Tanenbaum Joseph E, Knapik Derrick M, Karns Michael R, Salata Michael J, Gillespie Robert J, Voos James E
Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio, USA.
Orthop J Sports Med. 2022 Apr 26;10(4):23259671221090899. doi: 10.1177/23259671221090899. eCollection 2022 Apr.
Major League Baseball (MLB) adopted a rule change in 2016 to reduce the number of collisions that occur when a player slides into a base. The effect of rule 6.01(j) has not been quantified, and it remains unknown if this rule change has led to improved player safety.
Rule 6.01(j) would be associated with a reduction in the number of collision-related injuries at second base.
Cohort study; Level of evidence, 3.
Using data from the MLB Health and Injury Tracking System, we quantified the number of collision-related injuries for defensive (ie, fielding) players in the infield at the major and minor league levels between the 2010 and 2019 seasons. We compared the median number of collision-related injuries for defensive players in the infield from before (2010-2015) to after (2016-2019) the implementation of rule 6.01(j) and also calculated the difference in location of the median from the seasons before versus after the rule change. An additional 3 analyses were performed to support or contradict a conclusion that any observed reduction in injuries at the start of the 2016 season was likely caused by the adoption of rule 6.01(j).
The median number of collision-related injuries for defensive players at second base decreased from 58.5 to 37.5 injuries per season after the rule change, which was a 36% decrease (difference in location, 19.5 [95% CI, 5.0 to 31.0]; = .019). In contrast, the median number of collision-related injuries at first base decreased by only 14.1%, from 49.5 before to 42.5 after the rule change (difference in location, -9.0 [95% CI, -4.0 to 18.0]; = .16), and the median number of collision-related injuries per season at third base was unchanged at 15 per season.
This rule change was associated with a decrease in the number of collision-related injuries, with the largest effect observed at second base, as expected.
美国职业棒球大联盟（MLB）在2016年通过了一项规则变更，以减少球员滑垒时发生碰撞的次数。规则6.01(j)的效果尚未量化，该规则变更是否提高了球员安全性仍不清楚。
规则6.01(j)将与二垒碰撞相关损伤的数量减少相关。
队列研究；证据等级，3级。
利用MLB健康与损伤追踪系统的数据，我们对2010年至2019赛季美国职业棒球大联盟及小联盟内场防守（即守备）球员的碰撞相关损伤数量进行了量化。我们比较了规则6.01(j)实施前（2010 - 2015年）和实施后（2016 - 2019年）内场防守球员碰撞相关损伤的中位数，并计算了规则变更前后赛季中位数位置的差异。还进行了另外三项分析，以支持或反驳2016赛季初观察到的任何损伤减少可能是由于采用规则6.01(j)导致的这一结论。
规则变更后，二垒防守球员碰撞相关损伤的中位数从每个赛季58.5例降至37.5例，降幅为36%（位置差异，19.5 [95%可信区间，5.0至31.0]；P = 0.019）。相比之下，一垒碰撞相关损伤的中位数仅下降了14.1%，从之前的49.5例降至规则变更后的42.5例（位置差异， - 9.0 [95%可信区间， - 4.0至18.0]；P = 0.16），三垒每个赛季碰撞相关损伤的中位数保持不变，为15例。
如预期的那样，这一规则变更与碰撞相关损伤数量的减少相关，在二垒观察到的效果最为显著。
