Carpal tunnel syndrome:
The carpal tunnel is the space between the bones and ligaments of the wrist through which median nerve passes. Carpal tunnel syndrome develops when the nerve becomes compressed. It is common condition of the hand that affects women more frequently than men.
The symptoms of carpal tunnel syndrome include:
- Pins and needles or tingling sensations (Paraesthesias)
- Pain or numbness in the hand, typically worse at the night.
- Clumsiness and weakness of the hand.
- A weak grip and an impaired ability to bring the thumb across the palm to meet the other fingers.
- Pain in the wrist,forearm or shoulder.
Any condition that narrows the carpal tunnel or produces swelling of or fluid retention by the contents of the tunnel can cause carpal tunnel syndrome. The many possible causes include
- Hormonal changes.
- Diabetes mellitus,
- Rheumatoid arthritis,
- Acromegaly – bone enlargement due to pituitary gland abnormality.
- Under activity ofthyroid (hypothyroidism)
- Renal failure,
- Amyloidosis : rare condition in which abnormal proteins accumulate in tissues and organs.
- Paget’s disease: a chronic bone disease that affects elderly people. The bones become deformed and thickened.
- Tumors: such as lipoma (Fatty tumours), ganglions (fluid filled cysts formed in tendon), and deformities of wrist after the fractures.
- The use of hand held vibrating tools – very rarely causes carpal tunnel syndrome.
The typical history of pain and weakness in the hands usually suggest the diagnosis of carpal tunnel syndrome, but it is important to exclude other conditions that may produce similar symptoms, such as a prolapsed cervical disc or arthritis of thumb joint.
This may reveal disturbances in sensation in the area supplied by the median nerve,wasting of the muscles at the base of thumb and poor grip.
- Tinel’s sign: tapping the median nerve at the wrist may reproduce the pain and tingling of carpal tunnel syndrome in the affected person. Flexing the wrist against resistance has a similar effect.
- Imaging:an x-ray of the wrist may be used to rule out bony abnormalities, while MRI gives a clear picture of the soft tissues.
- Nerve conduction studies: Nerve conduction studies are conducted to see the conduction and velocity of impulses across the median nerve. This test can be used for documentation of carpal tunnel syndrome.
Treat the underlying cause:
The underlying causes should be treated. For example overweight patients should be encouraged to lose some weight and patients with hypothyroidism should receive thyroid hormone replacement therapy.
Some patients recover without treatment, while others respond to rest or simple measures such as the use of wrist splint for week or so. In cases where the condition is persistent however several treatments are available.
- Anti-inflammatory drugs: may help to relive tendon swelling and pressure on the wrist in rheumatoid arthritis.
- Wearing night splints at night, which hold the wrist, slightly forward, may help night pain.
- Diuretics (which increase the volume of urine) are sometimes prescribed to remove excess fluid from the body.
- Steroid injections into the carpal may provide relief, but must be performed with utmost care. It is particularly important not to inject the median nerve itself any improvement may be temporary.
- In persistent cases,surgery will be performed in order to reduce pressure on the large media nerve.
Surgery is usually advisable for persistent or worsening symptoms to prevent permanent loss of sensation and wasting of the muscles in the hand. In such cases without surgery, symptoms are likely to persist.
Surgical treatment usually involves dividing transverse carpal ligament in order to relieve the pressure on the median nerve. Freeing the nerve enables normal nerve conduction to resume.Traditionally, median nerve decompression was open surgical procedure, but also new technique of endoscopic carpal tunnel release is also being practiced.
Generally, both open and endoscopic techniques have excellent results although it may take few months for grip strength to return to normal.