Anatomy of Mammary Glands

Arm Muscles and Nerves

• The main flexor muscle of the arm is not specified.
• The nerve responsible for flexion of the forearm is not specified, but damage to it would affect forearm flexion.

Blood Supply

• The brachial artery has a terminal branch that supplies blood to the arm.
• The lateral thoracic artery primarily supplies blood to the lateral part of the mammary gland.

Breast Anatomy

• The pectoralis major muscle is attached to the coracoid process of the scapula.
• The median nerve is located in the upper half of the arm, near the breast.
• The brachial artery is located in the lower half of the arm, near the breast.
• The breast receives lymphatic drainage from the deep surfaces, which goes to the subclavicular lymph nodes.
• The sensory function of the breast is innervated by the fourth, fifth, and sixth intercostal nerves.
• The subclavicular lymph nodes receive drainage from the breast, but not the popliteal lymph nodes.
• Cooper's ligaments provide support to the mammary gland.
• The right lymphatic duct drains lymph from the right side of the body, including the right breast.

Shoulder Joint

• The anterior and posterior blood supply to the shoulder joint comes from the anterior and posterior circumflex humeral arteries.
• The subscapularis muscle is primarily responsible for medial rotation of the shoulder joint.
• The axillary nerve is most commonly injured during a shoulder dislocation.
• The teres minor muscle is part of the rotator cuff, but the pectoralis major muscle is not.
• The suprascapular artery is primarily responsible for the blood supply to the shoulder joint.
• The deltoid muscle is primarily responsible for abduction of the shoulder joint.
• The most common type of anterior shoulder dislocation is the subcoracoid type.
• The mammary glands do not have a function of producing testosterone.

Muscle Functions

• The pectoralis major muscle is responsible for flexion of the shoulder joint.
• The pectoralis major muscle has a clavicular head that originates from the clavicle and a sternal head that originates from the sternum and costal cartilages of ribs 3-5.
• The pectoralis major muscle pulls the scapula antero-inferiorly.
• The latissimus dorsi muscle has a different function than the pectoralis major muscle.
• The pectoralis major muscle has a primary function of adduction, extension, and medial rotation of the humerus.