Extrinsic Muscles of the Thumb

Description

(a) Posterior extrinsic muscles of the thumb; (b) Intrinsic muscles of the thumb. Also known as thenar muscles

Anatomical snuff box (III). Note the scaphoid bone, the wrist joint proximal to the scaphoid, and the midcarpal joint distal to it.

Name

• Long (extrinsic) muscles of the thumb
• Extrinsic Muscles of the Thumb

General

• Extrinsic muscles of the thumb act on the thumb but originate in the forearm

Muscles

• Flexor Pollicis Longus
• Extensor Pollicis Longus
• Extensor Pollicis Brevis
• Abductor Pollicis Longus

Anatomic Relationships

• Contribute to formation of Anatomic Snuffbox
• Ulnar/medial: Tendon of the extensor pollicis longus
• Radial/lateral: Tendons of the extensor pollicis brevis, abductor pollicis longus

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Clinical Significance

• Needs to be updated

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See Also

• Wrist Pain Main
• Hand And Wrist Anatomy
• Physical Exam Wrist

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