McHugh Malachy P, Mullaney Michael J
Nicholas Institute of Sports Medicine and Athletic Trauma.
Int J Sports Phys Ther. 2023 Aug 2;18(4):949-957. doi: 10.26603/001c.81596. eCollection 2023.
The flexor carpi ulnaris (FCU) and flexor digitorum superficialis (FDS) are thought to provide dynamic stability to the medial elbow, with a lesser contribution from the pronator teres (PT).
HYPOTHESIS/PURPOSE: The purpose of this study was to determine if baseball pitchers with higher valgus elbow torque experience greater FCU and FDS strength loss.
Controlled Laboratory Study.
A pilot study was performed to determine if middle and ring finger flexion strength tests preferentially activated the FCU and FDS versus the PT (10 men age 36±12 yr). EMG amplitudes, expressed as percent of maximal voluntary contraction (MVC) were compared between tests and muscles. In a field study of college baseball pitchers, middle finger, ring finger and grip strength were tested prior to, immediately after, and one day after 14 pitching performances in 10 pitchers (21±2 yr). Elbow valgus torque was measured from an inertial measurement unit, housed in a compression sleeve and pitchers were categorized as having high or low valgus torque.
For the pilot study EMG activations were 74% FDS, 66% FCU and 35% PT for the middle finger test (muscle effect p=0.032) and 93% FCU, 61% FDS and 23% PT for the ring finger test (muscle effect p=0.005). In the field study, pitchers with high valgus torque showed marked post-game middle finger fatigue (88% of baseline) and incomplete recovery the following day (95%), while pitchers with low valgus torque showed no strength loss (107% post game, 106% a day later; group x time p=0.022). Results were similar for ring finger strength (high torque: 94% post game 96% a day later; low torque: 114% post game 107% a day later; group x time p=0.048). By contrast, grip strength was not different between pitchers with high versus low valgus torque (p=0.143).
High medial elbow stress during pitching fatigues the dynamic stabilizers of the medial elbow.
Level 3©The Author(s).
尺侧腕屈肌（FCU）和指浅屈肌（FDS）被认为可为内侧肘部提供动态稳定性，旋前圆肌（PT）的作用较小。
假设/目的：本研究的目的是确定肘部外翻扭矩较高的棒球投手是否会出现更大程度的尺侧腕屈肌和指浅屈肌力量损失。
对照实验室研究。
进行一项初步研究，以确定中指和环指屈曲力量测试是否优先激活尺侧腕屈肌和指浅屈肌而非旋前圆肌（10名年龄36±12岁的男性）。比较测试与肌肉之间以最大自主收缩（MVC）百分比表示的肌电图（EMG）幅度。在一项针对大学棒球投手的现场研究中，对10名投手（21±2岁）在14次投球表现之前、之后立即以及一天后的中指、环指和握力进行了测试。通过置于压缩袖套中的惯性测量单元测量肘部外翻扭矩，并将投手分为高或低外翻扭矩组。
在初步研究中，中指测试的肌电图激活情况为指浅屈肌74%、尺侧腕屈肌66%、旋前圆肌35%（肌肉效应p = 0.032），环指测试为尺侧腕屈肌93%、指浅屈肌61%、旋前圆肌23%（肌肉效应p = 0.005）。在现场研究中，高外翻扭矩的投手赛后中指明显疲劳（为基线的88%）且次日恢复不完全（95%），而低外翻扭矩的投手则没有力量损失（赛后107%，一天后106%；组×时间p = 0.022）。环指力量的结果相似（高扭矩：赛后9俯%，一天后96%；低扭矩：赛后114%，一天后107%；组×时间p = 0.048）。相比之下，高、低外翻扭矩投手的握力没有差异（p = 0.143）。
投球过程中内侧肘部的高应力会使内侧肘部的动态稳定肌疲劳。
3级。©作者。
