Effect of the Steindler procedure on the median nerve branches to the medial epicondylar muscles.

Usually the median nerve gives off six branches to the muscles arising from the medial epicondyle, which could be tightened during Steindler's procedure. We studied these branches before and after Steindler's procedure in 20 fresh cadavers and observed a considerable variation in the origin of the branches. The muscular branches arising from the median nerve did not seem to limit the mobilization of the medial epicondyle when performing Steindler's transfer. The limitation of the flexion observed after Steindler's procedure was mainly related to the tension of the transferred forearm flexor muscles. The variability of the origin of the branch to the flexor digitorum superficialis muscle could explain a lesion of this branch when Steindler's procedure is carried out with Brunelli's modification. The lateral transfer and the anterior transfer on to the humeral shaft did not influence the limitation of elbow flexion or result in tightness in any nerve branch to the transferred muscles.