Axillary Sonography of the Shoulder: An Adjunctive Approach.

Sonography of the shoulder is widely used to assess various disorders, including tendinous diseases of the rotator cuff and the long head of the biceps brachii muscle. The shoulder is commonly explored through anterior, superior, and posterior approaches, but the inferior axillary approach is rarely considered in the literature. However, this technique allows the direct visualization of relevant anatomic structures. The aim of this pictorial essay is, first, to technically describe this approach and the normal musculoskeletal sonographic anatomy of the region and, second, to present the sonographic findings of shoulder disorders that may be helpfully explored this technique.