Which three anatomical landmarks are used to palpate the deltoid muscle belly?

The deltoid muscle is a prominent muscle located on the shoulder, and understanding its anatomy is crucial for effective palpation and treatment. The correct landmarks for palpating the deltoid muscle belly are the acromion, the lateral one-third of the clavicle, and the deltoid tuberosity.

The acromion is the bony process on the scapula that forms the highest point of the shoulder and serves as an important reference point for the deltoid's origin. The lateral one-third of the clavicle is significant because it marks the site where the anterior fibers of the deltoid muscle start. Lastly, the deltoid tuberosity is the insertion point on the humerus where the muscle attaches. This structure is easily palpated along the lateral side of the humerus.

These three anatomical landmarks create a triangulated area that outlines the muscle's belly, allowing for precise identification and effective manipulation during massage or therapeutic interventions. Understanding these landmarks also aids in differentiating between muscle fibers and adjacent structures for improved assessment and treatment outcomes.