Comparison of the biomedical motions and forces involved in high-profile versus low-profile dynamic splinting

The purpose of this study was to compare the biomechanical motions and forces generated with a commercially available high-profile splint with those generated with a commercially available low-profile splint outrigger. The efficiency of the splints for maintaining index-digit supination during active flexion with the digit placed in slings generating a supination force couple was analyzed. The forces necessary to initiate and to maintain finger flexion were studied for each device using force transducers. Motion and force analyses were performed in the Biomechanics Evaluation Laboratory at Michigan State University. Synchronized video cameras recorded movement of anatomic landmarks, which were located by way of spherical retroreflective targets. Software programs calculated joint angles and digit movement. The results indicated that the high-profile splint held the digit in greater supination during flexion than did the low-profile splint. Also, the high-profile splint required less force during active flexion to initiate and to maintain motion than did the low-profile splint.