Which muscle shares the same insertion point on the humerus as latissimus dorsi?

Which muscle shares the same insertion point on the humerus as latissimus dorsi?

• A. Teres major
• B. Deltoid
• C. Pectoralis major
• D. Infraspinatus

Answer: (A)

Latissimus dorsi attaches to the intertubercular groove (bicipital groove) of the humerus, and teres major also inserts there, specifically at the medial lip of that groove. That shared insertion point is why teres major is the correct answer. This arrangement lets them work together to adduct and internally rotate the arm, and to extend it from a flexed position. The other muscles attach to different landmarks: deltoid at the deltoid tuberosity, pectoralis major at the lateral lip of the groove, and infraspinatus at the greater tubercle, so they don’t share the exact insertion site.

Latissimus dorsi attaches to the intertubercular groove (bicipital groove) of the humerus, and teres major also inserts there, specifically at the medial lip of that groove. That shared insertion point is why teres major is the correct answer. This arrangement lets them work together to adduct and internally rotate the arm, and to extend it from a flexed position. The other muscles attach to different landmarks: deltoid at the deltoid tuberosity, pectoralis major at the lateral lip of the groove, and infraspinatus at the greater tubercle, so they don’t share the exact insertion site.