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Published on: March 12, 2021
Major League Baseball Pitchers' Arm Angles Measured on Game Videos Were Not Associated With an Increased Risk of
Daniel Lipa1, Krishin Shivdasani1,2, Michael Scheidt1
1Department of Orthopaedic Surgery & Rehabilitation, Loyola University Health System, Maywood, Illinois, U.S.A.
Purpose:
To use a publicly available Major League Baseball (MLB) game video to investigate whether pitch type and pitching elbow angle at peak valgus stress and at release point are associated with the odds of undergoing Tommy John surgery.
Methods:
This case-control study compared pitchers who had undergone ulnar collateral ligament reconstruction to a matched control group of pitchers who had not undergone the surgery. Pitchers were selected based on inclusion in online baseball player and injury databases, including the MLB Health and Injury Tracking System, with those pitching fewer than 10 innings in MLB excluded. The experimental group included measurements from all pitchers before their ulnar collateral ligament injury who eventually had undergone Tommy John surgery since 2010. Greedy matching algorithm was used to select a matched cohort of pitchers based on age, height, weight, years in the MLB, hand dominance, pitching role (starter vs reliever), and average pitching velocity. Conditional logistic regression models were used to measure the association between pitch angle and log odds of receiving a Tommy John surgery.
Results:
There were 249 paired cases and controls (N = 498) included in the conditional logistic regression analysis. There was no statistically significant association between average elbow angle at peak valgus stress and the odds of undergoing Tommy John surgery (odds ratio, 1.02; 95% confidence interval, 0.99-1.03; P = .14).
Conclusions:
Peak valgus elbow angle, release point angles, and combinations of angles and specific pitches were not associated with an increased risk of undergoing Tommy John surgery.
Level Of Evidence:
Level III, observational study, case-control design.
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