Effect of olecranon resection on joint stability and strain of the medial ulnar collateral ligament.

This study aimed to assess the effect of posteromedial olecranon resection on the stability of the elbow joint, forearm kinematics, and strain in the anterior bundle of the medial ulnar collateral ligament. Seven elbows were tested after resecting all soft tissues except the capsuloligamentous structures. Varus-valgus angulation, forearm rotation, and the length of the anterior bundle of the medial ulnar collateral ligament were measured at 3 posteromedial olecranon resection stages of 0, 4, and 8 mm, and at elbow flexion angles of 30 degrees, 60 degrees, and 90 degrees. Posteromedial olecranon resection significantly increased varus and valgus laxities at 60 degrees and 90 degrees of elbow flexion but had a larger effect on varus motion than valgus movement. With more posteromedial olecranon resection, the valgus angulation and varus-valgus laxity proportionally increased. In most cases, parallel resections of the posteromedial olecranon significantly decreased the functional varus-valgus stiffness. There was no significant effect on strain in the anterior bundle of the medial ulnar collateral ligament due to olecranon resection. When treating an overhead athlete with posteromedial olecranon impingement, the resection should be limited to osteophytic overgrowth. Throwers may be susceptible to ulnar collateral ligament injury following posteromedial olecranon resection due to increased elbow laxity.