The Stabilizing Sling for the Long Head of the Biceps Tendon in the Rotator Cuff Interval

Abstract

A histoanatomic study of the rotator cuff interval was done in 13 cadaveric specimens to investigate the relation of its ligamentous structures to the long head of the biceps tendon, with a special focus on revealing a stabilizing function. After macroscopic evaluation, the lateral half of the rotator cuff interval capsule was cut into three sections: medial, middle, and lateral. These sections were embedded in methacrylate, and then serial sections were made and stained for polarized light microscopy. The superior glenohumeral ligament was seen to form a fold having the macroscopic appearance of a U-shaped anterior suspension sling for the long head of the biceps tendon. Microscopic evaluation revealed an important role of the fasciculus obliquus in the roof of this sling. Fibers of the supraspinatus tendon join the posterosuperior part of the sling. The subscapularis tendon is not involved in this suspensory mechanism. As a result of these observations, we determined that the superior glenohumeral ligament and the fasciculus obliquus are the most important ligamentous reinforcements of a stabilizing sling for the long head of the biceps tendon in the rotator cuff interval. Their histologic appearance indicates they function to protect the long head of the biceps against anterior shearing stress. A lesion of this sling might lead to anterior instability of the biceps tendon.

Disorders of the long head of biceps tendon

“…The exact location of labral attachment varies, but is usually in the posterior portion of the superior labrum. 18,60 The intra-articular portion of the LHB tendon is partially stabilized by the biceps reflection pulley, which consists of the superior glenohumeral ligament (SGHL), the coracohumeral ligament, and deep fibers of the subscapularis and supraspinatus tendons 64 (Fig. 1).…”

Variations in the superior capsuloligamentous complex and description of a new ligament

“…2,21,98 We believe that the coracoglenohumeral ligament inserts onto both margins of the groove together with the anterior limb of the rotator cable. The tendons of the supraspinatus and of the subscapularis rarely cover the groove.…”

“…Furthermore, the superior and inferior complexes may be linked to each other medially, through the glenoid labrum, as well as laterally, through the fasciculus obliquus. Werner et al 98 already reported that the fasciculus obliquus makes an important contribution to the biceps pulley together with the superior glenohumeral ligament. The potential implications of the superior complex and the linkage between both complexes for glenohumeral stability require further study.…”

“…The tendons of the supraspinatus and of the subscapularis rarely cover the groove. Werner et al 98 reported that the fasciculus obliquus makes an important contribution to the biceps pulley together with the superior glenohumeral ligament. Lesions of the so-called biceps pulley may be destabilizing for 2 reasons: either because the long tendon of the biceps may subluxate or because the head-depressing effect of the rotator cable is diminished.…”

Arthroskopische Rekonstruktion der Subscapularissehne

“…Rotatoreninter vallschlinge ("reflection pulley") verläuft. Diese Schlinge wird zum einen aus dem coracohumeralen Band (CHL), das von der Basis und der lateralen Facette des Coracoids zum Vorderrand des M. su praspinatus und mit zwei Schenkeln am Tuberculum minus und majus inseriert, und zum anderen vom superioren gleno humeralen Band (SGHL) gebildet, das aus dem kapsulären Ansatzbereich des Tuber culum supraglenoidale entspringt und als kapsuläres Verstärkungsband Uförmig unterhalb der langen Bizepssehne zum Oberrand des Tuberculum minus zieht [32]. Das SGHL und das CHL bilden so eine Schlinge aus, die wie ein Ringband die lange Bizepssehne sichert, noch bevor diese in den Sulcus bicipitalis eintaucht.…”