Athletic Hip Injuries in Major League Baseball Pitchers Associated with UCL Pathology

Abstract

Objectives: Ulnar collateral ligament (UCL) reconstruction is a reliable treatment for elite overhand throwers with UCL pathology. In recent years, this operation has become increasingly common among Major League Baseball (MLB) pitchers. Predisposing factors and associated comorbidities, however, have not been well elucidated in the literature. The purpose of this investigation is to determine if professional baseball pitchers who underwent UCL reconstruction had an increased incidence of hip or groin injuries 4 years prior to or following their surgery. We hypothesized that MLB pitchers who sustained hip or groin injuries may have been more likely to develop UCL pathology due to kinetic chain alterations and overcompensation at the distal upper extremity during overhand throwing. Methods: This case controlled study utilized a comprehensive list of all 247 MLB players who underwent UCL reconstruction between 2005 and 2017, through aggregation of online publicly accessible data. Application of inclusion criteria yielded a final sample size of 145. These athletes’ injury histories were identified using systematic online searches and cross referenced with the official MLB disabled list. Age, playing time, and ERA-matched controls were generated for 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, 18%, was identified in matched controls during a similar timeframe (p = 0.049). This represents an odds ratio of 1.74, indicating that players who underwent a UCL reconstruction were 74% more likely to have sustained a hip, groin or hamstring injury within an eight-year timeframe compared to matched controls. Hip injuries, specifically, were independently associated with UCL reconstruction compared to matched controls (p = 0.027). Conclusion: The results of this study demonstrate that MLB pitchers who required UCL reconstruction sustained a higher frequency of hip injuries both before and after surgery compared to matched controls. This association is significant as treatment of antecedent hip pathology, as well as emphasis on hip and core muscle mobility and strengthening, may help reduce the UCL injury burden in MLB pitchers.