Background:

Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, with variable reported effects on velocity and traditional rate statistics. Currently, no studies have evaluated spin rate in the context of return to play (RTP) after injury. Greater spin rate has become increasingly sought after in the baseball community, as it is believed to be a vital aspect of pitch effectiveness.

Purpose/Hypothesis:

The purpose was to evaluate the effect of primary UCLR on fastballs (FB) and sliders (SL) of MLB pitchers in terms of spin rate, velocity, hard-hit rate, and whiff rate. It hypothesized that the post-UCLR FB and SL spin rates, velocity, and whiff rate would be significantly decreased versus their pre-UCLR levels, while the FB and SL hard-hit rates would be higher in comparison with pre-UCLR levels.

Study Design:

Case series; Level of evidence, 4.

Methods:

In total, 42 pitchers who underwent UCLR and returned to MLB play were identified from public records from 2016 to 2019. The Statcast system was used to collect spin rate, velocity, hard-hit rate, and whiff rate for 4-seam FB (4FB), 2-seam FB (2FB), and SL for pitchers in the preinjury year as well as the 2 years after return from UCLR. Data were analyzed using the appropriate statistical tests.

Results:

A total of 36 pitchers met the inclusion criteria, and 31 of the eligible 36 players (86.1%) were able to return to MLB pitching (RTP). There were no significant decreases for 4FB, 2FB, or SL in spin rate, measured in revolutions per minute (rpm), when comparing preinjury levels with the first and second seasons after return. There was a significant decrease in velocity for the 2FB in the first season (92.9 vs 93.7 miles per hour [mph]; P = .045) but not the second season (93 mph; P = .629) after RTP in comparison with pre-UCLR levels. For the 2FB, there was a significant increase in spin rate between preinjury and RTP season 2 (2173.5 vs 2253 rpm; P = .022). For the SL, there was a significant increase in spin rate between preinjury and RTP season 2 (2245.1 vs 2406 rpm; P = .016).

Conclusion:

A cohort of MLB pitchers who underwent UCLR and returned to the MLB level demonstrated no significant decreases in the spin rate, velocity, whiff rate, or hard-hit rate of 4FB, 2FB, or SL at 2 years after UCLR.

中文翻译：

---

尺侧副韧带重建不会降低大联盟投手的旋转速度或表现

背景：

尺侧副韧带重建 (UCLR) 通常在美国职业棒球大联盟 (MLB) 投手中进行，对速度和传统速率统计的报告影响不同。目前，没有研究在伤后恢复比赛（RTP）的背景下评估旋转速度。更高的旋转速度在棒球界越来越受到追捧，因为它被认为是投球效率的一个重要方面。

目的/假设：

目的是评估初级 UCLR 对 MLB 投手的快球 (FB) 和滑块 (SL) 的旋转速率、速度、重击率和嗅觉速率的影响。它假设 UCLR 后的 FB 和 SL 旋转速率、速度和嗅觉速率将比 UCLR 前的水平显着降低，而与 UCLR 前的水平相比，FB 和 SL 的重击率会更高。

学习规划：

案例系列；证据水平，4。

方法：

从 2016 年到 2019 年的公共记录中，总共确定了 42 名接受 UCLR 并重返 MLB 比赛的投手。Statcast 系统用于收集 4 缝 FB（4FB )、2-seam FB (2FB) 和 SL 用于投手在受伤前一年以及从 UCLR 归来后的 2 年。使用适当的统计检验分析数据。

结果：

共有 36 名投手符合入选标准，符合条件的 36 名球员中有 31 名（86.1%）能够重返 MLB 投手（RTP）。在将伤前水平与回归后的第一和第二赛季进行比较时，4FB、2FB 或 SL 的旋转速率没有显着下降，以每分钟转数 (rpm) 衡量。与前一季相比，RTP 后第一季的 2FB 速度显着下降（92.9 对 93.7 英里/小时 [mph]；P = .045），但在第二季（93 mph；P = .629）则没有-UCLR 水平。对于 2FB，在伤前和 RTP 第 2 季之间旋转速度显着增加（2173.5 对 2253 rpm；P= .022)。对于 SL，在伤前和 RTP 第 2 季之间旋转速率显着增加（2245.1 对 2406 rpm；P = .016）。

结论：

一组接受 UCLR 并恢复到 MLB 水平的 MLB 投手在 UCLR 后 2 年显示旋转速率、速度、嗅觉速率或 4FB、2FB 或 SL 的重击率没有显着降低。