抄録
In order to clarify the function of the rotator cuff as the dynamic stabilizer, intraarticular lesions in rotator cuff tears were observed in 52 shoulder joints of 26 cadavers. The glenoid labrums in 33 shoulder joints without cuff tears consisted of circumferentially oriented fibrous structure. The angular values of the labrums were 23.9° ± 5.6 (average± SD)in the superior portion,11.2° ± 4.3 in the inferior portion,9.2° ± 2.8 in the anterior portion, and 10.8° ± 3.2 in the posterior portion. On the other hand, the pathological changes of the glenoid labrum and intra-articular portion of the bicipital long tendon were recognized in all of the shoulder joints with cuff tears (19 joints). In the incomplete tears (12 joints), progressive hypertrophy was observed in the anterosuperior portion of the labrum. In the small or moderate tears (3 joints), hypertrophy and fraying were recognized from the anterosuperior to the anteroinferior portion. In the massive tears (4 joints), these pathological changes were extended all over the labrum. The intra-articular portion of the bicipital long tendon was slightly thickened in the incomplete tears, very thickened and widened in the small and moderate tears, and frayed, dislocated and ruptured in the massive tears.
As obvious intra-articular lesions were recognized, even in the inc o mplete and small cuff tears, we conclude that the rotator cuff plays a significant role of glenohumeral stabilizer associated with intra-articular elements, such as the glenoid labrum and the bicipital long tendon.
