研究背景與目的：肩關節活動度的改變常見於棒球選手身上，而臨床上亦常見棒球選手手肘關節
產生攣縮的情形，但是少有相關的研究證據被發表。因此，本研究之目的：⑴比較青棒選手與一
般人手肘關節活動角度之差異；⑵比較青棒選手慣用側及非慣用側手肘關節活動度的差異；⑶比
較投手與野手手肘關節活動度之差別。方法：本研究徵召22名青棒選手和22名大學生，以關節
量尺進行手肘關節活動度之量測，測量慣用手及非慣用手手肘的伸直、彎曲、旋前、旋後以及外
翻之角度，並利用伸直、彎曲、旋前、旋後角度計算出彎曲—伸直總角度和旋前—旋後總角度。
結果與討論：結果顯示青棒選手在慣用手手肘彎曲、過度伸展、旋後、旋後-旋前總角度及非慣
用手旋後角度上均顯著小於一般年輕人（p<.05）；其餘角度與一般年輕人無明顯差異。青棒選手在慣用手與非慣用手手肘關節角度比較上，慣用手之手肘彎曲、旋後、及彎曲—伸直總角度均小於非慣用手，慣用手之手肘外翻角度大於非慣用手。而投手在手肘外翻角度上又大於野手；其他角度，無論是慣用手或非慣用手，投手與野手均無顯著差別。結論：青棒選手在手肘關節活動度與一般人有明顯的差異可能是由於長期的棒球訓練所造成，其中，需特別注意投手在手肘外翻角度的變化。

Background: Altered shoulder range of motion was more seen in baseball players. However,very few regarding the youth players and their elbow range of motion (ROM) differences in handedness and defended position could be found. Therefore, the purposes of this study were to compare the differences of the elbow ROM between dominated and non-dominated sides and
to determine if there was any difference existed between different defended positions of high school baseball players. Methods: Twenty-two high school baseball players and 22 college students participated in the study. ROM including flexion, hyper-extension, pronation, supination,
and valgus of the dominant and non-dominant elbows were measured by a goniometer.Results: Baseball players showed significantly smaller ROM of their dominant elbow flexion,hyperextension, supination, pronation to supination total range, and non-dominant supination than subjects in the comparison group. Baseball players also demonstrated smaller ranges of
their dominant elbow flexion, supination, and flexion-extension total range than range of their non-dominant side. The valgus carry angle of pitchers’ dominant elbow was larger than the nondominant arm elbow.
Conclusions: Long term baseball training may result in osseous or soft
tissue adaptive changes of the dominant elbow. Sequentially, it would alter the joint mobility of baseball players’ dominant elbow, especially for pitchers.