Caruana Ethan, Wigderowitz Carlos, Harrold Fraser
Department of Orthopaedic and Trauma Surgery, Tayside Orthopaedic Rehabilitation Technology (TORT) Centre, Postgraduate Division, School of Medicine, Ninewells Hospital and Medical School, University of Dundee, Scotland, UK.
Shoulder Elbow. 2019 May;11(1 Suppl):26-29. doi: 10.1177/1758573217736027. Epub 2018 Jan 22.
The objective of the present study was to determine the size and position of the rotator cuff moment arms constructed from the cuff footprints, incident on the line of force acting through the humeral head.
Five humeri were dissected, leaving the footprints of the rotator cuff intact. Each of the rotator cuff footprints and the cartilage/calcar interface were digitized and the articular surface was scanned using a high precision surface laser scanner. All of the data were merged into the same coordinate system. The centroid of each cuff footprint, centroid of the articular surface of the humerus (G) and the centroid of the articular surface of the glenoid (P) were calculated. Moment arms were measured as the intersection of a perpendicular line of force from each footprint centroid onto the resultant line of force to the centroid of the Glenoid (P).
The mean moment arms of the supraspinatus, infraspinatus and subscapularis muscles were incident close to the centroid (G), whereas teres minor was lateral to the centroid, consistently.
The teres minor moment arm aligned distal to the centroid of the sphere, consistently. The results may provide an understanding of the function of each muscle as a mobilizer or stabilizer of the glenohumeral joint. Further investigation is necessary.
本研究的目的是确定从肩袖足迹构建的肩袖力矩臂的大小和位置，这些力矩臂作用于通过肱骨头的力线上。
解剖五具肱骨，保留肩袖的足迹。使用高精度表面激光扫描仪对每个肩袖足迹以及软骨/距状突界面进行数字化处理，并扫描关节表面。所有数据都合并到同一个坐标系中。计算每个肩袖足迹的质心、肱骨关节面的质心（G）和肩胛骨关节面的质心（P）。力矩臂的测量方法是，从每个足迹质心向通过肩胛骨关节面质心（P）的合力线作垂线，该垂线与合力线的交点即为力矩臂。
冈上肌、冈下肌和肩胛下肌的平均力矩臂靠近质心（G），而小圆肌的平均力矩臂始终位于质心外侧。
小圆肌的力矩臂始终位于球体质心的远侧。这些结果可能有助于理解各肌肉作为盂肱关节活动器或稳定器的功能。有必要进行进一步研究。
