Hughes R E, An K N
Mayo Clinic/Mayo Foundation, Rochester, MN 55905, USA.
Clin Orthop Relat Res. 1996 Sep(330):75-83. doi: 10.1097/00003086-199609000-00010.
A 3-dimensional static biomechanical model of the glenohumeral joint was used to investigate rotator cuff muscle forces during maximal isometric exertions (abduction, adduction, internal rotation, and external rotation) and static arm elevation. Muscle moment arms and cross sectional areas were determined from studies of cadaveric specimens, and maximal isometric strength data were collected using a Cybex II dynamometer. Predicted posterior deltoid forces were very low during abduction in the scapular plane. The model predicted the highest rotator cuff muscle forces during maximal internal rotation (subscapularis) and external rotation (infraspinatus, teres minor, and supraspinatus) exertions. The results indicate that abduction exertions may not produce the greatest loads on the supraspinatus tendon, and that analyses of arm elevation may underestimate the potential loads on the rotator cuff. The strong effect of external rotation exertions on supraspinatus and infraspinatus forces suggest that ergonomic efforts to prevent rotator cuff disease should include reduction of internal rotation loading on the arm. Moreover, it may be important to include warnings about external rotation exertions, in addition to arm elevation, in patient education.
使用肩肱关节的三维静态生物力学模型来研究在最大等长用力（外展、内收、内旋和外旋）及静态手臂抬高过程中肩袖肌的力量。肌肉力臂和横截面积通过对尸体标本的研究确定，最大等长力量数据使用Cybex II测力计收集。在肩胛平面外展过程中，预测的三角肌后束力量非常低。该模型预测在最大内旋（肩胛下肌）和外旋（冈下肌、小圆肌和冈上肌）用力时肩袖肌力量最高。结果表明，外展用力可能不会在冈上肌腱上产生最大负荷，并且手臂抬高分析可能低估了肩袖的潜在负荷。外旋用力对冈上肌和冈下肌力量的强烈影响表明，预防肩袖疾病的人体工程学措施应包括减少手臂的内旋负荷。此外，在患者教育中，除了手臂抬高外，可能还需要包含有关外旋用力的警告。
