The effect of age on elbow range of motion in pitchers

•Elbow ROM Pre-screening for adolescent pitchers is important for injury prevention.•Curveballs throwing may result in muscles tightness and limited forearm supination.•Repeated throwing may aggravate the valgus angle or cause the tissue/bony to adapt.•The stretch/massage to forearm should be provided to adolescent pitchers.

BackgroundAlteration of elbow range of motion (ROM) has been observed in baseball pitchers. This study aims to compare dominant elbow ROM between early-puberty, late-puberty, and young–adult pitchers.MethodsWe recruited 62 pitchers, consisting of 17 early-puberty (mean age 13.1 years old), 22 late-puberty (mean age 17.7 years old), and 23 young–adult players (mean age 19.4 years old). Dominant elbow ROMs was measured. One-way ANOVA was used to compare the differences in elbow ROM variables between 3 groups.ResultsLate-puberty pitchers exhibited a significantly lower elbow hyperextension and flexion than early-puberty or young–adult pitchers (P < .05). Valgus angle was significantly lower in young–adult (7.7°±5.5°) versus early-puberty (12.1°±2.3°) and late-puberty pitchers (13.0°±4.1°; P < .05). Young–adult pitchers had the largest forearm supination range (101.2°±18.1°), followed by early-puberty (82.5°±6.5°; P < .05) and late-puberty pitchers (70.6°±15.8°). Elbow flexion-hyperextension total range was smallest in late-puberty pitchers (130.3°±7.4°), followed by young–adult (142.6°±9.3°) and early-puberty pitchers (144.6°±8.3°; P < .05). Forearm pronation–supination total range was also smallest in late-puberty pitchers (142.0°±20.3°), followed by early-puberty (159.8°±9.5°) and young–adult pitchers (177.2°±20.8°; P < .05).ConclusionsThese results indicate that careful monitoring of the elbow and forearm range of motion should be undertaken in adolescent baseball pitchers to prevent and or minimize injury risk.