Upper limb
Pectoralis Major, Clavicular Head
Musculus pectoralis major (pars clavicularis)
- Origin
- Medial half of the clavicle
- Insertion
- Crest of the greater tubercle of the humerus, together with the other heads
- Function
- Flexion and horizontal adduction of the arm at the glenohumeral joint
- Innervation
- Lateral pectoral nerve, C5-C6
- Movement & chain
- The most cranial fibers of the pectoralis major; work together with the anterior deltoid to bring the arm forward and across the chest.
- Palpation
- Palpable immediately inferior to the medial clavicle during resisted arm forward flexion and horizontal adduction.
- Clinical
- Specifically tested to isolate the lateral pectoral nerve (C5–C6); preserved in isolated lower sternocostal pectoralis tears.
- Segmental innervation
- Myotome C5-C6.
- In clinical practice
- Wound management post-laparotomy/chest drain and abdominal wall monitoring; support incision site during coughing to prevent wound dehiscence.
- Region in the model
- Upper limb