The forearm has two bones: the radius and the ulna. In order to determine which forearm bone is medial to the body, we need to remember standard anatomical position. In this position, the palms face outward, meaning the pinky is the closest finger to the body. The ulna is on the side of the pinky, while the radius is on the side of the thumb. As a result, the ulna is the forearm bone medial to the body.

The humerus is located proximal to the radius and ulna and forms the shoulder joint with the scapula. The clavicle is superior to the humerus and articulates with the scapula above the shoulder.

The humerus articulates with the scapula, making the glenohumeral joint at the head, and the radius and ulna, making the elbow joint at the trochlea. The anatomic neck is the area immediately below the head that functions as attachment for the joint capsule of the glenohumeral joint. The spiral groove houses the radial nerve and serves as an attachment site for the lateral and medial head of the biceps brachii.

The surgical neck is located between the anatomical neck and shaft of the humerus, marking a narrower region of the bone. The surgical neck is the most common site of fracture on the humerus. The axillary nerve and the posterior humeral circumflex artery also course through this region and can be damaged in the case of injury.

The carpal bones are found arranged in two layers of four in the hand. The first row, lateral to medial, is made of the scaphoid, lunate, triquetrum, and pisiform. The distal row, from lateral to medial, is made of the trapezium, trapezoid, capitate, and hamate. A fracture of the scaphoid during a fall on an outstretched hand can damage the radial artery. A fracture of the hamate can cause damage to the ulnar nerve and artery.

The carpal bones articulate with the radius bone in the forearm to create the wrist; the ulna has no contact with the carpal bones in the hand.  

The coronoid process is a structure on the proximal ulna, not to be confused with the coracoid on the scapula or the conoid on the clavicle. The coronoid process forms part of the trochlear notch on the ulna.

When the ulna is extended, the olecranon, which is an extension of the ulna, fits into the olecranon fossa of the humerus. 

The supraspinatus is responsible for initiating abduction of the arm for the first 15 degrees, while the deltoid continues the abduction. 

There are only four muscles that comprise the rotator cuff. All of the answer choices except the teres major are rotator cuff muscles.

The wrist contains 8 carpal bones. The scaphoid, lunate, triquetrum, and pisiform make up the proximal row, while the trapezium, trapezoid, capitate, and hamate make up the distal row. A mnemonic to help you remember these eight bones is: Some Lovers Try Positions That They Can't Handle. In the anatomical position, from lateroproximal to mediodistal: Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, Hamate.

The olecranon is a feature of the ulna. It is commonly known as the elbow. The coracoid process can be found on the scapula and both the deltoid tuberosity and trochlea can be found on the humerus.

The coracoid process is a projection on the scapula that serves as an attachment site for ligaments which help to stabilize the shoulder. It is located proximally to the articulation of the humerus and scapula. The head of the humerus is smooth and round to fit into the glenoid cavity of the scapula. It has no sites for attachment. The humerus is the long bone of the upper arm. It is the head of the humerus that interacts with the ligaments attaching to the coracoid process. The clavicle, also known as the collar bone, articulates with another projection from the scapula called the acromion. It is posterior to the coracoid process.