Athletic Hip Injuries in Major League Baseball Pitchers Associated With Ulnar Collateral Ligament Tears

Background: Ulnar collateral ligament (UCL) reconstruction is a reliable treatment for elite overhand throwers with UCL tears. In recent years, this procedure has become increasingly common among Major League Baseball (MLB) pitchers. Predisposing factors and associated comorbidities, however, have not been fully elucidated. Purpose/Hypothesis: The purpose of this study was to determine whether professional baseball pitchers who underwent UCL reconstruction had an increased incidence of hip or groin injuries 4 years before or after surgery. We hypothesized that MLB pitchers who sustain hip or groin injuries may be more likely to develop UCL tears because of alterations and overcompensation in the kinetic chain during overhand throwing. Study Design: Cohort study; Level of evidence, 3. Methods: A comprehensive list of all 247 MLB players who underwent UCL reconstruction between 2005 and 2017 was created using publicly accessible online data. The application of inclusion criteria yielded a final sample size of 145 athletes. These athletes’ injury histories were identified and cross-referenced with the official MLB disabled list. Matched controls were generated for a comparison of results. Results: Of the 145 MLB pitchers who underwent UCL reconstruction between 2005 and 2017, 40 (27.6%) endured a proximal lower extremity injury within 4 years of their surgery. Specifically, 16 pitchers sustained hip injuries, 13 suffered hamstring injuries, and 14 experienced groin injuries. A significantly lower rate of hip- and groin-related injuries (17.9%) was identified in matched controls during a similar time frame (P = .049). Conclusion: The results of this study demonstrate that MLB pitchers who required UCL reconstruction sustained a higher frequency of proximal lower extremity injuries both before and after surgery compared with matched controls. This finding is significant as the treatment of antecedent hip lesions, as well as an emphasis on hip and core muscle mobility and strengthening, may help reduce injuries to the UCL.