Arthroscopic Assessment of the Medial Collateral Ligament Complex of the Elbow

The extent that the medial collateral ligament complex could be visualized by arthroscopy was determined in 10 fresh cadaveric elbows from 10 individuals. We care fully exposed the medial collateral ligament complex through a muscle-splitting incision before performing ar throscopy. The anterior and posterior bundles were identified and marked by placing 4.0 nylon sutures deep to the bundles to aid in arthroscopic visualization. A por tion of the anterior bundle was visible in only one elbow and in that elbow only the most anterior 25% of the anterior bundle was seen. Attempts to visualize the an terior bundle through additional portals were unsuc cessful. Varying the flexion angle of the cadaveric elbow from 0° to 130° also failed to improve visualization. Con versely, the entire posterior bundle, including humeral and ulnar insertion sites, could be seen in all 10 speci mens using the posterior portals. We also noted that direct pressure was placed on the ulnar nerve in all specimens when the arthroscope or any arthroscopic instrument was advanced into the posteromedial gutter in contact with the posterior bundle because of its prox imity immediately adjacent to the ulnar nerve. The in ability to reliably see the anterior bundle and the hu meral or ulnar insertion sites of this ligament may limit the value of the arthroscope when assessing medial collateral ligament injuries. Additionally, great care should be taken when using the arthroscope or other instruments in the posteromedial gutter because the ul nar nerve lies immediately adjacent to the thin posterior bundle and capsule.