Coracohumeral ligament (CHL) is situated in the gap between the supraspinatus and the subscapuralis. There are only a few studies concerning the CHL after Clark and Harryman II (1992) in spite of the important role that fills the rotator interval. In this study, we dissected six shoulders of three cadavers to observe the spatial distribution of the CHL in detail. Four shoulders of two cadavers were processed to analyze the attachment of the rotator cuff and the capsule histologically. For the histological analyses, whole parts of the CHL were removed emblock, and serial sections were made from proximal to distal. In gross anatomy, the CHL attached to the proximal lateral surface of the coracoid process in its most proximal part. It filled the rotator interval between the supraspinatus and the subscapularis. Most distal part of the CHL extended to both the superior and inferior surfaces of supraspinatus, and both the anterior and posterior surfaces of subscapularis. In the rotator interval, CHL connected to the superior glenohumeral ligament (SGHL). There was no clear border between the CHL and the SGHL in either gross anatomy or histologically. Histologically, the CHL contained only fine loose slack collagen fibers without any dense fiber that is normally observed in a ligament. With flexion and the extension, the CHL were stretched to pull the rotator interval. From these observations, the CHL seems to work with the SGHL for the stability of the long head of the biceps during shoulder movement.
