Forearm

Styloid Process of Ulna

Styloid Process of Ulna The structure indicated is the styloid process of the ulna. The styloid process of the ulna is a bony process that extends from the distal end of the ulna bone. Attaching to the styloid process of the ulna is the ulnar collateral ligament of the wrist. Learn more about the anatomy of the radius and ulna in this tutorial
Styloid process of ulna

Extensor Carpi Ulnaris

Extensor Carpi Ulnaris The structure indicated is the extensor carpi ulnaris muscle of the forearm. The extensor carpi ulnaris muscle is one of 7 muscles located in the superficial compartment of the posterior forearm. The posterior forearm consists of a superficial and a deep compartment. The superficial compartment contains 7 muscles, whereas the deep compartment contains 5 muscles. The superficial compartment of the posterior forearm includes the following 7 muscles: Brachioradialis Extensor carpi radialis longus Extensor carpi radialis brevis Extensor digitorum Extensor digiti minimi Extensor carpi ulnaris Anconeus The muscles of the posterior compartment of the forearm originate from the …

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extensor carpi ulnaris

Cephalic Vein

Cephalic Vein The structure indicated is the cephalic vein. The cephalic and basilic veins are the main superficial veins of the upper limb. The cephalic vein originates from the dorsal venous network of the hand and drains into the axillary vein by passing through the deltoid and pectoralis major muscles. In the cubital fossa, which is the area located anterior to the elbow joint, the cephalic vein is joined to the basilic vein via the median cubital vein. In the clinical setting, the median cubital vein is a convenient and common location for obtaining venous access for the administration of …

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cephalic vein

Abductor Pollicis Longus

Abductor Pollicis Longus The structure indicated is the abductor pollicis longus muscle of the posterior forearm. The abductor pollicis longus muscle is one of the muscles located in the deep layer of muscles in the posterior compartment of the forearm. There are 5 muscles in the deep layer of the posterior forearm: Supinator Abductor pollicis longus Extensor pollicis brevis Extensor pollicis longus Extensor indicis The abductor pollicis longus muscle, as the name suggests abducts the thumb. Origin: Posterior surface of proximal ulna, radius and interosseous membrane Insertion: Base of 1st metacarpal Innervation: Posterior interosseous nerve Action: Abduction and extension of …

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abductor pollicis longus

Anconeus

Anconeus The structure indicated is the anconeus muscle of the forearm. The anconeus muscle is one of the muscles of the posterior compartment of the forearm. The posterior compartment consists of a superficial layer of muscles comprised of 7 muscles. The deep layer is comprised of 5 muscles. Origin: lateral epicondyle of humerus Insertion: olecranon, proximal surface of ulna Innervation: Radial nerve Action: assists elbow extension, stabilises the elbow joint, abducts ulna during pronation Learn about the muscles of the forearm in this tutorial.
anconeus

Brachioradialis

Brachioradialis The structure indicated is the brachioradialis muscle of the forearm. The brachioradalis muscle is one of the muscles of the posterior compartment of the forearm. The posterior compartment consists of a superficial layer of muscles comprised of 7 muscles. The deep layer is comprised of 5 muscles. Origin: lateral supracondylar ridge of humerus Insertion: radial styloid process Innervation: radial nerve Action: flexes the forearm at the elbow – strongest when forearm is midway between pronation and supination. Learn more about the muscles of the forearm in this tutorial.
brachioradialis

Pronator Teres

Pronator Teres The structure indicated is the pronator teres muscle. The pronator teres is one of four muscles in the superficial layer of muscles in the anterior compartment of the forearm. The anterior compartment of the forearm consists of three layers of muscles: Superficial layer Intermediate layer Deep layer Four muscles are located in the superficial layer (from lateral to medial): Flexor carpi ulnaris Palmaris longus Flexor carpi radialis Pronator teres All four muscles of the superficial layer have a common origin on the medial epicondyle of the humerus. Origin:  humeral head – medial epicondyle of humerus; ulnar head – …

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Pronator Teres