Lower extremity functional electrical stimulation cycling promotes physical and functional recovery in chronic spinal cord injury

Abstract

Objective: To examine the effect of long-term lower extremity functional electrical stimulation (FES) cycling on the physical integrity and functional recovery in people with chronic spinal cord injury (SCI).

Design: Retrospective cohort, mean follow-up 29.1 months, and cross-sectional evaluation.

Setting: Washington University Spinal Cord Injury Neurorehabilitation Center, referral center.

Participants: Twenty-five people with chronic SCI who received FES during cycling were matched by age, gender, injury level, and severity, and duration of injury to 20 people with SCI who received range of motion and stretching.

Intervention: Lower extremity FES during cycling as part of an activity-based restorative treatment regimen.

Main outcome measure: Change in neurological function: motor, sensory, and combined motor-sensory scores (CMSS) assessed by the American Spinal Injury Association Impairment scale. Response was defined as ≥ 1 point improvement.

Results: FES was associated with an 80% CMSS responder rate compared to 40% in controls. An average 9.6 CMSS point loss among controls was offset by an average 20-point gain among FES subjects. Quadriceps muscle mass was on average 36% higher and intra/inter-muscular fat 44% lower, in the FES group. Hamstring and quadriceps muscle strength was 30 and 35% greater, respectively, in the FES group. Quality of life and daily function measures were significantly higher in FES group.

Conclusion: FES during cycling in chronic SCI may provide substantial physical integrity benefits, including enhanced neurological and functional performance, increased muscle size and force-generation potential, reduced spasticity, and improved quality of life.

Figures

Figure 1

(A) Quantitative volume measurements of component thigh muscles and sternocleidomastoid muscle (internal control). Data represent the mean volume with SE bars (n = 20 and 25, controls and FES subjects, respectively) (*P < 0.001, **P < 0.01). (B) Peak resistance torque (spasticity) in hamstrings during right knee extension showing a decreasing amount of spasticity with increasing velocity in the FES group compared to controls.

Figure 2

(A) Health-related quality of life assessed by the Medical Outcomes Study 36-Item Short Form Survey (SF-36) among FES and control group after mean 29.1 month follow-up. Data represents mean scores with SE bars (*P < 0.05). (B) Comparison of Functional Independent Measures (FIM) scores after mean 29.1-month follow-up showing improvements in quality of life and functional measures in selective FIM domains with FES use. Data represents mean scores with SE bars. *P ≤ 0.001; **P < 0.05.