Cs 2.1 Ch 9.1

The axillary artery is a continuation of the subclavian branch of the aortic arch. This means that it is a direct extension of the subclavian artery, which originates from the aortic arch. The axillary artery begins at the outer border of the first rib and extends to the lower border of the teres major muscle. It supplies blood to the upper limb, including the shoulder, arm, and some chest muscles.

The humeroradial joint is formed by the articulation of the capitulum of the humerus and the radial head. This joint allows for flexion and extension of the forearm. The trochlea of the humerus articulates with the ulna to form the humeroulnar joint. The radial notch of the ulna articulates with the head of the radius to form the proximal radioulnar joint. The coronoid process of the ulna articulates with the coronoid fossa of the humerus to form the humeroulnar joint. Therefore, the correct answer is that the capitulum and radial head articulate to form the humeroradial joint.

The correct answer is Median. In the cubital fossa, the median nerve runs just medial to the brachial artery. The median nerve is responsible for providing motor and sensory innervation to the muscles of the anterior forearm and the palm of the hand. It also plays a role in wrist and finger flexion, as well as thumb opposition.

The biceps brachii, long-head tendon merges with the shoulder labrum at the superior aspect. This means that the long-head tendon of the biceps brachii muscle attaches to the superior part of the shoulder labrum.

The fat pads in the elbow function similarly to bursae in other synovial joints. Bursae are fluid-filled sacs that reduce friction and provide cushioning between bones, tendons, and muscles. Similarly, the fat pads in the elbow act as shock absorbers and provide cushioning between the bones and soft tissues. They help to protect the joint and facilitate smooth movement.

The transverse humeral ligament serves to protect the tendon of the biceps brachii, long-head muscle. It is a flat band of connective tissue that extends across the intertubercular groove of the humerus, holding the tendon in place and preventing it from dislocating or moving out of position during arm movements. The other ligaments listed in the options do not specifically protect the tendon of the biceps brachii, long-head muscle.

The surgical neck of the humerus is named due to its susceptibility to fracture. This portion of the bone is located just below the tubercles and is a common site for fractures, particularly in older individuals. Fractures in the surgical neck can occur as a result of trauma or repetitive stress on the bone. The name "surgical neck" reflects the fact that this area is frequently involved in surgical interventions to repair fractures or other injuries.

The pectoralis minor muscle inserts on the coracoid process of the scapula. This muscle is located in the anterior shoulder region and is responsible for stabilizing and depressing the scapula. It originates from the third, fourth, and fifth ribs and attaches to the coracoid process. Its main function is to assist in pulling the scapula forward and downward, aiding in movements such as protraction and depression of the shoulder joint.

The deltoid muscle is not part of the rotator cuff. The rotator cuff is a group of muscles and tendons that surround the shoulder joint and help to stabilize and move the shoulder. The supraspinatus, teres minor, and subscapularis are all muscles that make up the rotator cuff. The deltoid muscle, on the other hand, is a large muscle that covers the shoulder and is responsible for lifting the arm away from the body.

The humeroulnar joint of the elbow is formed by the trochlea of the humerus and the trochlear notch of the ulna. These two structures articulate together to allow for flexion and extension of the forearm. The trochlea is a spool-shaped structure on the distal end of the humerus, while the trochlear notch is a corresponding concave surface on the proximal end of the ulna. This articulation allows for the hinge-like movement of the elbow joint.

The ulnar collateral ligament is the correct answer because it is the elbow ligament that has three bands. The ulnar collateral ligament is located on the inner side of the elbow and consists of an anterior, posterior, and transverse band. These bands provide stability to the joint and help prevent excessive side-to-side movement.

The ulnar nerve is not located in the cubital fossa. The cubital fossa is a triangular depression on the anterior aspect of the elbow, and it contains the median nerve, the brachial artery, and the biceps tendon. The ulnar nerve, on the other hand, runs posterior to the medial epicondyle of the humerus and does not pass through the cubital fossa.

The raised prominence on the dorsal aspect of the scapula is called the scapular spine. The scapular spine is a bony ridge that runs diagonally across the scapula, providing attachment for various muscles and ligaments. It serves as an important landmark for anatomical reference and is easily palpable on the surface of the back. The coracoid process is a separate bony projection on the scapula, located on the anterior aspect. The glenoid process is a shallow socket on the lateral aspect of the scapula, forming part of the shoulder joint. The inferior angle refers to the lowermost point of the scapula.

The brachial plexus is the correct answer because it is responsible for innervating the shoulder structures. The brachial plexus is a network of nerves that originates from the lower cervical and upper thoracic spinal nerves. It gives rise to several nerves that supply the muscles and skin of the shoulder, arm, and hand. The other options, such as the cervical plexus, axillary plexus, and cephalic plexus, do not specifically innervate the shoulder structures.

The latissimus dorsi is the correct answer because it is a large muscle that originates from several locations, including the posterior aspect of the iliac crest. This muscle plays a significant role in shoulder movement and stability, as well as in actions such as pulling and reaching. The teres major, trapezius, and rhomboid major muscles do not have origins on the posterior aspect of the iliac crest.