Anteromedial elbow arthroscopy portals in patients with prior ulnar nerve transposition or subluxation.

Purpose: The purpose of this study was to document management strategies and complications relating to the use of anteromedial portals for elbow arthroscopy in a series of patients with subluxating or previously transposed ulnar nerves.

Methods: A review of 913 elbow arthroscopies showed that 59 elbows with a subluxating or previously transposed ulnar nerve required anterior compartment arthroscopic surgery. The patients with subluxating nerves had proximal anteromedial portals established by reducing and holding the nerve behind the epicondyle with a thumb while establishing or entering the portal. In cases of prior nerve transposition, the following techniques were used if, by palpation, localization of the ulnar nerve was considered to be (1) unequivocal, (2) equivocal, or (3) impossible: In group 1 (unequivocal) the proximal anteromedial portal was established in the normal antegrade fashion. In group 2 (equivocal) a 1-cm incision was made at the planned proximal anteromedial portal site and blunt dissection down to the capsule was performed without identification of the nerve. In group 3 (impossible) a 2- to 4-cm skin incision was made and the nerve was identified before placement of the portal.

Results: We found that 59 elbows in 56 patients had a subluxating ulnar nerve (31 elbows) or previous ulnar nerve transposition (28 elbows). The transposition had been subcutaneous in 21 and submuscular in 7. The proximal anteromedial portal was used in all but 3 cases (2 patients) of submuscular transposition that were early in the series. In those cases only 2 lateral portals were used for anterior compartment surgery. There were no operative ulnar nerve injuries related to the use of the proximal anteromedial portal.

Conclusions: Neither elbow arthroscopy nor specifically the use of the proximal anteromedial portal is contraindicated in patients with prior transposition or subluxation of the ulnar nerve. The management of the nerve can be based on the degree of certainty with which the nerve can be localized by palpation in the region of the planned portal.

Level Of Evidence: Level IV, therapeutic case series.