Cohen Samuel A, Portney Daniel A, Cohen Landon E, Bolia-Kavouklis Ioanna, Weber Alexander E, Saltzman Matthew D
Stanford University School of Medicine, Stanford University, Stanford, California, USA.
Pritzker School of Medicine, University of Chicago, Chicago, Illinois, USA.
Orthop J Sports Med. 2022 Mar 7;10(3):23259671211065756. doi: 10.1177/23259671211065756. eCollection 2022 Mar.
Approximately 25% of Major League Baseball (MLB) pitchers undergo medial ulnar collateral ligament reconstruction (UCLR) during their careers.
To identify risk factors for UCLR that are specific to 2 subgroups of MLB pitchers: right (RHPs)- versus left-handed pitchers (LHPs) and starting (SPs) versus relief pitchers (RPs).
Case-control study; Level of evidence, 3.
We included 109 MLB pitchers who had undergone UCLR between 2007 and 2019 and had sufficient preinjury data in the 3 years before surgery (T3, T2, T1). A 2:1 matched control cohort was selected for comparison. Pitch velocity, release location, and ball movement were compared between the UCLR and control cohorts in both subgroups in the years before surgery (RHPs vs LHPs and SPs vs RPs). Binary logistic regression was used to identify independent risk factors for UCLR.
The mean horizontal release location for the UCLR group was 5.8 cm more lateral than for the control group ( = .028). For all pitchers, every 2.5-cm lateral shift in release location in the years leading up to UCLR equated to a 3.7% increase in the odds of UCLR. For RPs, this risk was more substantial: a 5.8% increase in odds per 2.5 cm. SPs in the UCLR group demonstrated significantly different T1 horizontal release locations compared with SPs in the control group, though not to a statistically significant change over the 3 years before surgery. However, in the 3 years before surgery, the horizontal release location for RPs in the UCLR group moved 2.1 cm more lateral, as compared with 2.7 cm more medial for RPs in the control group ( = .007). For LHPs, a decrease in mean pitch velocity by 1 mph (1.6 km/h) in the years leading up to surgery increased the odds of UCLR by 45%.
Increasing lateralization of release point in the years before surgery increased the risk of UCLR, specifically for relievers. Our findings add to the growing body of evidence that release location is an important variable in analyzing the risk of UCLR in MLB and that risk stratification may be dependent on pitcher characteristics such as position, handedness, and weight.
在美国职业棒球大联盟（MLB）中，约25%的投手在其职业生涯中会接受内侧尺侧副韧带重建术（UCLR）。
确定MLB投手中两个亚组特有的UCLR风险因素：右投手（RHPs）与左投手（LHPs），以及先发投手（SPs）与救援投手（RPs）。
病例对照研究；证据等级为3级。
我们纳入了109名在2007年至2019年间接受UCLR且在手术前3年（T3、T2、T1）有足够伤前数据的MLB投手。选择一个2:1匹配的对照队列进行比较。在手术前几年，比较了UCLR组和对照组在两个亚组中的投球速度、投球位置和球的运动轨迹（右投手与左投手、先发投手与救援投手）。采用二元逻辑回归来确定UCLR的独立风险因素。
UCLR组的平均水平投球位置比对照组外侧多5.8厘米（P = 0.028）。对于所有投手，在UCLR前几年投球位置每向外偏移2.5厘米，UCLR的几率就增加3.7%。对于救援投手，这种风险更为显著：每2.5厘米几率增加5.8%。UCLR组的先发投手与对照组的先发投手相比，T1水平投球位置有显著差异，尽管在手术前3年没有统计学上的显著变化。然而，在手术前3年，UCLR组救援投手的水平投球位置向外移动了2.1厘米，而对照组救援投手向内移动了2.7厘米（P = 0.007）。对于左投手，在手术前几年平均投球速度每降低1英里/小时（1.6公里/小时），UCLR的几率增加45%。
手术前几年投球点的外侧化增加会增加UCLR的风险，特别是对于救援投手。我们的研究结果进一步证明，投球位置是分析MLB中UCLR风险的一个重要变量，并且风险分层可能取决于投手的特征，如位置、投球手习惯和体重。
