Effect of muscle tension during tendon transfer on sarcomerogenesis in a rabbit model

Sarcomere number change was investigated in an animal model of tendon trans fer. In 9 adult New Zealand white rabbits, the flexor digitorum longus musc le was cut distally and transferred and woven into the tibialis anterior te ndon. Ankles were then immobilized for 3 weeks in 75 degrees flexion. Trans ferred flexor digitorum longus muscles were harvested and complete architec tural analysis was performed. Sarcomere lengths were measured using laser d iffraction. Serial sarcomere number in transferred flexor digitorum longus fibers was a strong function of the sarcomere length at the time of transfe r. A highly significant negative correlation between these 2 parameters was approximated by a linear relationship. Based on this finding, we conclude that serial sarcomere number is significantly affected by the degree of str etch during the transfer itself. This could easily compromise the purpose o f surgical tendon transfer by reducing the procedure to little more than a tenodesis, Copyright (C) 2000 by the American Society for Surgery of the Ha nd.