What is carpal tunnel syndrome?
Carpal tunnel syndrome (CTS) is a neurological disease, which occurs due to entrapment of median nerve at the level of wrist. "Carpus" is a Greek word, which means "wrist". CTS is a common disease (affecting about 5% of population) and commonly affects women in their middle age.
What are the main symptoms of CTS?
1. Pain in the affected hand is the commonest symptom. Pain mainly occurs in the fingers (all fingers may be affected except the little finger), hand, forearm or the arm. It is often more at night, and interferes with activities of daily living.
2. Tingling (pins and needles sensations) and burning sensations may occur in the affected hand, which again are often more at night.
3. Numbness (inability to feel touch or pain sensations) of the hand may occur.
4. Weakness of the fingers and hand on the affected side may occur, which can be accompanied by thinning of muscles at the base of thumb (thenar muscles).
Are there some job/lifestyle related factors that predispose a person to develop CTS?
Any job or condition, where an excess pressure is applied at the level of wrist (front aspect) may predispose an individual to develop CTS. Some of these conditions include:
1. Computer use: While using a computer (mouse or keyboard), the wrist commonly rests on the surface and the median nerve at the level of wrist gets constantly pressed at the level. Therefore, people who mainly work at computers (such as software professionals, etc) have a higher risk of developing CTS.
2. Driving: Holding a steering while driving also puts a lot of pressure over the wrist, predisposing to CTS.
3. Playing musical instruments: Median nerve at the wrist may get compressed by playing instruments like tabla, drums, etc; resulting in CTS.
4. Sitting (for long duration) and resting the hand on the table with wrist touching the table surface can also press the median nerve resulting in CTS.
What are the common diseases/conditions which result in CTS?
1. Rheumatoid arthritis- a condition where there is joint pain and swelling affecting several joints. If the wrist joint is affected, median nerve may get compressed.
2. Hypothyroidism- CTS may occur in patients with thyroid hormone deficiency.
3. Pregnancy- Water retention and swelling of hands and feet are common during pregnancy, which predisposes to CTS.
4. Trauma/fracture at the level of wrist
How is the diagnosis of CTS made?
1. You need to consult a Neurologist, who will examine you. Examination would include assessment of wrist joint & its mobility, tests of sensation (touch, pain, etc) in the hand & fingers, and assessment of strength in fingers and hand. Tinel's sign (tingling and pain in the hand/fingers, which is brought on by tapping at the level of wrist) may be positive.
2. NCV (nerve conduction velocity studies) are ordered by the neurologist to assess the function of the median nerve. An impulse travels slowly across the entrapped median nerve, which can be assessed by the NCV. EMG (electromyography) may also be done to see the affected muscles at the base of thumb (which are supplied by the median nerve).
3. Ultrasound examination at the level of wrist (carpal tunnel) may actually demonstrate the compressed median nerve and the factors responsible for it. In a recent case, I could identify a small benign tumor compressing on the median nerve, causing CTS.
4. Blood tests may be done to look for thyroid disease and rheumatoid arthritis.
How is CTS treated?
1. Resting the wrist and avoiding excessive flexion or extension at the wrist joint. Braces or splints may be applied at the wrist to maintain it in neutral position, which may be applied only during the night or both day and night.
2. Analgesics- such as paracetamol/etoricoxib may be useful in mild cases.
3. Neuropathic pain medications- such as gabapentin, pregabalin or duloxetine are useful in about 50% of cases.
4. Local steroid injections at the level of wrist are useful in some. This is a safe procedure and can be done in outpatient/office as a day care procedure.
5. Surgery is reserved for cases not responding to the above measures (1-4). It is referred to as carpal tunnel decompression surgery. In this surgery, surgeon makes a cut at the level of the wrist and frees the median nerve from any pressure-causing structures. Surgery is safe, can be done under local anaesthesia as a daycare procedure.
6. Physiotherapy is useful in most cases.
What is the prognosis (outcome) in CTS?
CTS has an excellent prognosis, if it is properly treated. Early diagnosis and treatment is vital to a good outcome. If left untreated, in addition to causing severe pain, it can lead to permanent numbness of fingers & hands and weakness of hand/fingers.
If you have any queries, please email me at firstname.lastname@example.org
Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Health City, Hyderabad, India