Erickson Brandon J, Chalmers Peter N, Axe Michael J, Romeo Anthony A
Midwest Orthopaedics at Rush, Rush University Medical Center, Chicago, Illinois, USA.
Department of Orthopaedic Surgery, Shoulder and Elbow Division, University of Utah, Salt Lake City, Utah, USA.
Orthop J Sports Med. 2017 Mar 24;5(3):2325967117695085. doi: 10.1177/2325967117695085. eCollection 2017 Mar.
Empirical evidence has suggested a connection between youth pitch counts and subsequent elbow injury. For players within the Little League World Series (LLWS), detailed historical player data are available. Some of these players progress to both professional play and require an ulnar collateral ligament reconstruction (UCLR).
To determine the percentage of LLWS pitchers who proceed to play professional (major or minor league) baseball, the rate of UCLR in former LLWS pitchers who played professional baseball, and the risk to those who exceeded current pitch count recommendations while playing in the LLWS.
Cohort study; Level of evidence, 3.
All LLWS pitchers from 2001 through 2009 from all teams and countries were identified, and all performance data were extracted. A professional (major and minor league) baseball database was then searched to determine whether each former LLWS pitcher played professional baseball. These professional players were then searched for using publicly available databases to determine whether they underwent UCLR.
Overall, 638 adolescents pitched in the LLWS between 2001 and 2009; 62 (10%) progressed to professional play. Of the 56 minor league players, 25 (45%) pitched. Of the 6 Major League Baseball players, 3 (50%) pitched. Three former LLWS pitchers (5%) who played professionally underwent UCLR. In former LLWS pitchers who exceeded pitch counts and played professionally, 50% (2/4) required UCLR, while only 1.7% (1/58) of those who did not exceed pitch count recommendations required UCLR ( = .009). Similarly, among former LLWS pitchers who subsequently played professionally, 23.1% of those who played as a pitcher required UCLR while 0% of those who also played other positions required UCLR ( = .008).
Progression from LLWS pitching to professional baseball is uncommon. Among youth players, both diversification (playing other positions besides pitcher) as well as following current pitch limit regulations may protect against UCLR.
经验证据表明青少年投球次数与随后的肘部损伤之间存在联系。对于参加小联盟世界系列赛（LLWS）的球员，可以获取详细的球员历史数据。其中一些球员后来进入职业比赛并需要进行尺侧副韧带重建（UCLR）。
确定进入职业（大联盟或小联盟）棒球比赛的LLWS投手的百分比、曾参加职业棒球比赛的前LLWS投手中UCLR的发生率，以及在LLWS比赛中超过当前投球次数建议的球员面临的风险。
队列研究；证据等级，3级。
确定2001年至2009年所有球队和国家的所有LLWS投手，并提取所有表现数据。然后搜索职业（大联盟和小联盟）棒球数据库，以确定每位前LLWS投手是否参加过职业棒球比赛。接着使用公开可用数据库搜索这些职业球员，以确定他们是否接受了UCLR。
总体而言，2001年至2009年间有638名青少年在LLWS中担任投手；62人（10%）进入职业比赛。在56名小联盟球员中，25人（45%）担任投手。在6名美国职业棒球大联盟球员中，3人（50%）担任投手。3名曾参加职业比赛的前LLWS投手（5%）接受了UCLR。在超过投球次数并参加职业比赛的前LLWS投手中，50%（2/）需要进行UCLR，而未超过投球次数建议的球员中只有1.7%（1/58）需要进行UCLR（P = 0.009）。同样，在随后参加职业比赛的前LLWS投手中，担任投手的球员中有23.1%需要进行UCLR而担任其他位置的球员中这一比例为0%（P = 0.008）。
从LLWS投球发展到职业棒球并不常见。在青少年球员中，多样化（除投手外还担任其他位置）以及遵守当前的投球次数限制规定可能预防UCLR。
