Comparative mechanical analysis of dorsal versus palmar placement of core suture for flexor tendon repairs

This study was designed to evaluate the effect of core suture placement in the coronal plane on the tensile strength of flexor tendon repairs. We compared the tensile strength of modified Kessler core sutures placed in the palmar versus the dorsal side of matched-lacerated human cadaver flexor digitorum profundus tendons tested in vitro under static loading. We also compared the relative strengths of the dorsal and palmar portions of the flexor digitorum tendons. The mean failure load of a dorsal-side modified Kessler suture was 26.5% greater than that of a palmar-side modified Kessler suture. The mean strength of the dorsal half of the flexor digitorum tendons was 58.3% greater than that of the palmar half of the flexor digitorum tendons. Our data demonstrate that the dorsal tendon can sustain greater loads-to-failure than the palmar tendon. This suggests that there are biomechanical advantages to dorsal as opposed to palmar placement of the core suture in clinical tendon repair.