Collagen Fiber Arrangement of the Human Shoulder Joint Capsule – An Anatomical Study

Abstract

The polariscopic examination of isolated shoulder joint capsules shows that the entire capsule does not have a homogeneous collagen structure. Most of the capsule is characterized by regular collagen fibers which cross at an obtuse angle in the area of the musculus supraspinatus and at an acute angle in the area of the m. inf raspinatus. The density of the collagen network increases from the medial to the lateral part. Deviating from this basic pattern of the joint capsule, there is a different collagen texture in the area between the m. supraspinatus and the m. subscapularis. This texture has dissociated rarefied and irregular collagen fibers. This means that the area – in comparison with the remainder of the capsule – is characterized not only by missing reinforcing ligaments but also by a deviating pattern of the collagen fibers. This different collagen structure is already existent in the fetus.

Functional morphology of the supraspinatus tendon

“…Our findings regarding this structure are in agreement with thosc Clarke and Harryman [9], Burkhart et al [7], and Gohlke et al [13]. Our findings of thejoint capsule agree with those of Gohlke et al [13], and Steiner and Hermann [24].…”

Histologic Evaluation of the Shoulder Capsule in Normal Shoulders, Unstable Shoulders, and after Failed Thermal Capsulorrhaphy

“…Our results confirm those of previous studies regarding the structure and histologic appearance of the normal shoulder capsule. 6,9,30 Previous studies have shown that this basic structure is histologically consistent, regardless of the area sampled, although thickenings in the collagen layer of the capsule create ligaments that may make this layer thicker. 6,22 Other studies have suggested that the collagen bands have different configurations in different portions of the capsule, depending on the location and function of the capsule in that area.…”

“…6,22 Other studies have suggested that the collagen bands have different configurations in different portions of the capsule, depending on the location and function of the capsule in that area. 6,22,30…”

Early fetal development of the rotator interval region of the shoulder with special reference to topographical relationships among related tendons and ligaments

“…Arai 3 recently detailed the morphology of the supportive structures for the biceps long tendon, such as the superior glenohumeral ligament. However, there is little or no information on the fetal topographical anatomy of the rotator interval region of the shoulder because the majority of previous studies have focused on histogenetic aspects, such as collagen fiber maturation, rather than anatomy [4][5][6][7] . Does the subscapularis tendon or the biceps tendon modify the primitive morphology of the interval during the early development?…”