Functional evaluation of quadriplegic patients using a hand neuroprosthesis. The objective of this retrospective study was to compare the abilities of quadriplegic patients to complete activities of daily living with and without the use of a portable hand neuroprosthesis. The neuroprosthesis provided synthetic hand grasp through functional neuromuscular stimulation of paralyzed forearm and hand muscles. Data were obtained from telephone interviews, patient records, and videotapes. Twenty-two quadriplegic patients were included in the study; 15 were functional at a C5 spinal cord injury level and seven at a C6 level. The median success rate (ie, the percentage of patients who could complete each activity) across the ten activities was 89% with the hand neuroprosthesis but was only 49% without the hand neuroprosthesis. All patients could perform more tasks when the neuroprosthesis was used, although the relative improvement of C5 patients was larger than that of C6 patients. 