Final answer:
The spine of the scapula is a distinct ridge on the backside of the scapula, which can be felt through the skin. It is part of the scapula's structure, providing attachment points for shoulder and arm muscles.
Step-by-step explanation:
The spine of the scapula refers to a prominent ridge located on the posterior aspect of the scapula, which can be palpated behind the shoulder. The scapula is a flat, triangular bone that plays a crucial role in the shoulder joint's function. It provides a broad area of attachment for muscles, acting as a support structure for movements of the shoulder and arm. Additionally, the scapula features prominent projections like the coracoid process and the acromion, which serve as attachment sites for various muscles and form joints such as the acromioclavicular joint with the clavicle. Muscles that move the shoulder and arm attach to these bony protrusions, enabling ranged movements and support.