The deltoid muscle, located on the outside of the shoulder, helps rotate the upper arm and extend the arm at the shoulder. The deltoid has three different sets of fibers that help perform specific tasks. More »

The deltoid tuberosity is the oblong vertical section of the lateral surface on the mid-humeral shaft, notes anatomyExpert. This area is the attached part of the deltoid muscle. More » Science Human Anatomy

Deltoid muscles, situated in the shoulders, are responsible for the majority of arm movements, including arm abduction, arm flexion and medial rotation, and arm extension and lateral rotation. These movements involve the... More »

Inner Body says that the three parts of the deltoid muscle are the anterior fibers, lateral fibers and posterior fibers. Each band of fibers originates from a separate location. More » Science Human Anatomy Muscles

Intramuscular injections are given primarily in three locations: the vastus lateralis muscle found in the thigh, the deltoid muscle found in the shoulder and the ventrogluteal or dorsogluteal muscles found in the buttock... More »

According to MedlinePlus, deltoid muscle atrophy is a condition in which the deltoid muscles of the shoulder have become wasted or diminished, resulting in loss of strength or movement. Causes of deltoid muscle atrophy i... More »

The rotator cuff is a group of muscles and tendons that connects the shoulder blade to the upper arm. It is composed of four muscles and various tendons that surround the shoulder socket. More » Science Human Anatomy Muscles