Flexor tendon-pulley interaction after pulley reconstruction: a biomechanical study in a human model in vitro

Ten cadaver digits were used to evaluate excursion resistance between a tendon and pulley after completing 4 methods of pulley reconstruction (Bunnell's, Kleinert's, Lister's, and Karev's techniques). Five tissues (palmaris longus tendon, extensor digitorum tendon, flexor digitorum superficialis tendon, extensor retinaculum, and volar plate) were used to reconstruct the A2 pulley. Intrasynovial tissue sources (extensor retinaculum, volar plate, and flexor digitorum superficialis tendon) produced less excursion resistance than extrasynovial tissue sources (extensor digitorum tendon and palmaris longus tendon). The models using the extensor retinaculum and volar plate as reconstructive materials produced less excursion resistance than the normal A2 pulley, whereas the models using the palmaris longus tendon produced the highest excursion resistance. Bunnell's technique of pulley reconstruction produced less excursion resistance than Kleinert's technique with all 3 tissues tested. The results of the in vitro study of excursion resistance between the tendon and reconstructed pulley demonstrated that Lister's technique of pulley reconstruction using the extensor retinaculum produced the least resistance to tendon gliding.