Carpal tunnel syndrome

Background

• Most common focal mononeuropathy
• Results from compression of median nerve at wrist where it traverses the carpal tunnel
• Median nerve provides sensation to the palmar aspect digits 1-3 and radial side of 4th
• Etiology:
  • Repetitive wrist flexion/extension, DM, amyloidosis, trauma, edema

Clinical Features

History

• Pain, paresthesia, and numbness in distribution of median nerve
  • Palmar aspect of thumb, index, middle, and radial aspect of ring finger
• Awakening at night w/ burning pain and tingling in hand

Physical

• Tinel sign
  • Tapping on palmar aspect of wrist reuslts in electric shock sensation shooting into hand
  • SN 0.50 and SP 0.77
• Phalen maneuver
  • Holding wrists in flexion for 60 seconds evokes or worsens symptoms
  • SN 0.68 and SP 0.73
• Durkan sign
  • Manual compression of carpal tunnel reproduces symptoms after 30 seconds
  • SN 0.64 and SP 0.83
  • More sensitive and specific than Tinel and Phalen in earlier studies

Differential Diagnosis

• Proximal Lesion
  • Spinal cord lesion
  • Cervical redicular pain
  • Thoracic outlet syndrome
  • Multiple Sclerosis (MS)
• Systemic condition
  • Raynaud syndrome
  • Pregnancy (Main)
  • B12 deficiency
  • Diabetic neuropathy
  • Hypothyroidism
  • Hypocalcemia
• Ulna neuropathy

Treatment

1. Behavioral modification
2. Wrist splint w/ wrist in neutral position
3. NSAIDs (although not clearly effective)
4. Diuretics (if edema is significant contributor to pt's symptoms)

Source

Tintinalli