Carpal Tunnel Syndrome

CARPAL TUNNEL SYNDROME Most common nerve entrapment disorder. Prevalence: 2.7%, twice as many women as men Etiology: heredity, size of the carpal tunnel, associated local and systemic diseases, and habits Associated conditions: • • • • • • • • •

Idiopathic - 43 % Colles' fracture or other wrist trauma — 13.4 percent Rheumatoid arthritis and other inflammatory rheumatic disease — 6.5 percent Menopause — 6.4 percent Diabetes — 6.1 percent Osteoarthritis of the wrist — 5.3 percent Pregnancy — 4.6 percent (and 7.0 percent in women between the ages of 15 and 44) most often made during the final trimester and resolves with delivery Myxedema — 1.4 percent Other medical disorders (eg, acromegaly, amyloidosis, hepatic disease, fibromyalgia, benign local tumors, ) — 7.3 percent

Acute wrist flexion during resting positions when sleeping, reading, or driving Cumulative trauma related to certain jobs, hand transmitted vibration exposure Diagnostic criteria: by National Institute of Occupational Safety and Health •

One or more of the following symptoms affecting at least part of the median nerve distribution of the hand: paresthesias; hypesthesia; pain; or numbness

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One or more of the following objective findings: physical findings of median nerve compression including a positive Hoffman-Tinel sign or a positive Phalen test (acute wrist flexion maintained for 30 to 60 seconds reproduces symptoms.); diminished or absent sensation to pin prick in the median nerve distribution; or electrodiagnostic findings indicative of median nerve dysfunction across the carpal tunnel.

The sensitivity and specificity of the Hoffman-Tinel test were 0.60 and 0.67; sensitivity and specificity of the Phalen maneuver were 0.75 and 0.47 Katz hand diagram: a self–administered diagram, which depicts both the dorsal and palmar aspect of the patient's hands and arms; 80% and the specificity is 90% for the diagnosis of CTS

Long-term involvement leads to thenar muscle atrophy with associated loss of thumb abduction and opposition strength

Electrodiagnostic testing (using nerve conduction velocity (NCS) without electromyography) of carpal tunnel syndrome can be used for both diagnosis and localization of the entrapment. Somewhat painful, expensive, and is recommended in patients who have not responded to conservative therapy, in those whose diagnosis is unclear after history and physical examination, and in patients with evidence of motor dysfunction or thenar atrophy. Sensitivities between 49% and 84% and specificities of 95% and 99% Management Splinting the wrist at a neutral angle helps to decrease repetitive flexion and rotation, thereby relieving mild soft tissue swelling or tenosynovitis; most effective when it is applied within three months of the onset of symptoms NSAIDs, diuretics, and pyridoxine are no more effective than placebo in relieving the symptoms of carpal tunnel syndrome. Orally administered corticosteroids: prednisolone dosage of 20 mg per day for two weeks, followed by 10 mg per day for two weeks Combined injection of a corticosteroid and a local anesthetic into or proximal to the carpal tunnel can be used in patients with mild to moderate carpal tunnel syndrome Ultrasonic therapy Carpal tunnel release surgery should be considered in patients with symptoms that do not respond to conservative measures and in patients with severe nerve entrapment as evidenced by nerve conduction studies, thenar atrophy, or motor weakness.