The scapula, also known as the shoulder blade, is a flat, triangular bone located on the upper back. It connects the humerus (upper arm bone) with the clavicle (collarbone). Here are the main parts of the scapula:
- Spine of the Scapula: A prominent ridge that runs diagonally across the posterior surface of the scapula.
- Acromion: The lateral extension of the spine of the scapula, which forms the highest point of the shoulder and articulates with the clavicle.
- Glenoid Cavity: A shallow socket that articulates with the head of the humerus, forming the shoulder joint.
- Coracoid Process: A hook-like projection on the anterior surface of the scapula, which serves as an attachment point for muscles and ligaments.
- Supraspinous Fossa: The area above the spine of the scapula, which provides attachment for the supraspinatus muscle.
- Infraspinous Fossa: The area below the spine of the scapula, which provides attachment for the infraspinatus muscle.
- Subscapular Fossa: The large, concave area on the anterior surface of the scapula, which provides attachment for the subscapularis muscle.
- Superior Angle: The uppermost angle of the scapula, located near the base of the neck.
- Inferior Angle: The lowermost angle of the scapula, which moves as the arm is raised or lowered.
- Lateral Border: The outer edge of the scapula, which runs from the glenoid cavity to the inferior angle.
- Medial Border: The inner edge of the scapula, which runs parallel to the spine.
Understanding these parts is essential for studying the anatomy and function of the shoulder joint.