Carpal Tunnel Syndrome (CTS)

Carpal Tunnel Syndrome is a common condition that can cause pain, tingling, numbness, and weakness in the hand and arm.

The median nerve is a major nerve that runs down your arm, and passes through the Carpal Tunnel in your wrist before supplying your hand and fingers. Flexor tendons and the Median nerve pass through the tunnel; synovium lubricates the tendons and allows easy movement of the fingers.

Repetitive flexion and extension in the wrist significantly increases the fluid pressure in the tunnel through thickening of the synovial tissue that lines the tendons within the carpal tunnel. Swelling of the synovium ultimately puts pressure on the Median nerve resulting in pain, numbness, tingling, and weakness in the hand.

What are the causes of Carpal Tunnel Syndrome?

The causes of carpal tunnel syndrome are mostly unknown, but some common risk factors include- repetitive wrist work, arthritis, obesity, hormonal changes during pregnancy, diabetes, trauma.

Certain extrinsic factors that are likely to exert pressure from outside the tunnel and cause Carpal Tunnel Syndrome are- benign tumors or lipomas, improperly formed blood vessels, etc.

What are the symptoms of Carpal Tunnel Syndrome?

Some common symptoms:

• Numbness, tingling or pain especially on the thumb side of the hand. Shaking your hand may give you temporary relief
• The pain may radiate upwards toward the shoulder
• Loss of strength in the thumb or hand
• Feeling of loss of coordination. You may experience clumsiness in doing up your buttons, handling coins or using chopsticks.
• Pain may be exacerbated at night or sleep due to wrist posture. The pain may even wake you from sleep.
• In severe cases, you may notice shrinking of the muscles at the base of your thumb. This is called Thenar Atrophy or wasting.

Do I need to see a Doctor? Can I leave it alone?

Carpal Tunnel Syndrome has varying degrees of severity.

Carpal tunnel syndrome, for most people, gradually worsens over time without some form of treatment. It is important to be evaluated and diagnosed early on to slow or stop the progression of the disease.

What tests will I need?

Your doctor will take a thorough history and conduct a physical examination. This is usually enough to clinch the diagnosis of Carpal Tunnel Syndrome.

Nerve conduction study is routinely done to confirm the diagnosis of CTS. Electrodiagnostic studies can provide baseline data and exclude other pathology that presents with similar symptoms. It also aids to ascertain the severity of the disease.

Ultrasound is an increasingly popular investigation in evaluating a diagnosis of CTS, especially if a patient cannot tolerate nerve conduction testing. It diagnoses CTS based on the following measurements: median nerve cross-sectional area, median nerve flattening ratio and palmar displacement of the flexor retinaculum.

Your doctor may also order an MRI to make sure there are no co-existing more proximal sites of nerve compression. Nerves may also be compressed at your neck, the thoracic outlet, or other sites in your arm such as the Pronator tunnel.

What treatment options are there?

If your symptoms are mild, your surgeon will usually recommend a course of non-surgical methods to start with.

Non-surgical methods

Splints/Braces

Splints or braces can be used, especially at night, to keep the wrist from bending. A rigid splint can keep the wrist in a neutral position, and reduce the symptoms that are caused by falling asleep with the wrist in an awkward position.

Corticosteroids

Corticosteroid is a powerful anti-inflammatory agent that can be injected into the carpal tunnel to temporarily calm the symptoms. The use of ultrasound while performing the injection leads to faster resolution of CTS symptoms. The injections are done under local anesthesia.

Median nerve gliding exercises

1. Begin with your wrist in a neutral position, fingers and thumb bent into a fist, with your thumb facing you.

2. Extend your fingers and thumb into a straight, neutral position.

3. Keeping your fingers and thumb straight, bend your wrist so that your palm faces up. 

4. Keeping your hand in the same position, extend your thumb away from your hand. 

5.  Keeping your hand and fingers in the same position, rotate your wrist so that your palm faces away from you.

6. While in position 5, gently pull down on your thumb with your free hand.

Hold each position for five seconds, repeat series three to five times.

Surgical methods

Surgery is recommended when there is constant numbness and muscle weakness despite non-surgical treatment. Surgery is also recommended when the Carpal Tunnel Syndrome is severe enough that the Median Nerve damage is causing denervation and atrophy (shrinking) of the hand muscles. In the case of atrophy , delay is not recommended as the weakness may be permanent.

The surgical procedure performed for carpal tunnel syndrome is called a “carpal tunnel release.” There are two different surgical techniques for doing this, but the goal of both is to relieve pressure on the median nerve by cutting the transverse carpal ligament that forms the roof of the tunnel. This increases the size of the tunnel and decreases pressure on the median nerve.

Open carpal tunnel release (OCTR) is currently the gold standard surgical procedure for treatment of this condition and is associated with a high success rate of up to 90% in many studies. It is a very safe operation that can be performed under local or regional anaesthesia (Bier’s block). 

Endoscopic carpal tunnel release (ECTR) is an alternative to OCTR. In ECTR, an endoscope and cutting instrument is inserted via a small incision at the level of wrist crease and the carpal ligament is divided under direct vision. This technique has gained in popularity over the years due to the perceived benefits of smaller scar, better post-operative comfort as well as less wound pain.

If you suspect you have carpal tunnel syndrome, see your doctor. If left untreated, the condition can disrupt your daily life. But effective treatments for carpal tunnel syndrome are available.