Upper extremity motor training of a subject with initially motor complete chronic high tetraplegia using constraint-induced biofeedback therapy

Abstract

The purpose of this case study was to determine if a subject with chronic high tetraplegia (C3 AIS A) could learn to use an initially paralyzed upper extremity on the basis of training procedures alone. Initially, an AIS examination revealed no purposive movement below the neck other than minimal shoulder movement. Training was carried out weekly over 39 months. Training began based on electromyographic biofeedback; the electrical activity of a muscle (biceps or triceps) was displayed visually on a computer monitor and the subject was encouraged to progressively increase the magnitude of the response in small increments on a trial-by-trial basis (i.e., shaping). When small, overt movements began to appear; these were, in turn, shaped so that their excursion progressively increased. Training then progressed to enable lifting the arm with the aid of the counterweight of a Swedish Help Arm. Mean movement excursions in the best session were: internal rotation 52.5 cm; external rotation 26.9 cm; shoulder extension 22.1 cm; shoulder flexion 15.2 cm; pronation/supination 120°; extension of index finger (D2) 2.5 cm. Movements were initially saltatory, becoming smoother over time. With the Swedish Help Arm, the subject was able to lift her hand an average of 24.3 cm in the best session with 0.7 kg counterweight acting at the wrist (1.9 J of work). Results suggest in preliminary fashion the effectiveness of this approach for improving upper extremity function after motor complete high tetraplegia. Thus, future studies are warranted. Possible mechanisms are discussed.