Background Exoskeletons may provide quadriceps augmentation to patients with a torn or permanently weak extensor mechanism. Pneumatic exoskeletons utilize pressurized gas to improve gait, but their use and biomechanical impact have not been well described. Methods A lightweight pneumatic robotic wearable device was piloted in a clinical gait case report study using four different conditions—no devices, walking stick, inactive brace, and active brace. Walking speed, step length, step time, step width, and hip and knee flexion/extension angles were assessed while walking on a flat, declined, and inclined surface. Results Walking speed on a flat surface with the active brace (0.41 ± 0.03 m/s) was 45% faster than walking with no devices (0.28 ± 0.04 m/s). Knee flexion at initial contact (19.0 ° ± 0.2 ° ) and peak knee flexion during stance (19.0 ° ± 0.2 ° ) were greater with the active brace than with no device (−2.3 ° ± 1.7 ° and −1.3 ° ± 0.7 ° , respectively). The active brace (0.89 ± 0.07 s) was associated with a 17% shorter step time during incline walking compared to no devices (1.06 ± 0.09 s). It was also associated with a 62% longer step length during decline walking compared to no devices (0.27 ± 0.04 vs. 0.17 ± 0.03 m). Conclusion In this case report, a pneumatic robotic knee wearable device improved quadriceps function and increased walking speed while freeing one arm to perform other tasks. A training program that optimizes function and comfort may improve device adoption as patients may need time to become acquainted with external torque delivery to the limb.
Lee et al. (Thu,) studied this question.