存在盂肱關節內轉缺失的高中棒球投手之肩胛骨運動學與肌肉活性

The scapular kinematics and muscle activation in high school baseball pitchers with glenohumeral internal rotation deficit

翁義軒(Yi-Hsuan Weng)

指導教授 ： 林居正

國立臺灣大學/醫學院/物理治療學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201903246

摘要

背景：普遍認為過肩投擲和擊球的動作特質和產生傷害的機制有關，特別在重複動作的特質之下，投手的肩膀會產生活動度上的適應性變化，包括在盂肱關節的外轉增加和內轉減少，這些適應性變化就和傷害的發生息息相關。盂肱關節內轉缺失(GIRD)是造成肩膀傷害的危險因子之一，此外，他還跟肩胛骨運動的轉變有關，但我們仍不了解他在各投球時期對肩胛骨運動學的影響。實驗目的：本篇研究的目的在於比較無症狀且無內轉缺失(AswG)、無症狀但有內轉缺失(AsG)及有症狀且有內轉缺失(SG)三種類型的棒球投手，在投擲直球時之肩胛骨運動學與肌肉活性。實驗設計：來自台北市與新北市青棒隊的高中棒球投手透過教練推薦參與實驗，AswG、AsG、SG三種類型的選手將會被納入實驗。每位受試者都會進行肩關節活動度的測量及關節囊鬆緊度的檢測，貼上感應器後則使用三維電磁動作追蹤系統及表面肌電圖收取投擲直球時肩胛骨運動學及肌肉活性的資料。主要測量項目：本篇研究的主要測量項目為肩胛骨運動學(上/下轉、前/後傾、內/外轉)及肌肉活性(上斜方肌、下斜方肌、前鋸肌、前三角肌、肱二頭肌、肱三頭肌)結果：針對肩胛骨內外轉部分，統計發現有交互作用(p<0.05)，AsG組在肩關節最大外轉及出手時相較於AswG組有較少的外轉，然而在抬腿最高時，SG組卻相較於AsG組有較多的外轉；針對肩胛骨上下轉部分，AsG組相較於AswG組有較少的上轉；在肩胛骨前後傾的部分，AsG組及SG組都相較於AswG組有較多的前傾。在肌肉活性的部分，AsG組相較於AswG組在加速期有較高的前三角肌活性；在揮臂前期及加速期SG組相較於AsG組有較低的肱三頭肌活性，而此時期AsG組則高於AswG組；在揮臂前期及揮臂後期，SG組相較於AsG組有較低的前鋸肌活性，而此時期AsG組則高於AswG組。結論：有盂肱關節內轉缺失的選手在肩胛骨運動學上有轉變，他們會試著用肌肉來代償這樣的轉變但效果不顯著。

關鍵字

盂肱關節內轉缺失 ； 棒球 ； 肩胛骨運動學 ； 肌肉活性 ； 肩膀傷害

並列摘要

Background: The characteristics of overhead throwing and striking tasks were believed to be related to the mechanism of injury. As a repetitive nature of sports throwing, pitchers' shoulder had developed a range of motion adaptation, including increased external rotation and decreased internal rotation in the glenohumeral joint at 90° of abduction in the throwing shoulder. These adaptations were highly related to injury occurrence. Glenohumeral internal rotation deficit (GIRD) was believed to be one of the risk factors contributing to shoulder injury. Additionally, it’s associated with altered scapular kinematics. However, it was not clear how these alternations related to specific phases of the pitching motion. Objective: The objective of the present study was to compare the scapular kinematics and muscle activity in asymptomatic baseball pitchers without GIRD (AswG), asymptomatic baseball pitchers with GIRD (AsG), and symptomatic baseball pitchers with GIRD (SG) during fast ball pitching. Design: High school pitchers were recruited from high schools in Taipei city and New Taipei city. They were recruited from 3 groups, the AswG group, AsG group, and SG group. Each subject underwent an assessment of the glenohumeral range of motion and capsular tightness. Then, three-dimensional electromagnetic motion analysis and electromyography muscle activity were used to record the scapular kinematics and absolute muscle activation during fast ball pitching. Main outcome measures: Scapular kinematics (upward/downward rotation, anterior/posterior tilt, external/internal rotation) and absolute muscle activation (upper trapezius, lower trapezius, serratus anterior, anterior deltoid, biceps brachii, and triceps brachii) were main outcomes of the study. Results: For the scapular external/internal rotation, there was an interaction effect (p<0.05). The AsG group was significantly decreased external rotation than the AswG group at maximum external rotation and ball release (15.3° and 18.5°, p=0.029 and 0.022, respectively). However, at the time of the lead leg at the highest point, the SG group was significantly increased external rotation than the AsG group (2.9°, p=0.043). For the scapular upward/downward rotation, the AsG group had decreased upward rotation about 14.3° compared with the AswG group (p=0.033). For scapular anterior/posterior tilt, the AsG group had increased anterior tilt than the AswG group in each phase (6.8°, 15.0°, 18.4°, and 17.3°, p=0.002, 0.008, 0.001 and 0.005, respectively). Also, the SG group had increased anterior tilt than the AswG group (4.1°, 12.2°, 14.5°, and 13.7°, p= 0.044, 0.027, 0.009 and 0.022, respectively). For muscle activities, the AsG group had higher muscle activity than the AswG group in anterior deltoid during the acceleration phase (26.4%, p=0.031). In triceps brachii muscle, the SG group had lower muscle activity than the AsG group during early-cocking and acceleration phase (8.8% and 37.8%, p=0.028 and 0.016, respectively). Otherwise, the AsG group had higher triceps brachii muscle activity than the AswG group during early-cocking and acceleration phase (9.9% and 36.8%, p=0.015 and 0.018, respectively). In serratus anterior muscle, the SG group had lower muscle activity than the AsG group during early-cocking and late-cocking phase (4.8% and 30.2%, p=0.004 and 0.007, respectively). Instead, the AsG group had higher serratus anterior muscle activity than the AswG group during early-cocking and late-cocking phase (3.7% and 30.8%, p=0.018 and 0.006, respectively). Conclusions: Subjects with GIRD had scapular kinematics alteration. They tried to compensate for the deficits by muscle activation, but the effect was limited.

並列關鍵字

glenohumeral internal rotation deficit ； baseball ； scapular kinematics ； muscle activation ； shoulder injuries

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