Background: The rates of ulnar collateral ligament injury and surgery continue to rise in baseball. Increased ball velocity and elbow varus torque may correlate with the increased risk of injury. Hypothesis: Increased ball weight and/or size correlate with decreased elbow varus torque during pitching.

Injury of the ulnar collateral ligament (UCL) is common in baseball players. Pitchers are most commonly affected and most likely to have surgery for this injury. The gold standard surgical treatment is UCL reconstruction with autograft; yet, UCL repair with collagen-coated suture tape (ie, internal brace) has shown to be equally effective, and both procedures demonstrate high rates of return to sport and similar postoperative elbow function. However, revision UCL reconstructions have less favorable outcomes regardless of technique.

Background: The ulnar collateral ligament (UCL) of the elbow is commonly injured in baseball athletes. When assessed in the supine abducted and externally rotated (ABER) position using stress ultrasonography (sUS), even before applying a valgus load, gravity pulls on the forearm, creating an initial valgus load that may distort the resting joint space measurement. Purpose/Hypothesis: The purpose of this study was to measure the valgus stress effect of gravity on the resting joint space and determine if a varus-stressed joint space provides a better baseline measurement. It was hypothesized that there would be a greater resting joint space in the throwing arm in the ABER position as a result of UCL laxity but no difference in joint space under varus stress compared to the nonthrowing arm.