Anatomical Snuffbox

Vocabulary flashcards covering the anatomy, boundaries, contents, and clinical significance of the anatomical snuffbox.

Anatomical Snuffbox

A triangular, superficial skin depression located on the lateral (radial) aspect of the back of the hand at the base of the thumb, which becomes visible when the thumb is fully extended.

Lateral (Radial) Border

The border of the anatomical snuffbox formed by two parallel-running tendons of the outcropping muscles of the forearm: the Abductor pollicis longus (APL) and Extensor pollicis brevis (EPB).

Medial (Ulnar) Border

The border of the anatomical snuffbox formed by the solitary tendon of the Extensor pollicis longus (EPL).

Proximal Border

The border of the anatomical snuffbox formed by the styloid process of the radius.

Distal Border (Apex)

The border of the anatomical snuffbox that points toward the first metacarpophalangeal (MCP) joint.

Roof of the Anatomical Snuffbox

The superficial structure covering the anatomical snuffbox, formed by the skin and superficial fascia.

Floor of the Anatomical Snuffbox

The deep base composed of the Scaphoid bone (proximally), Trapezium bone (distally), the base of the first metacarpal bone, and the tendons of the extensor carpi radialis longus and extensor carpi radialis brevis.

Radial Artery

The most lateral arterial vessel in the wrist that travels across the carpal bones on the floor of the snuffbox, where a pulse can be palpated by pressing against the scaphoid bone.

Superficial Branch of the Radial Nerve

A completely sensory nerve in the hand that runs over the roof of the anatomical snuffbox to provide feeling to the skin on the back of the first 3.5 fingers and the thumb base.

Cephalic Vein

A vein arising from the dorsal venous network of the hand that crosses the anatomical snuffbox as it travels up the side of the forearm.

Scaphoid Fracture

A fracture of the most frequently injured carpal bone, usually caused by a fall onto an outstretched hand; indicated by tenderness inside the snuffbox and carrying a risk of avascular necrosis and permanent wrist arthritis due to poor retrograde blood supply.

De Quervain’s Tenosynovitis

A painful inflammation affecting the first dorsal compartment tendons (APL and EPB) that form the lateral border of the anatomical snuffbox.