The scapula or shoulder blade is a flat, triangular-shaped bone that to the posterior surface of ribs 2-7.
Scapula Bone Anatomy
Markings of the Scapula Bone:
- It has three borders (superior, lateral, medial), three angles (superior, lateral, medial) and two surfaces (costal, dorsal). A prominent ridge or spine divides the dorsal surface into two, unequal parts called the supraspinous fossa and infraspinous fossa.
- A shallow depression at the lateral angle called the glenoid cavity the head of the humerus to form the shoulder or gleno-humeral joint.
- The muscles that originate on the scapula (extrinsic muscles) insert on the humerus, radius, and ulna. They cause the humerus to rotate, abduct, adduct, flex or extend.
