What upper arm muscle is named for its shape often the site of injections that abducts and rotates is?

Deltoid

The deltoid muscle is a thick, triangular-shaped muscle

located on the front, side and back of the shoulder. It is made

up of three parts: the anterior deltoid, the lateral deltoid, and the posterior deltoid.

Functions

- Abduction (moving the arm away from the body)

- Flexion (bending the arm at the elbow)

- Extension (straightening the arm at the elbow)

- External Rotation (turning the arm away from the body)

- Internal rotation (turning the arm toward the body)

The deltoid muscle is innervated by the axillary nerve.

Clinical Significance

- The deltoid muscle is often the site of injections, such as vaccines and blood draws

- Injuries to the deltoid muscle can occur from trauma, overuse, or shoulder instability