Identifying the Safe Zone in Arthroscopic Anterior Elbow Capsulectomy: A Cadaveric Study

The authors assessed the effects of forearm rotation on the proximity of the radial nerve and medial collateral ligament (MCL) to a proximal and a more distal arthroscopic anterior elbow capsulectomy. Arthroscopy was performed on 10 cadaveric specimens. Sutures were passed lateral to medial at the level of the radiocapitellar joint and at the proximal edge of the annular ligament. Dissection measured the distance to the radial nerve from the lateral starting point and to the MCL from the medial exit point in varying degrees of forearm rotation. The extent of brachialis muscle coverage of the radial nerve was documented. The distance from the starting point to the radial nerve increased in pronation at both levels. The medial extent of the capsulectomy remained a safe distance from the MCL. Brachialis muscle covered the radial nerve at both levels. Pronation increases the capsulectomy safe zone, including more distally, before encountering the radial nerve; the MCL is not at risk. [Orthopedics. 2020;43(5):e399-e403.].