Gilmer Gabrielle G, Washington Jessica K, Dugas Jeffrey R, Andrews James R, Oliver Gretchen D
J Sport Rehabil. 2019 Feb 1;28(2):196-204. doi: 10.1123/jsr.2017-0276. Epub 2018 Nov 30.
Studies have found that a 20% reduction in energy generation from the lumbopelvic-hip complex during overhead throws leads to a 34% increase in load on the shoulder.
The purpose of this study was to assess the effects of lumbopelvic-hip complex stability, via the single leg squat assessment, on throwing mechanics of softball athletes.
Prospective cohort study.
Laboratory setting.
A total of 50 softball athletes (164.0 [104.0] cm, 65.6 [11.3] kg, 16.3 [3.8] y, 8.61 [3.62] y of experience) performed 3 overhead throws and a single leg squat on each leg.
Four stability groups were derived: (1) stable on both legs (bilateral stability), (2) unstable on the throwing side leg (TS instability) and stable on the nonthrowing side leg, (3) unstable on the nonthrowing side leg (NTS instability) and stable on the throwing side leg, and (4) unstable on both legs (bilateral instability). All throws were analyzed across 4 throwing events: foot contact (FC), maximum external shoulder rotation (MER), ball release (BR), and maximum internal shoulder rotation (MIR).
Mann-Whitney U tests revealed significant differences between the bilateral stability and the TS instability groups in trunk flexion at BR; the bilateral stability and the NTS instability groups in trunk flexion at BR, shoulder horizontal abduction at FC, shoulder rotation at FC, and pelvis flexion at MIR; the TS instability and the bilateral instability groups in trunk rotation at FC; and the NTS instability and the bilateral instability groups in trunk flexion at MER and shoulder rotation at FC.
These findings demonstrate the different mechanisms in which energy can be lost through lumbopelvic-hip complex instability as evident in throwing mechanics. The findings from this study suggest that the current methods used for classification could act as a tool for coaches, physicians, and athletic trainers when assessing their athletes' injury susceptibility.
研究发现，在过顶投球过程中，腰骨盆-髋关节复合体产生的能量减少20%会导致肩部负荷增加34%。
本研究的目的是通过单腿深蹲评估来评估腰骨盆-髋关节复合体稳定性对垒球运动员投球力学的影响。
前瞻性队列研究。
实验室环境。
共有50名垒球运动员（身高164.0[104.0]厘米，体重65.6[11.3]千克，年龄16.3[3.8]岁，运动经验8.61[3.62]年）每条腿进行3次过顶投球和1次单腿深蹲。
分为四个稳定性组：（1）双腿稳定（双侧稳定），（2）投球侧腿不稳定（TS不稳定）且非投球侧腿稳定，（3）非投球侧腿不稳定（NTS不稳定）且投球侧腿稳定，（4）双腿不稳定（双侧不稳定）。对所有投球进行了4个投球事件的分析：脚接触（FC）、肩部最大外旋（MER）、球释放（BR）和肩部最大内旋（MIR）。
曼-惠特尼U检验显示，双侧稳定组与TS不稳定组在BR时的躯干屈曲、双侧稳定组与NTS不稳定组在BR时的躯干屈曲、FC时的肩部水平外展、FC时的肩部旋转以及MIR时的骨盆屈曲存在显著差异；TS不稳定组与双侧不稳定组在FC时的躯干旋转、NTS不稳定组与双侧不稳定组在MER时的躯干屈曲以及FC时的肩部旋转存在显著差异。
这些发现表明，在投球力学中，能量可因腰骨盆-髋关节复合体不稳定而以不同机制损失。本研究结果表明，当前用于分类的方法可作为教练、医生和运动训练师评估运动员受伤易感性的工具。
