Carpal Tunnel Syndrome
- Is an entrapment syndrome resulting from compression of the median nerve in the tendon sheath within the ventral surface of the wrist.
- Similarly, tarsal tunnel syndrome is a group of symptoms caused by pressure on the posterior tibial nerve in the medial aspect of the ankle and cubital tunnel syndrome is caused by pressure on the ulnar nerve at the medial epicondyle of the elbow.
- Compression symptoms due to entrapment include paresthesias, numbness, pain, weakness, and muscle atrophy.
- Compression results from repetitive motion of the wrist, trauma, local tenosynovitis, and mass, such as ganglion or neuroma.
- Repetitive motion causing carpal tunnel include the use of computer, typing, and use of a jackhammer.
- Carpal tunnel syndrome is more common in those over age 50, in women, in pregnant women in the first trimester, and in those with rheumatoid arthritis.
- Complications include chronic pain and loss of function of the extremities.
- Progressive sensory changes including paresthesias and numbness of the thumb, index finger, and ring finger of the involved hand; leads to pain waking the patient up at night.
- Motor changes beginning with clumsiness and progressing to weakness; edema and thenar atrophy may be noted.
- Positive Tinel’s sign: Increased paresthesias on tapping of tendon sheath (ventral surface of central wrist).
- Positive Phalen test: Increased symptoms with acute palmar flexion for 1 minute.
- Electromyogram shows weakened response to median nerve stimulation.
Therapeutic and Pharmacologic Interventions:
- Wrist splint in slight extension (cock-up splint) to relieve pressure aggravated by wrist flexion: worn at night, and during day if symptomatic.
- Avoidance of flexion and twisting motion of the wrist.
- Work or activity modification to relieve repetitive strain.
- Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen 600 to 800 mg tid to relieve inflammation and pain.
- Corticosteroid injection into tendon sheath to relieve inflammation.
- Surgery is indicated when conservative measures fail to relieve symptoms.
- Procedure is release of carpal ligament and tendon to relieve pressure on median nerve.
- Monitor level of pain, numbness, paresthesias, and functioning.
- Monitor for adverse effects of NSAID therapy, especially in elderly. GI distress or bleeding, dizziness, or increased serum creatinine.
- After surgery, monitor neurovascular status of affected extremity: pulses, color, swelling, movement, sensation, or warmth.
- Apply wrist splint so wrist is in neutral position, with slight extension of wrist and slight abduction of thumb; make sure that it fits correctly without constriction.
- Administer NSAIDs and assist with tendon sheath injections as required.
- Apply ice or cold compress to relieve inflammation and pain.
- Teach patient the cause of condition and ways to alter activity to prevent flexion of wrists; refer to an occupational therapist as indicated.
- Advise patient of NSAID therapy dosage schedule and potential adverse effects; instruct patient to report GI pain and bleeding.
- Teach patient to gentle range-of-motion exercises; refer to a physical therapist as indicated.