Guyons Canal

Description

Canal of Guyon. Arrows indicate section levels. The roof of the canal has been removed and elevated on the ulnar side

Illustration of the Guyon's canal overlying an MRI of the wrist

Name

• Guyon’s Canal
• Ulnar Tunnel
• Ulnar Canal
• Canal of Guyon

Etymology

• First described by French urologist Jean Casimir Felix Guyon (1831-1920)

General

• Fibro-osseous tunnel along the anterior wrist
• Transmits the ulnar neurovascular bundle from the forearm into the hand
• Superficial, slightly proximal to transverse carpal ligament of the carpal tunnel
• Approximately 4 cm in length, spans from proximal pisiform to hook of hamate

Boundaries

• Medial/ulnar aspect: pisiform, flexor carpi ulnaris tendon, abductor digiti minimi
• Lateral/radial aspect: hook of hamate
• Superficial/roof: palmar carpal ligament
• Deep/floor: flexor retinaculum, pisohamate ligament, hypothenar muscles

Contents

• Ulnar Nerve
  • Bifurcation within the canal
  • Superficial channel: superficial/ulnar branch, ulnar artery
  • Second channel: deep/ radial branch of the ulnar nerve
• Ulnar Artery and ulnar vein
• Veins associated with the ulnar nerve
• Fat, lymphatic vessels

Anatomic Variants

• Abductor digiti mini ocassionally has an anomalous presence in Guyons canal
• Present in 25% of one study population and can cause compression, leading to Guyon canal syndrome

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Clinical Significance

• Guyon Canal Syndrome

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See Also

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

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