Bailey Lane B, Shanley Ellen, Hawkins Richard, Beattie Paul F, Fritz Stacy, Kwartowitz David, Thigpen Charles A
Department of Sports Medicine and Rehabilitation, Memorial Hermann's Ironman Sports Medicine Institute, Houston, Texas, USA
Department of Rehabilitation and Reconstruction Sciences, Carolina Center for Economic Excellence, Greenville, South Carolina, USA ATI Physical Therapy, Greenville, South Carolina, USA.
Am J Sports Med. 2015 Nov;43(11):2783-93. doi: 10.1177/0363546515602446. Epub 2015 Sep 24.
Shoulder range of motion (ROM) deficits have been identified as injury risk factors among baseball athletes. Despite the knowledge surrounding these risk factors, there is a lack of consensus regarding the specific tissues responsible for these deficits in ROM.
PURPOSE/HYPOTHESIS: The purpose of this study was to elucidate the primary mechanisms of posterior shoulder tightness (capsular, musculotendinous, bony) by examining the tissue responses that occur with the application of an acute intervention in baseball players with ROM deficits. The hypothesis was that posterior rotator cuff stiffness, not glenohumeral joint mobility, would be primarily responsible for ROM gains observed within an acute treatment setting.
Controlled laboratory study.
Through use of ultrasound elastography, electromagnetic motion analysis, and ultrasound imaging, posterior rotator cuff stiffness, glenohumeral joint translation, and humeral torsion were examined in 60 asymptomatic baseball players (age, mean ± SD, 19 ± 2 years) with shoulder ROM deficits. Tissue mechanisms were examined concurrently, with the ROM gains elicited by an acute application of instrument-assisted soft tissue mobilization plus self-stretching (n = 30) versus self-stretching only (n = 30). Separate 3-way analyses of variance (group × arm × time) and linear regression analyses were used to determine the treatment effects and relationships between tissue mechanisms and ROM gains.
ROM gains were associated with decreases in rotator cuff stiffness (internal rotation: r = 0.35, P = .034; horizontal adduction: r = 0.44, P = .008) and increased humeral retrotorsion (internal rotation: r = -0.35, P = .034), not joint translation (P > .05). Players receiving instrument-assisted soft tissue mobilization plus stretching displayed greater shoulder ROM gains (internal rotation, +5° ± 2° [P = .010]; total arc of motion, +8° ± 6° [P = .010]; horizontal adduction, +7° ± 2° [P = .004]; and decreased posterior rotator cuff stiffness, -0.2 ± 0.3 kPa [P = .050]) compared with players receiving self-stretching alone.
Decreases in rotator cuff stiffness were associated with acute ROM gains in baseball players. The study results show that changes in rotator cuff stiffness, not glenohumeral joint mobility or humeral torsion, are most likely associated with the ROM deficits observed in adolescent baseball players.
Reducing rotator cuff stiffness may be beneficial in improving the ROM deficits associated with injury risk in overhead athletes.
肩部活动范围（ROM）不足已被确定为棒球运动员的损伤风险因素。尽管对这些风险因素有所了解，但对于导致ROM不足的具体组织尚无共识。
目的/假设：本研究的目的是通过检查对ROM不足的棒球运动员进行急性干预时发生的组织反应，阐明肩部后方紧绷（关节囊、肌腱、骨骼）的主要机制。假设是在急性治疗环境中观察到的ROM增加主要是由肩袖后束僵硬而非盂肱关节活动度引起的。
对照实验室研究。
通过使用超声弹性成像、电磁运动分析和超声成像，对60名肩部ROM不足的无症状棒球运动员（年龄，平均±标准差，19±2岁）的肩袖后束僵硬、盂肱关节平移和肱骨扭转进行了检查。同时检查组织机制，将器械辅助软组织松动加自我拉伸（n = 30）与仅自我拉伸（n = 30）急性应用引起ROM增加的情况进行比较。使用单独的三因素方差分析（组×臂×时间）和线性回归分析来确定治疗效果以及组织机制与ROM增加之间的关系。
ROM增加与肩袖僵硬程度降低（内旋：r = 0.35，P = 0.034；水平内收：r = 0.44，P = 0.008）和肱骨后扭转增加（内旋：r = -0.35，P = 0.034）相关，而非关节平移（P>0.05）。与仅接受自我拉伸的运动员相比，接受器械辅助软组织松动加拉伸的运动员肩部ROM增加更大（内旋，+5°±2°[P = .010]；总运动弧度，+8°±6°[P = .010]；水平内收，+7°±2°[P = .004]；肩袖后束僵硬程度降低，-0.2±0.3 kPa [P = .050]）。
肩袖僵硬程度降低与棒球运动员急性ROM增加相关。研究结果表明，肩袖僵硬程度的变化而非盂肱关节活动度或肱骨扭转，最有可能与青少年棒球运动员中观察到的ROM不足相关。
降低肩袖僵硬程度可能有助于改善与上肢运动员损伤风险相关的ROM不足。
