Carpal Tunnel Syndrom


Carpal tunnel syndrome (CTS)

CTS is the most common entrapment neuropathy. CTS is median nerve injury due to compression, traction or friction at the level of wrist. The syndrome is characterized by pain, paresthesia, numbness and weakness in the median nerve distribution of the hand. CTS has an enormous economic impact due to the costs associated with lost working hours, reduced earnings, restricted work activities. Early diagnosis and timely treatment of CTS can prevent irreversible nerve damage and permanent disability. 


Causes of CTS
Predisposition factors include diabetes mellitus, hypothyroidism, renal disease, alcoholism, rheumatoid arthritis, obesity, pregnancy, and menopause. Compression could be due to intrinsic or extrinsic factors. Fracture, dislocation, space occupying lesions (tumors, cysts) can lead to entrapment of median nerve. Congenitally small carpal tunnel may predispose to nerve compression. Chronic nerve compression can be caused by pressure against hard surface. Use of vibrating hand held tools, highly repetitive forceful motion of upper extremity and abnormal hand position can lead to CTS. 

There are several high risk occupations for CTS. People in occupation that require repetitive or forceful hand movement or sustained exertion of the upper limb are at risk for CTS. These include carpenters, butchers, grinders, factory workers, garment workers, packers, cashiers, elevator operators, computer operators, dentists, pneumatic tool operators and drilling machine operators. Athletes and sportsperson may be at risk due to direct injury or repetitive trauma due to throwing and catching. 

Clinical manifestations
There are paresthesias (abnormal sensation, tingling) in the hand induced by activity. They may occur typically at night (few hours after retiring) and are relieved by shaking or massaging the hand. These may radiate to the wrist, elbow, forearm or shoulder. Patients complain that the hand feels fat, swollen, weak, clumsy and objects drop from the hand. 

A typical history, physical examination with positive Phalens' and Tinel's sign is diagnostic. Electrodiagnostic studies - nerve conduction studies of median nerve demonstrate delayed conduction across the carpal tunnel on the affected side. 

Lunate is usually subluxated in this case. Chriopractric adjustment may be enough to put lunate in its proper location. Medical conservative treatment depends on the cause and severity of the condition. Wrist splinting and changing habits may be sufficient in mild CTS. Moderate CTS may require medications. Local steroid and lignocaine may bring temporary relief. 

Surgical treatment by decompression of the median nerve by release of the transverse carpal ligament is indicated in severe CTS not responding to medical treatment.