Carpal Tunnel Syndrome: Causes, Diagnosis and Treatment

Carpal tunnel syndrome can result from any condition that causes pressure over the median nerve as it passes through the carpal tunnel.

Before reading further it would be good to first see Wrist Anatomy (skip if you have already done so).

• five times more common in women
• usually between the age of 40 to 60 years
• dominant limb is more commonly involved

Disease and conditions that can cause carpal tunnel syndrome include

• displaced fracture of the distal part of Radius bone
• inflammation from infections, Rheumatoid Arthritis and Gout
• tumors such as Xanthoma or Ganglion of wrist
• use of vibrating machinery
• Diabetes Mellitus and Obesity
• Amyloidosis
• typists who work for long hours
• pregnancy

Symptoms are produced by inflammation and pressure on the median nerve. They include

• abnormal sensations are present in the palm, thumb, middle and index fingers
• pain, numbness and burning sensation (occur after several hours of sleep and cause the patient to wake up)
• exercising, rubbing or shaking the hand may produce relief from pain
• flexion of the wrist can produce a increase in the symptoms (Phalen test)
• pressure on the front of the wrist can also cause a increase in abnormal sensation (Tinel test)

Investigations required to confirm the diagnosis include

• X ray of the wrist to see for any malunited fracture or bony growth.
• Nerve conduction studies are done. A slowing of the speed and delay in the ability to pick up the sensation is seen in the median nerve. These studies are 90% accurate.
• Ultrasound of the nerve can show an increase in the thickness of the nerve indicating the presence of inflammation.
• MRI scan of the wrist can show good images of the bones and other tissues. Swelling and nerve compression can be visualized. This test is seldom required.

Treatment of carpal tunnel syndrome includes

• no treatment is required during pregnancy as the syndrome resolves spontaneously after pregnancy
• splinting of the wrist in neutral position (neither extended nor flexed)
• use of NSAIDs (drugs such as aspirin, diclofenac and ibuprofen)
• injection of steroid into the carpal tunnel
• multivitamin supplements
• if there is no response to the above treatment methods then surgical release of the transverse carpal ligament is done.

Surgical release of the transverse carpal ligament can be done by two methods

• Open method
• Endoscopic method

In the open method the ligament is cut by making a incision on the skin of the palm just beyond the wrist crease. The ligament is cut under direct vision.

In the endoscopic method a small cut is made in the skin. Now a small telescope is inserted to visualize the ligament on a monitor. The ligament is then cut with a special blade.

I prefer the open method as I am more familiar with it. The open method also insures that the ligament is cut completely, where as incomplete cutting of the ligament has been seen with the endoscopic method.

The green coloured flexor retinaculum (transverse carpal ligament) in this graphic is cut during surgery.

Frequently Asked Questions

When can I expect cure with non-operative treatment?

Cure with non-operative treatment can be expected when

• age is less than 50 years
• symptoms have been present for less than 10 months
• abnormal sensations are occasionally present

How successful is surgical treatment?

Surgical treatment has a 90% success rate. Poor results usually occur due to a wrong diagnosis. Personally I think that the use of MRI can eliminate the poor results of surgery by confirming the diagnosis

Can I have recurrence after surgery for Carpal tunnel syndrome?

Yes recurrence can occur and re operation may be required. Recurrence usually occurs due to the continuation of the disease process in the carpal tunnel and not due to any lapse during surgery.

I hope the information provided was helpful. If you have any query you can ask me at the contact me page.

This page was last updated on 5th January 2011.