We evaluated performance and salary outcomes following ulnar collateral ligament (UCL)
surgery in Major League Baseball (MLB) pitchers. This retrospective cohort included
277 pitchers who underwent surgery between 2000 and 2024. Among the 267 with available
return-to-play (RTP) data, 85% returned to professional competition, and 35% had a
multiyear contract at the time of injury. Performance, measured as league-adjusted
changes in earned run average (ERA), fielding independent pitching (FIP), and walks
plus hits per inning pitched (WHIP), declined significantly after return (ERA +1.45,
95% CI 0.63–2.26, p=0.01; FIP +0.88, 0.50–1.27, p<0.01; WHIP +0.26, 0.14–0.37, p<0.01).
In contrast, salary increased by an average of 16.6% after era adjustment. In multivariable
models, greater MLB experience before injury (p=0.03), higher pre-injury wins above
replacement (p<0.01), and multiyear-contract status (p<0.01) independently predicted
higher post-injury salary, while age, handedness, and in-season injury were not significant.
Having a multiyear contract was also the only significant predictor of RTP (p=0.049).
Overall, MLB pitchers demonstrated significant performance declines despite salary
growth, reflecting service-time progression and contractual security rather than immediate
post-injury output.
