ARTHROSCOPIC ANATOMY OF THE LATERAL ELBOW - A COMPARISON OF 3 PORTALS

Ten fresh cadaveric elbows were used to evaluate the proximity of the radial nerve and its branches to three anterolateral portals. A proxim al anterolateral portal used routinely at our institution and located 2 cm proximal and 1 cm anterior to the lateral epicondyle was compared with the distal anterolateral portal described by Andrews and with a mid-anterolateral portal. The three portals were initially established without joint distention while the elbows were flexed 90 degrees. Mea surements were then obtained with and without joint distention at flex ion angles of 0 degrees and 90 degrees. The radial nerve was found to be an average distance of 3.8 mm at extension and 7.2 mm at 90 degrees of flexion from the distal anterolateral portal, located 3 cm distal and I cm anterior to the lateral epicondyle. Conversely, the distance between the proximal anterolateral portal cannula and the nerve was st atistically greater (p < 0.05), averaging 7.9 mm in extension and 13.7 mm in flexion. The remaining anterolateral portal, located I cm direc tly anterior to the lateral epicondyle, was found to be at a statistic ally greater average distance from the nerve than was the distal anter olateral portal but statistically closer than was the more proximal po rtal. The ability to visualize the joint arthroscopically was assessed using the three portals, and although the ulnohumeral joint could be adequately seen using ail portals, radiohumeral joint visualization wa s most complete and technically easiest using the most proximal portal . The proximal anterolateral portal, used in >100 elbow anthroscopies without evidence of radial nerve injury, is recommended for use as the standard lateral access site, allowing excellent visualization while maximizing the distance from the radial nerve throughout the elbow's r ange of motion.