Flexor Pollicis Brevis

Description

Schematic drawings of the right hand, palmar view, with the thenar muscles shown in two layers Only bony attachments are shown. Left) Overview of the thenar muscles as visible after skinning the hand. Both heads of the flexor pollicis brevis are covered by the abductor pollicis. Right) Abductor pollicis and opponens pollicis are completely removed. The deep head of Cruveilhier (orange; a.k.a. the deep head of the flexor pollicis brevis) is shown with two heads attaching onto the ulnar and radial side at the base of the proximal phalanx of the thumb. The superficial head of the flexor pollicis brevis (dark orange) has a single head that inserts ulnarward onto the proximal phalanx of the thumb.

Alternative Names

• FPB
• Flexor Pollicis Brevis Muscle
• Short Flexor Muscle of the Thumb
• Short Flexor of the Thumb
• Musculus Flexor Pollicis Brevis
• Thenar Flexor Muscle
• Thenar Thumb Flexor
• Superficial Thenar Flexor Muscle
• Deep Thenar Flexor Muscle
• Thumb Flexor Muscle

General

• Flexor of the thumb
• Part of the thenar eminence

Origin

• Superficial head: flexor retinaculum
• Deep head: capitate and trapezium

Insertion

• Base of proximal phalanx of 1st finger

Actions

• Flexion of carpometacarpal joint, metacarpophalangeal joint of 1st digit

Artery

• Superficial palmar branch of radial artery

Nerve

• Recurrent branch of median nerve

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Clinical Significance

• Carpal Tunnel Syndrome
• Median Nerve Injury
• Trigger Finger

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See Also

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

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