The biceps muscle has two heads, a long head and a short head, which attach to the scapula via individual tendons. Pathology commonly affects the long head, which is generally referred to as the biceps tendon. The long head of the biceps originates from the supraglenoid tubercle, labrum, and the joint capsule. It then passes through the triangular space between the tendons of the subscapularis and supraspinatus muscles called the rotator cuff interval. Here, the biceps tendon is stabilized by the coracohumeral ligament and superior glenohumeral ligament. As the biceps tendon travels distally it remains in a synovial sheath, shared with the anterior circumflex artery, for approximately 3–4 cm. As the biceps tendon reaches the proximal humerus, it courses through the intertubercular groove (also called the bicipital groove ) between the greater tuberosity (lateral) and the lesser tuberosity (medial). At this position, it is stabilized in the bicipital groove by the overlying transverse humeral ligament.

Bicipital tenosynovitis is most often secondary to impingement beneath the coracoacromial arch near the bicipital groove but may also occur secondary to instability. Fluid within the sheath is considered abnormal and may occur with localized tenosynovitis. However, the origin of the biceps tendon is intraarticular, thus effusions as a result of intraarticular pathology, such as glenohumeral osteoarthritis or rotator cuff tear, may leak into the biceps tendon sheath.

Biceps tendon sheath injections can be considered for patients with anterior shoulder pain that localizes to the biceps tendon region with accompanying ultrasound findings of tenosynovitis or effusion. This chapter will describe an in-plane technique, short axis to the biceps tendon at the level of the bicipital groove, with out-of-plane confirmation. Safety considerations will also be highlighted, including the use of Doppler imaging to avoid anterior circumflex artery injection.