Deep Posterior Compartment of the Forearm

Description

Deep dorsal compartment

Deep muscles of the dorsal (posterior) forearm including abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, extensor indicis, supinator.

Alternative Names

• Deep posterior forearm compartment
• Deep extensor compartment of the forearm
• Deep dorsal forearm compartment
• Posterior forearm (deep layer)
• Deep extensor layer of the forearm

General

• Contains five muscles
• With the exception of supinator, these muscles act on the thumb and index finger
• Deep compartment of the Posterior Compartment of the Forearm

Muscles

• Abductor Pollicis Longus
• Extensor Pollicis Brevis
• Extensor Pollicis Longus
• Extensor Indicis
• Supinator

Primary Functions

• Thumb abduction and extension
• Index finger extension
• Forearm supination (via supinator)
• Fine motor control of wrist and digits

Innervation

• Posterior Interosseous Nerve (terminal branch of the Radial Nerve)
• Pure motor innervation (no cutaneous sensory function)

Blood Supply

• Posterior Interosseous Artery (branch of the ulnar artery via common interosseous artery)

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Clinical Significance

• Forearm Pain Main
• Acute Compartment Syndrome
• Posterior Interosseous Nerve Syndrome
• Radial Tunnel Syndrome

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See Also

• Forearm Pain Main
• Forearm Anatomy Main
• Physical Exam Wrist

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