Changes in performance following oblique strains in Major league Baseball players.

Abstract

The recurrent and forceful rotational demands placed on the trunk during pitching and batting generate significant stress on the oblique muscles, predisposing them to strain. The objective of this study was to examine performance outcomes in Major League Baseball (MLB) pitchers and hitters who suffered an oblique strain. A retrospective analysis was conducted using MLB pitchers and hitters who suffered an oblique strain between 2016 and 2023. Players who had data available in Baseball Savant and Baseball Reference for the years before and after an oblique strain were included, with pitching and hitting metrics collected from both databases. Those who were injured in the year they entered the MLB were excluded. Statistical analyses were performed using player performance data from MLB seasons spanning 2015 to 2024. Paired two-sample T-tests and linear regression models were used to assess statistical differences and identify changes in performance outcomes. A total of 85 MLB hitters and 72 MLB pitchers met the inclusion criteria. For hitters, slugging percentage (SLG) decreased from 0.43 to 0.38 (95% CI 0.026-0.061; <i>p</i> < 0.001), on-base percentage (OBP) decreased from 0.323 to 0.303 (95% CI 0.009-0.030; <i>p</i> < 0.001), on-base plus slugging (OPS) decreased from 0.749 to 0.686 (95% CI 0.037-0.089; <i>p</i> < 0.001), OPS adjusted for league and park factors (OPS+) decreased from 103.2 to 92.0 (95% CI 4.1-18.3; <i>p</i> = 0.002), batting average on balls in play (BABIP) decreased from 0.307 to 0.280 (95% CI 0.012-0.042; <i>p</i> < 0.001), average exit velocity decreased from 83.3 to 82.3 mph (95% CI 0.63-1.49; <i>p</i> < .001), hard-hit rate declined from 25.3% to 23.0% (95% CI 1.41-3.30; <i>p</i> < .001), and hyperspeed decreased from 91.9 to 91.5 mph (95% CI 0.23-0.52; <i>p</i> < .001). Among pitchers, strikeouts per nine innings (SO/9) decreased from 9.13 to 8.44 (95% CI 0.07-1.30; <i>p</i> = 0.030). Time to return to MLB was not associated with changes in post-injury performance in either group. Oblique strain injuries in MLB players were associated with declines in hitting performance but had little association with pitching metrics. These findings suggest that physicians and therapists can tailor counseling and rehabilitation expectations based on player position, with hitters potentially requiring more targeted recovery strategies to restore rotational power.