Orthopaedic Biomechanics Laboratory, VA Long Beach Healthcare System and University of California, Irvine, CA, USA; Department of Orthopedic Surgery, Sungkyunkwan University College of Medicine, Samsung Medical Center, Seoul, South Korea.
Orthopaedic Biomechanics Laboratory, VA Long Beach Healthcare System and University of California, Irvine, CA, USA.
J Shoulder Elbow Surg. 2014 Jun;23(6):902-8. doi: 10.1016/j.jse.2013.09.015. Epub 2013 Dec 4.
With the advent of arthroscopy, more partial subscapularis tears are being recognized. The biomechanical effects of partial subscapularis tears are unknown, and there is no consensus as to their treatment. Therefore, the objective of this study was to evaluate and to quantify the changes in range of motion and glenohumeral kinematics for isolated subscapularis partial tears, combined subscapularis and supraspinatus tears, supraspinatus repair, and combined supraspinatus and subscapularis repair.
Six cadaveric shoulders were tested in the scapular plane with 0°, 30°, and 60° shoulder abduction under 6 conditions: intact; ¼ subscapularis tear; ½ subscapularis tear; ½ subscapularis and complete supraspinatus tear; supraspinatus repair; and supraspinatus and subscapularis repair. Maximum internal and external rotation and glenohumeral kinematics were measured under physiologic muscle loading condition. A repeated measures analysis of variance with a Tukey post hoc test was used for statistical analysis.
Maximum external rotation was significantly increased after ¼ subscapularis tear at 30° abduction and in all abduction angles with ½ subscapularis tear (P < .05). The 2 repair conditions did not restore external rotation to the intact level. At maximum internal and external rotation, there was a significant superior shift in the humeral head apex position with ¼ subscapularis tear at 30° abduction and with ½ subscapularis tear at 60° abduction (P < .05). Repair of the supraspinatus tendon partially corrected abnormal kinematics; however, neither repair restored abnormal kinematics to intact.
Additional repair of the partial subscapularis tear with supraspinatus tear did not affect external rotation or glenohumeral kinematics. Further studies are needed to evaluate different subscapularis repair techniques.
Basic science study, biomechanics.
随着关节镜技术的出现，越来越多的肩胛下肌部分撕裂被发现。肩胛下肌部分撕裂的生物力学影响尚不清楚，其治疗也没有共识。因此，本研究的目的是评估和量化孤立性肩胛下肌部分撕裂、肩胛下肌和冈上肌联合撕裂、冈上肌修复以及肩胛下肌和冈上肌联合修复后的运动范围和盂肱关节运动学的变化。
在肩胛骨平面下，对 6 具尸体肩关节在 0°、30°和 60°肩关节外展下进行测试，共 6 种情况：完整、肩胛下肌四分之一撕裂、肩胛下肌二分之一撕裂、肩胛下肌和完整冈上肌撕裂、冈上肌修复、冈上肌和肩胛下肌修复。在生理肌肉负荷条件下测量最大内旋和外旋以及盂肱关节运动学。采用重复测量方差分析和 Tukey 事后检验进行统计学分析。
四分之一肩胛下肌撕裂时，30°外展时和所有外展角度的最大外旋均显著增加（P <.05）。两种修复情况均未使外旋恢复到完整水平。在最大内旋和外旋时，四分之一肩胛下肌撕裂时 30°外展时和二分之一肩胛下肌撕裂时 60°外展时，肱骨头顶点位置有明显的上移（P <.05）。冈上肌腱修复部分纠正了异常运动学，但两种修复均未使异常运动学恢复到完整水平。
伴有冈上肌撕裂的肩胛下肌部分撕裂的附加修复并不影响外旋或盂肱关节运动学。需要进一步研究不同的肩胛下肌修复技术。
基础科学研究，生物力学。
