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. 2025 May 21;7(4):101171.
doi: 10.1016/j.asmr.2025.101171. eCollection 2025 Aug.

Major League Baseball Pitchers Experienced Increased Flexor Tendon and Forearm Injuries 2 Years After Pitch Clock Implementation

Troy B Puga  1 , McKenna W Box  1 , Winston Scambler  2 , Hans Drawbert  1 , John T Riehl  1
Affiliations

Major League Baseball Pitchers Experienced Increased Flexor Tendon and Forearm Injuries 2 Years After Pitch Clock Implementation

Troy B Puga et al. Arthrosc Sports Med Rehabil. .

Abstract

Purpose: To evaluate the incidence of pitcher injuries 2 years after implementation of the Major League Baseball (MLB) pitch clock.

Methods: Injury data were collected for the 2021, 2022, 2023, and 2024 MLB seasons using the fangraphs.com injury database. The incidence rate ratio was calculated to compare the injury rate for the 2024 season with that for each of the 2021, 2022, and 2023 seasons. Data were pooled for the pre- and post-pitch clock seasons and were compared in similar fashion to the individual seasons using the incidence rate ratio. The z test for proportions was used to determine significance.

Results: The 2024 MLB season, with 366 overall injuries, showed a decrease in the overall number of injuries compared with the 2021 season, which had 467 overall injuries (P < .001), and the 2022 season, which had 461 overall injuries (P < .001). The 2024 season, with 61 lower-extremity injuries, showed a decrease in the number of lower-extremity injuries compared with the 2021 season, which had 104 lower-extremity injuries (P = .001), and the 2022 season, which had 87 lower-extremity injuries (P = .03). The 2024 season, with 55 torso injuries, showed a decrease in the number of torso injuries compared with the 2022 season, which had 75 torso injuries (P = .04). The 2024 season, which had 62 flexor tendon/forearm injuries, revealed a statistically significant rise in flexor tendon/forearm injuries compared with the 2021 season, with 37 injuries (P = .01); the 2022 season, with 33 injuries (P = .005); and the 2023 season, with 36 injuries (P = .02). There was no statistically significant difference in the number of ulnar collateral ligament operations when the 2024 MLB season (n = 34) was compared with the 2021 season (n = 20), 2022 season (n = 30), and 2023 season (n = 27). When the pre-and post-pitch clock pooled data were compared, there was a significant decrease in overall injuries (P < .001) and lower-extremity injuries (P = .004). This comparison also revealed a significant increase in flexor tendon/forearm injuries (P = .04).

Conclusions: Two years after the implementation of the MLB pitch clock, there was a decrease in the incidence of overall injury rates and lower-extremity injuries. There remained no associated increase in ulnar collateral ligament operations 2 years after implementation. However, the pre- versus post-pitch clock comparison showed a rise in flexor tendon and forearm injuries in the 2024 season.

Level of evidence: Level III, retrospective cohort study.

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Conflict of interest statement

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: J.T.R. reports a consulting or advisory relationship with Arthrex and has a patent with royalties paid to Arthrex. All other authors (T.B.P., M.W.B., W.S., H.D.) declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

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