Transverse humeral ligament

At a glance

English

Transverse humeral ligament

Latin (TA2)

Ligamentum transversum humeri

System

Ligament

Region

Upper limb

Side

Paired, left and right

About the transverse humeral ligament

On the front of the upper humerus a vertical groove, the intertubercular (bicipital) groove, separates the greater tubercle from the lesser tubercle. The tendon of the long head of biceps brachii runs down this groove, wrapped in a sleeve of synovial membrane from the shoulder joint. Across the top of the groove is a band of transverse fibres, the transverse humeral ligament, sometimes called Brodie's ligament.

The ligament is a broad, short sheet that spans from the lesser tubercle to the greater tubercle. Its attachments stay above the epiphysial line of the humerus, near the upper end of the groove. By roofing over the groove it turns it into a canal through which the tendon and its synovial sheath slide. Many anatomists now regard the band less as a separate ligament and more as a continuation of fibres from the subscapularis tendon and the coracohumeral ligament, which cross the groove to reach the greater tubercle. Below it, the groove is covered by the tendon of pectoralis major, whose insertion runs along the lateral lip.

The ligament's job is to keep the long head of biceps inside its groove while the arm rotates and moves, so that the tendon acts as a pulley over the humeral head and helps press it into the glenoid.

If the ligament or the surrounding soft-tissue sling is torn or weak, the tendon can slip medially over the lesser tubercle, especially during forceful lateral rotation, causing a painful snap at the front of the shoulder. Such subluxation of the biceps tendon is usually accompanied by a tear of subscapularis. Inflammation of the tendon in the groove, bicipital tendinitis, gives tenderness over this point. In chronic cases surgeons may cut the tendon or reattach it lower down.

Attachments and function

Attaches from

The lesser tubercle of the humerus.

Attaches to

The greater tubercle of the humerus, above the epiphysial line.

Function

Roofs over the intertubercular groove, keeping the tendon of the long head of biceps and its sheath within it.

Nerve supply

Twigs of the axillary nerve to the shoulder region.

Blood supply

The ascending branch of the anterior circumflex humeral artery, which runs up the groove.