Two Modified Anterolateral Portals in Elbow Arthroscopy: A Cadaveric Study

Abstract

To analyze the placement of two modified anterolateral portal sites in elbow arthroscopy and demonstrate the safety of each with respect to portal sites proximity to the radial nerve. Twelve fresh cadaveric elbow specimens (6 matched pairs) were prepared, anatomic landmarks were marked, and 4mm Steinman pins were inserted into three anterolateral portal sites in relation to the lateral epicondyle: 1) proximal, 2cm proximal and 2cm anterior 2) direct anterior, 2cm anterior 3) distal, 3cm distal and 1cm anterior. Each elbow was then dissected to reveal the course of the radial nerve. Digital photographs were taken of each specimen and the distance from the Steinman pin and the radial nerve was measured. Our proximal and direct anterior portal sites were found to be an average of 11.1mm and 13.8mm from the radial nerve, respectively. Similar to past studies we found the original distal anterolateral portal, as described by Andrews and Carson, in close proximity to the radial nerve, an average distance of 4.5mm. The distal anterolateral portal came in contact with the radial nerve 40% of the time, with 3 total Steinman pins piercing the nerve. There was a statistically significant difference in the distance between our proximal and distal anterior portals, as well as, our direct anterior and the distal portals to the radial nerve. No significant difference was found between the distance of the proximal and direct anterior portal sites. Our two modified, proximal and direct anterior, anterolateral portal sites should be considered safe and provides the surgeon with an adequate distance between the arthroscope and the radial nerve with little risk of iatrogenic injury. The distal portal puts the radial nerve at the most risk for iatrogenic injury. Our two modified anterolateral portal sites should be considered for use when performing elbow arthroscopy.