Work of flexion after flexor tendon repair according to the placement of sutures

Tendon repairs comparing dorsal or volar placement of sutures were done on 36 flexor profundus tendons from 9 canine cadaveric paws. Three suture techniques were used. Work of flexion as a measure of resistance to tendon gliding was measured in the following groups: Groups 1 and 2: 4-strand Savage technique with 5-0 core suture, dorsal or volar placement; Groups 3 and 4: 4-strand Savage technique with 4-0 core suture, dorsal or volar placement; and Groups 5 and 6: tendon splint technique, dorsal or volar placement. The increase in work of flexion values were 11.3%, 14.1%, 12.2%, 37%, 20.5%, and 92.7% for Groups 1 through 6, respectively. The increase in work of flexion value in Group 4 was significantly greater than that in Group 3, and the value in Group 6 was significantly greater than Group 5. These data suggest that the work of flexion after tendon repair was influenced by the location of the suture material; volar location of suture material significantly increased the work of flexion value.