Minimally invasive A2 flexor tendon pulley and biomechanical comparison with two accepted techniques

Abstract

The increasing popularity of rock climbing and its associated injury of closed traumatic pulley A2 rupture has sparked investigator interest in pulley biomechanics. Biomechanically, the A2 and A4 pulleys are important for preventing bowstringing of the flexor tendon upon digital flexion. The literature is replete with reparative techniques for A2 pulley rupture. These techniques include direct fibrous tissue repair, as well as the use of palmaris longus autograft for single- and double-loop reconstruction. Through a previously undescribed minimally invasive double-anchor technique, we used palmaris longus tendon and 2-mm bioabsorbable suture anchors to reconstruct the A2 pulley at its anatomical location in a cadaver model. Then the ultimate load to failure of this reconstruction was tested against 2 known reconstructive techniques, namely, single-loop and double-loop palmaris repair. There was no significant difference between the strength of the previously described single-loop technique and our novel double-anchor technique. Furthermore, our minimally invasive repair obviated the need for the circumferential dissection and soft tissue trauma associated with the single- and double-loop repairs.