3 – Anatomy: The clavipectoral fascia
The clavipectoral fascia (synonym: costocoracoid membrane or coracoclavicular fascia) extends from the clavicle superiorly, medially it is fused with the fascia covering the medial end of the upper intercostal spaces, laterally it is attached to the coracoid process and the fascia over the short head of the biceps brachia muscle; caudally it is fused with the axillary fascia
It creates a fascial space behind the clavicular part of the major pectoral muscle containing the branches of the pectoral nerves and the pectoral branch of the thoracoacromial artery
It splits in two layers that enclose the subclavius and minor pectoral muscles
The portion extending from the first rib to the coracoid process is often stronger than the rest and is known as the costocoracoid ligament
The costocoracoid ligament is pierced by the cephalic vein and the thoracoacromial artery and vein, together with the lateral pectoral nerve (see picture on the left)