Which point is at the origin of the deltoid muscle?

• A. SJ 13
• B. SJ 15
• C. SJ 12
• D. SJ 14

Answer: (D)

The main idea here is understanding where the deltoid muscle begins. The deltoid originates from the lateral third of the clavicle, the acromion, and the spine of the scapula, and it fans out to insert on the humerus. The point SJ14 (Jianliao) is located in the hollow on the shoulder directly over the origin area of the deltoid, near the acromial region. That placement lines up with where the deltoid muscle starts to rise from the bone, so SJ14 is the point that corresponds to the origin of the deltoid. The other shoulder points are situated in different parts of the shoulder region (posterior scapular area or along the chest/upper back) and do not sit at the deltoid’s origin, so they’re not the correct match.