Posterior Full Body View of the Latissimus Dorsi

Description

Spanning the posterior trunk, the paired latissimus dorsi (lats) form broad muscular sheets that sweep superolaterally from the thoracolumbar fascia and lower thoracic spinous processes toward the posterior axillary fold and proximal humerus. Medially, the fibers approach the vertebral column; laterally, they border the flank and overlie the posterior ribs before converging into a tendon that passes anterior to teres major to insert on the floor of the intertubercular sulcus (bicipital groove). The scapulae sit superior and lateral to the muscle bellies, while the iliac crests and posterior pelvis provide an inferior bony landmark for the muscle’s lower extent. Skeleton-through context clarifies how far the latissimus reaches. Functionally, this posterior full-body perspective is the one you want when teaching shoulder extension, adduction, and internal rotation in anatomical position, because it shows how a trunk muscle can act on the glenohumeral joint through its humeral insertion. The relationship to the inferior angle of the scapula and the posterior axillary fold matters in surgery: during axillary lymph node dissection, the thoracodorsal nerve and vessels run on the deep surface of the latissimus dorsi, and injury can weaken resisted adduction and extension. It also supports flap planning. Use this plate in gross anatomy and kinesiology courses when students are asked to trace attachments from the spine and pelvis to the humerus and predict actions at the shoulder. It also fits well in orthopedic and plastic surgery teaching files discussing latissimus dorsi tendon transfer and the latissimus dorsi myocutaneous flap for breast or chest wall reconstruction. Anatomical accuracy verified by SciePro's Medical Advisory Board.