Corpus: Forearm

The forearm's skeleton comprises two bones: the radius and the ulna. These are connected by key ligaments, notably the radial collateral annular ligament and the interosseous membrane of the forearm.

The forearm's musculature includes flexor muscles on the palmar side, extensor muscles on the dorsal side, and radial muscles. These muscles facilitate movements at the elbow joint, wrist, and fingers.

Radialis musculature

• brachioradialis muscle
• extensor carpi radialis brevis muscle
• extensor carpi radialis longus muscle

Superficial extensors

• extensor carpi ulnaris muscle
• extensor digitorum muscle
• extensor digiti minimi muscle

Deep extensors

• abductor pollicis longus muscle
• extensor pollicis brevis muscle
• extensor pollicis longus muscle
• extensor indicis proprius muscle
• supinator muscle

Superficial flexors

• flexor carpi radialis muscle
• flexor carpi ulnaris muscle
• flexor digitorum superficialis muscle
• palmaris longus muscle
• pronator teres muscle

Deep flexors

• pronator quadratus muscle
• flexor pollicis longus muscle
• flexor digitorum profundus muscle

The forearm primarily receives blood from the brachial artery, which originates in the upper arm and bifurcates at the elbow's bend into two branches, the radial and ulnar arteries.

The forearm muscles are mainly innervated by fibers of the radial, median, and ulnar nerves originating from the brachial plexus.

The forearm can flex or extend at the elbow joint. The hand can also rotate approximately 180° through pronation and supination, involving movement of the radius and ulna.