Flexor Carpi Radialis and Dorsal Intercarpal Complex Elongation After 3 Ligament Tenodesis.

Abstract

To improve the surgical procedure and rehabilitation after surgery, a better understanding of the biomechanical properties of the 3 ligament tenodesis (3LT) procedure is necessary. This study examined elongation in relation to flexion, and type of failure after 3LT using 10 anatomic specimens, each wrist undergoing 5 tests. At 80° flexion mean elongation of the flexor carpi radialis (FCR) tendon slip was 0.96 ± 0.38 mm. Mean elongation of the dorsal intercarpal complex (DIC) was 3.75 ± 0.91 mm at 80° flexion. Relative elongation at the FCR tendon slip was 4.1% and 33.4% at the DIC. In 2 tests (4%), sutures loosened at the proximal side of the DIC after 30° flexion. Ruptures of the radiotriquetral ligament, pull-outs of the bone anchor or FCR tendon ruptures were not observed. This experiment suggests that following 3LT, the most elongation occurs at the DIC. Since instances of failure were noted at the proximal aspect of the DIC, if early active motion protocols are used, it is recommended to initiate wrist flexion with a limitation to 30° wrist flexion.