Test your knowledge: long head of the biceps.
Are these statements regarding the shoulder joint true or false?
A. The origin of the tendon of the long head of the biceps muscle is always situated inside the joint cavity, only surrounded by a synovial layer.
B. The transverse ligament is a part of the subscapular muscle.
C. The tendon of the long head of the biceps can luxate over the major tubercle to the lateral.
D. Chronic impingement can lead to an avascular part of the supraspinatus tendon which is an important risk for partial or complete tearing of the tendon.
E. The flat type acromion is the most common acromion type and is commonly associated with rotator cuff tears.
F. The tendon of the supraspinatus consists of a thicker posterior part and a thinner anterior part and is fused with the capsule of the shoulder.
G. The rotator cuff interval is the space between the supraspinatus and infraspinatus tendon.
The answers can be read underneath the picture below.
The origin of the long head of the biceps tendon is always intra articular (A right). The more distal part of the tendon may not be free inside the joint cavity but situated between the synovia land fibrous layers of the capsule. Its origin is seldom exclusively on the supraglenoid tubercle, but generally also on the labrum, mainly the posterior part.
The space between the supraspinatus and subscapular tendon is called the rotator cuff interval (G false). This is the place where the tendon of the long head of the biceps comes out of the intertubercular sulcus and courses in an angle to the supraglenoidal tubercle and the labrum. The long head of the biceps tendon is covered by the transverse ligament when it passes the intertubercular sulcus. One of the attachment places of the subscapular tendon(s) is at this ligament (B false). A rupture of this ligament can lead to subluxation of the long head of the biceps out of the intertubercular sulcus over the tubercle minor (C false) into the subscapularis muscle.
The suprapinatus tendon is another important structure in the shoulder in which a lot of pathologies can be found. Chronic compression through subacromial impingement can lead to a loss of vascularity of a part of the supraspinatus tendon called ‘the critical zone’ in the thicker anterior part (F false) of the tendon. This can lead to multiple calcifications or partial or even complete, full thickness tears (D right) of the tendon. A hooked acromion type (E false) is one of the main primary causes of impingement pathologies in the subacromial part of the shoulder. It leads to a loss of the vascularity in the tendon mentioned above.