Posterior Interosseous Nerve Proximity to Cortical Button Implant for Distal Biceps Repair With Single and 2-Incision Approaches

Abstract

Fixation with a cortical button is the biomechanically strongest surgical approach for distal biceps repair, and utilization of the 2-incision approach may provide a more anatomical repair and improved terminal supination strength. The risk of injury to the posterior interosseous nerve (PIN) associated with this approach requires further investigation. A distal biceps repair with a cortical button was performed on 10 cadavers, 5 utilizing the single-incision approach and 5 utilizing the 2-incision approach. Contrast was injected into the radial nerve and computed tomography scans were obtained. The distance between the drilled cortical perforation and the PIN was measured. The mean distance from the cortical perforation to the PIN was not significantly different between approaches (9.4 mm and 8.8 mm). A PIN entrapment was seen in 0 out of 5 for the single-incision approach and 1 out of 5 for the 2-incision approach. Distal biceps repair with cortical button fixation places the PIN at risk of injury regardless of the approach used. Methods of fixation that require bicortical drilling should be especially avoided when using the 2-incision approach. Distal biceps repair utilizing bicortical drilling for fixation through a 2-incision approach poses high risk of injury to the PIN and should be avoided.