputation: A Secondary Analysis of Falling Characteristics and Reduced Physical Performance.

INTRODUCTION: Over half of all people with lower limb amputation (LLA) experience at least one fall annually. Furthermore, the majority of LLAs result from dysvascular health complications, contributing to balance deficits. However, fall-related research specific to dysvascular LLA remains limited. OBJECTIVE: To characterize falls among adults with dysvascular LLA, using an existing Fall-Type Classification Framework and to describe the functional characteristics of participants across the framework categories. DESIGN: Secondary data analysis from two randomized controlled trials. SETTING: Outpatient setting. PARTICIPANTS: People (n = 69) 6 months to 5 years from dysvascular lower extremity amputation, who were ≥50 years of age and independently ambulatory using a prosthesis. INTERVENTION: None. OUTCOME: Descriptions of self-reported falls were collected on a weekly basis for 12 weeks, and analyzed using an existing Fall-Type Classification Framework. Fall frequencies, estimated count, and estimated proportions were compared across all framework categories, with 95% confidence intervals. Functional measures (Timed Up and Go, Two Minute Walk, Five Meter Walk, and average step count) were collected, and averages for each participant who experienced a fall were calculated. RESULTS: Thirty participants (43.5%) reported 42 falls within 12 weeks. A variety of fall types were described. Incidence of falls was highest for intrinsic destabilization sources, from incorrect weight shift patterns during transfer activities. CONCLUSION: Patients with dysvascular LLAs experience a variety of fall types. The high frequency of intrinsically sourced, incorrect weight-shift falls during transfer activities emphasizes the need to focus rehabilitation efforts on improving postural control in patients with dysvascular LLAs during activities such as reaching, turning, and transferring.

Step length symmetry adaptation to split-belt treadmill walking after acquired non-traumatic transtibial amputation.

BACKGROUND: Between-limb step length asymmetry is common following transtibial amputation (TTA) and contributes to negative health consequences. There are limited evidence-based interventions targeting reduced gait asymmetry for people with TTA. Split-belt treadmill walking with asymmetrical belt speeds has successfully reduced gait asymmetry in other patient populations. However, individuals with non-traumatic TTA have critical health-related impairments that may influence the ability to respond to split-belt treadmill walking. RESEARCH QUESTION: Do people with acquired, non-traumatic TTA adapt and retain a more symmetrical gait pattern in response to split-belt treadmill walking? METHODS: Step length asymmetry was measured during split-belt treadmill walking. Eight participants walked under two alternating belt speed conditions: symmetrical (3 sets; Baseline, TIED1, TIED2) and asymmetrical belt speeds (5 sets; SPLIT1-5). One-way repeated-measures ANOVA with post-hoc Tukey's HSD tests were used to assess adaptation and short-term retention of step length symmetry. Adaptation was assessed as the level of asymmetry during TIED walking following repeated exposure to SPLIT walking. Retention was measured as the change in level of asymmetry during each set of SPLIT walking. RESULTS: Significant adaptation to split-belt walking was observed from late Baseline to early TIED1 and early TIED2. Between-limb step length asymmetry decreased from late Baseline (5.3 ±â€¯3.4) to early TIED1 (-9.4 ±â€¯3.6) and this change was sustained between early TIED1 and early TIED2 (-11.2 ±â€¯3.1) (ANOVA F = 73.043, p < .001). Adaptations were retained as step length asymmetry decreased from early SPLIT1 (48.5 ±â€¯5.3) to early SPLIT3 (31.4 ±â€¯3.5) to early SPLIT5 (23.9 ±â€¯5.1) (ANOVA F = 35.284, p < .001). SIGNIFICANCE: Individuals with non-traumatic TTA are capable of gait adaptation to split-belt walking and short-term retention of adaptations after removal of the asymmetrical belt speeds. Adaptability of step length symmetry is possible without modification to the prosthetic limb. Split-belt walking should be tested as a potential intervention to help people with acquired, non-traumatic TTA increase between-limb step symmetry.

Qualitative analysis of resilience characteristics of people with unilateral transtibial amputation.

BACKGROUND: Resilience characteristics are a significant factor in the highly variable rehabilitation outcomes for people in middle age or later with transtibial amputation. OBJECTIVE: The purpose of this study was to describe resilience characteristics meaningful to people with transtibial amputation in middle age or later, who use a prosthesis. METHODS: Semi-structured interviews were conducted, audio recorded, and transcribed with eighteen participants. Interview transcripts were coded and analyzed using a directed content analysis approach, guided by Charney's theory of resilience and Connor-Davidson Resilience Scale scores. RESULTS: Five main resilience characteristics (themes) were identified: coping skills, cognitive flexibility, optimism, skill for facing fear, and social support. Participants with higher resilience scores generally described effective use of coping skills, cognitive flexibility, optimism, skills in facing fears, and social support to attain meaningful goals. In contrast, participants with lower resilience scores discussed passive coping strategies, cognitive rigidity, general pessimism, avoidance of activities due to fear, or social support limitations. CONCLUSION: Coping skills, cognitive flexibility, optimism, skills for facing fear, and social support were identified as meaningful resilience characteristics for people with transtibial amputation in middle age or later. These characteristics can be targeted and enhanced using resilience interventions. Future research should consider these characteristics when designing and testing rehabilitation focused resilience interventions for people with TTA.

Prosthetic fitting after rotationplasty of the knee.

OBJECTIVE: The objectives of this study were to describe the authors' experience with the timeline for prosthetic fitting after rotationplasty of the knee and to determine factors that may be associated with earlier prosthetic fitting. DESIGN: The authors conducted a retrospective observational study of 12 patients who underwent rotationplasty of the knee and received prosthetic care at this institution. All patients had oncologic causes for surgery. RESULTS: The median age at amputation was 10 yrs. The overall survival rate was 92%. Five patients received a preliminary bypass prosthesis. All 12 patients were successfully fitted with a definitive prosthesis. Three patients were fitted within 90 days; two of these three patients did not require chemotherapy. The median time for definitive prosthetic fitting in the ten patients requiring chemotherapy was 230.5 days (range, 85-425 days). Nine patients had documentation supporting a return to sport/premorbid physical recreational activities. CONCLUSIONS: In the authors' experience, chemotherapy was associated with delayed definitive prosthetic fitting. Typically, the patients who required rotationplasty for cancer completed fitting with a definitive prosthesis in 6 mos. The findings of this study validate previous reports and confirm that most rotationplasty patients have excellent outcomes with return to premorbid physical activities.

Motor unit potential induced repetitive discharges (MIRDs): description of an unusual iterative discharge.

INTRODUCTION: Repetitive discharges may be recorded during nerve conduction studies (NCS) or during needle electromyography in a muscle at rest. Repetitive discharges that occur during voluntary activation and are time-locked to voluntary motor unit potentials (MUP) have not been described. METHODS: Retrospective review of motor unit potential induced repetitive discharges (MIRDs) identified in the EMG laboratory. Characteristics of each MIRD, patient demographics, other EMG findings in the same muscle, and electrophysiological diagnosis were analyzed. RESULTS: MIRDs were observed in 15 patients. The morphology and number of spikes and duration of MIRDs varied. The discharges fired at rates of 50-200 Hz. All but 2 patients had EMG findings of a chronic neurogenic disorder. CONCLUSIONS: MIRDs are rare iterative discharges time-locked to a voluntary MUP. The pathophysiology of MIRDs is unclear, but their presence may indicate a chronic neurogenic process.