Determining the Elbow Flexion Angle That Minimizes Lateral Ulnar Collateral Ligament Deformity During Reconstruction.

BACKGROUND: Reconstruction of the lateral ulnar collateral ligament (LUCL) may be required to restore elbow stability. Minimizing changes in graft length through the arc of motion prevents deforming forces and loss of integrity. Currently, no consensus exists regarding the elbow flexion angle that minimizes LUCL deformation. The goal of this study was to determine the elbow flexion angle that would minimize graft length variability.

METHODS: Cadaveric specimens were prepared by reflecting the LUCL. A grid was made on the lateral epicondyle for various ligament origin points. Distances from each point in the grid to the supinator crest were recorded at 5 different angles with average lengths calculated. Variation around this length at each angle was measured.

RESULTS: Across the lateral epicondyle, the angle with the least variability from the average was 60°, significantly lower than other angles. Across all points, the minimal variability via a quadratic model was between 50° and 60°.

CONCLUSIONS: Graft length variability is influenced by the angle of elbow flexion during fixation. Our results indicate that this variability is minimized when the graft is fixated between 50° and 60° of flexion. Improving variability of an LUCL reconstruction may decrease graft stretching during elbow motion and maximize graft function while minimizing long-term complications.