Hawaii Massage License Practice Exam

Into what bone does the deltoid muscle insert?

1. Radius

2. Scapula

3. Humerus

4. Clavicle

The correct answer is: Humerus

The deltoid muscle inserts into the humerus, specifically at the deltoid tuberosity, which is located mid-way down the bone. This muscle is crucial for the abduction of the arm, particularly when the arm is raised away from the body. The deltoid is named for its triangular shape, resembling the Greek letter delta, and it covers the shoulder joint, playing a pivotal role in various arm movements. Understanding the anatomy of the deltoid and its connection to the humerus is fundamental for comprehending upper limb mechanics, especially in activities that involve lifting or rotating the arm. The other options pertain to different bones that are either not directly related to the deltoid's function or location, underscoring the importance of precise anatomical knowledge in massage therapy and related fields.