The Safety of Using Proximal Anteromedial Portals in Elbow Arthroscopy With Prior Ulnar Nerve Transposition

Purpose To report the safety of using the proximal anteromedial portal, using a simplified ulnar nerve management strategy derived from an earlier study, in a series of patients with previously transposed ulnar nerves. Methods A retrospective review of all elbow arthroscopies performed by a single surgeon from 2009 to 2014 was performed. The following techniques were used if, by palpation, localization of the ulnar nerve was considered to be certain (group 1) or uncertain (group 2): In group 1 (certain) the proximal anteromedial portal was established in the normal antegrade fashion. In group 2 (uncertain) a 1- to 3-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. The nerve was not visualized but sometimes was palpated through the wound to confirm its location anteriorly or posteriorly. If there was a disparity between the prior operative records and the physical examination findings, the nerve was explored through a 3- to 4-cm incision. Results We reviewed 394 elbow arthroscopy cases, 22 of which had a prior transposed ulnar nerve (21 subcutaneous and 1 submuscular) that required anterior-compartment arthroscopic surgery. Group 1 (certain location) consisted of 9 elbows (41%), whereas group 2 (uncertain location) consisted of 13 (59%). In 2 cases in group 2, the ulnar nerve was explored because of the disparity between the previous medical records and the physical examination findings. There were no operative ulnar nerve injuries related to the use of the proximal anteromedial portal. Conclusions The proximal anteromedial portal was able to be used safely in patients with prior transposition of the ulnar nerve. This was achieved by using an algorithm based on the degree of certainty with which the nerve can be localized in the region of the planned portal by clinical palpation. Level of Evidence Level IV, therapeutic case series.