Proximal part

Figure 1. Ventral view, transverse plane. b: tendon of the long head of biceps brachii, ssc: tendon of subscapularis.

In the intertubercular sulcus of the humerus lies the tendon of the long head of biceps brachii (b), which appears as a well-demarcated oval hyperechoic fibrillar structure. Around the tendon, a thin hypoechoic rim of the synovial sheath is visible. The greater tubercle is shown laterally, the lesser tubercle medially. At the medial edge of the sulcus, part of the tendon of subscapularis (ssc) is visible, inserting on the lesser tubercle of the humerus. Superficially lies the deltoid muscle.

Figure 2. Ventral view, transverse plane. LHBB: muscle belly of the long head of biceps brachii, SHBB: muscle belly of the short head of biceps brachii

A more distal transverse ultrasound section of the anterior arm shows the muscle bellies of both heads of biceps brachii. The long head (LHBB) is located laterally, the short head (SHBB) medially. The deltoid muscle is positioned superficially, and the proximal humerus is visible deep. This projection is suitable for evaluating the integrity of muscle tissue, mutual symmetry of both biceps heads, and dynamic muscle contraction.

Figure 3. Ventral view, transverse plane. LH: long head of biceps brachii, SH: short head of biceps brachii

A more medial and proximal transverse ultrasound section of the anterior shoulder shows the short head of biceps brachii (SH) as a round hypoechoic structure located beneath the deltoid muscle and medial to the long head (LH). The short head here extends toward its origin in the region of the coracoid process. The deltoid muscle is located superficially, while the proximal humerus is visible deep. This projection is important for complete evaluation of the proximal anatomy of the biceps and for distinguishing isolated involvement of the short and long heads.

Figure 4. Ventral view, longitudinal plane. LHBB tendon: long head of biceps brachii tendon

The longitudinal ultrasound section of the anterior shoulder region shows the long head of biceps brachii tendon as a hyperechoic fibrillar structure running in the intertubercular sulcus of the humerus. The bony walls of the sulcus are formed by the cortical margins of the tuberculum majus and tuberculum minus, which provide reliable anatomical orientation. The deltoid muscle is located superficially. In this projection, we primarily evaluate the continuity, contour and thickness of the tendon, as well as the potential presence of fluid in the sheath.

Figure 5. Ventral view, longitudinal plane. LHBB: long head of biceps brachii muscle

Longitudinal ultrasound section of the anterior part of the shoulder in the area of the myotendinous junction of the long head of biceps brachii muscle. A smooth transition from tendon to muscle belly is evident, representing a change from the hyperechoic fibrillar structure of the tendon to hypoechoic muscle tissue with fine striated architecture. The deltoid muscle is located superficially, and the humerus is visible deep.

Figure 6. Ventral view, longitudinal plane. SHBB: short head of m. biceps brachii, cor: processus coracoideus

The longitudinal ultrasound section of the anterior part of the shoulder displays the short head of m. biceps brachii (SHBB) running proximally to its origin on the processus coracoideus of the scapula (cor). The muscle appears as a hypoechoic structure with fine striated architecture, adjacent to the cortical surface of the coracoid. The m. deltoideus is located superficially. This projection is useful for differentiating the short and long heads of the biceps and for evaluating the area in cases of proximal biceps pain or suspected traumatic avulsion injury.

Figure 7. Ventral view, longitudinal plane. SHBB: short head of biceps brachii muscle

Longitudinal ultrasound section of the anterior part of the arm in the region of the myotendinous junction of the short head of biceps brachii muscle (SHBB). A smooth transition of tendon fibers into the proximal muscle belly is visible, which has homogeneous echogenicity and fine striated architecture. The deltoid muscle is located superficially. In this projection, we primarily evaluate the continuity and structure of the myotendinous junction.