Latissimus dorsi insertion is which of the following?

Latissimus dorsi insertion is which of the following?

• A. Medial border of scapula
• B. Floor of intertubercular groove of humerus
• C. Lateral lip of intertubercular groove
• D. Infraglenoid tubercle

Answer: (B)

Latissimus dorsi inserts into the floor of the intertubercular (bicipital) groove of the humerus. Its tendon winds from the back, around the teres major, and attaches at the bottom of that groove between the tubercles. This placement lets the muscle pull the arm downward and backward (extension, adduction, and medial rotation). The other options point to different structures: the medial border of the scapula is where rhomboids insert, the lateral lip of the intertubercular groove is the insertion of pectoralis major, and the infraglenoid tubercle is the origin for the long head of the triceps.

Latissimus dorsi inserts into the floor of the intertubercular (bicipital) groove of the humerus. Its tendon winds from the back, around the teres major, and attaches at the bottom of that groove between the tubercles. This placement lets the muscle pull the arm downward and backward (extension, adduction, and medial rotation). The other options point to different structures: the medial border of the scapula is where rhomboids insert, the lateral lip of the intertubercular groove is the insertion of pectoralis major, and the infraglenoid tubercle is the origin for the long head of the triceps.