Anatomical considerations of fascial release in ulnar nerve transposition: a concept revisited.

OBJECT: Surgical transposition of the ulnar nerve to alleviate entrapment may cause otherwise normal structures to become new sources of nerve compression. Recurrent or persistent neuropathy after anterior transposition is commonly attributable to a new distal compression. The authors sought to clarify the anatomical relationship of the ulnar nerve to the common aponeurosis of the humeral head of the flexor carpi ulnaris (FCU) and flexor digitorum superficialis (FDS) muscles following anterior transposition of the nerve. METHODS: The intermuscular septa of the proximal forearm were explored in 26 fresh cadaveric specimens. The fibrous septa and common aponeurotic insertions of the flexor-pronator muscle mass were evaluated in relation to the ulnar nerve, with particular attention to the effect of transposition upon the nerve in this region. RESULTS: An intermuscular aponeurosis associated with the FCU and FDS muscles was present in all specimens. Transposition consistently resulted in angulation of the nerve during elbow flexion when this fascial septum was not released. The proximal site at which the nerve began to traverse this fascial structure was found to be an average of 3.9 cm (SD 0.7 cm) from the medial epicondyle. CONCLUSIONS: The common aponeurosis encountered between the FDS and FCU muscles represents a potential site of posttransposition entrapment, which may account for a subset of failed anterior transpositions. Exploration of this region with release of this structure is recommended to provide an unconstrained distal course for a transposed ulnar nerve.

Reconstruction of posterior interosseous nerve injury following biceps tendon repair: case report and cadaveric study.

Surgical repair of distal biceps tendon rupture is a technically challenging procedure that has the potential for devastating and permanently disabling complications. We report two cases of posterior interosseous nerve (PIN) injury following successful biceps tendon repair utilizing both the single-incision and two-incision approaches. We also describe our technique of posterior interosseous nerve repair using a medial antebrachial cutaneous nerve graft (MABC) and a new approach to the terminal branches of the posterior interosseous nerve that makes this reconstruction possible. Finally, we advocate consideration for identification of the posterior interosseous nerve prior to reattachment of the biceps tendon to the radial tuberosity.