Carpal tunnel syndrome is a median nerve entrapment neuropathy caused by compression of the median nerve in the carpal tunnel.

Causes

• Idiopathic
• Pregnancy
• Obesity
• Rheumatoid arthritis
• Local extrinsic pressure, e.g. ganglion, lipoma, fracture, haematoma
• Endocrinological
  • Diabetes
  • Hypothyroidism
  • Acromegaly

Clinical features

• Intermittent paraesthesia, pain/burning and numbness of thumb, first, middle and radial half of ring finger
• Loss of strength and wasting of the thenar eminence
• Symptoms often worse at night
• Phalen’s test +ve
• Tinel’s test +ve

Management

• Conservative
  • Watch and wait (spontaneous resolution occurs in 25% over 1 year)
  • Wrist splint (especially at night)
  • Corticosteroid injection
  • NSAIDs may help
• Surgical carpal tunnel release: transverse carpal ligament over volar aspect of wrist incised under local anaesthesia) – recurrence rare

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