Carpal Tunnel Syndrome

Description

Carpal tunnel syndrome (CTS) is a condition that causes pain, numbness and tingling (paresthesia) in the hand and arm as a result of increased pressure on the median nerve, one of major nerves in the wrist and hand. In patients with CTS, the tunnel becomes narrowed or the tissues surrounding the flexor tendons (synovium) swells causing the median nerve to be compressed or squeezed as it passes through the wrist. The purpose of the synovium is to lubricate the tendons, allowing them to easily move. When the synovium swells, the space within the carpal tunnel is reduced, causing crowding around the nerve. Due to the compression, the nerve does not function properly. Early diagnosis and treatment are key as the majority of cases worsen over time.Symptoms: In the majority of CTS cases, symptoms develop gradually and without a specific injury. Patients with CTS may notice that their symptoms come and go, however, as the condition worsens, symptoms may occur more frequently or may persist for longer periods of time.

Symptoms

In the majority of CTS cases, symptoms develop gradually and without a specific injury. Patients with CTS may notice that their symptoms come and go, however, as the condition worsens, symptoms may occur more frequently or may persist for longer periods of time. 

Common symptoms include

• Numbness
• Tingling
• Burning
• Pain in the wrist and hand
  • Symptoms are noted primarily in the thumb, index, middle, and ring fingers, but may travel through the wrist and up the forearm.
• Hand weakness: Weakness can cause difficulty with fine movements such as buttoning your clothes or may cause you to drop things.
• Increase in symptoms when holding something for extended period of time: Activities with the wrist bent forward or backward, such as talking on the phone, texting, reading a book or driving may cause your symptoms to flare up.
• Inability to sleep through the night: Many people sleep with their wrists bent which can cause an increase in symptoms and may awaken you from your sleep.
• In severe cases, there may be visible decrease in the size the thumb and hand muscles (atrophy).

Causes

• Swelling of tissue around the flexor tendons
• Narrowing of the tunnel

Risk Factors

• Heredity: A smaller or abnormally shaped carpal tunnel may change the amount of space available for the nerve. These traits often run in families.
• Repetitive hand use: Repetitive hand and wrist motions or activities over a prolonged period of time, such as typing or writing, may aggravate the tendons in the wrist, causing swelling that puts pressure on the nerve. 
• Hand and wrist position: Doing activities that involve extreme flexion or extension of the hand and wrist for a prolonged period of time can increase pressure on the nerve.
• Pregnancy: Hormonal changes during pregnancy can cause swelling, potentially reducing the space within the carpal tunnel.
• Health conditions: Diabetes, rheumatoid arthritis, and thyroid gland imbalance are conditions that are associated with carpal tunnel syndrome

Prevention

• Avoid repetitive hand movements
• Avoid prolonged hand use

 Diagnosis:

Early diagnosis and treatment are key as the majority of cases worsen over time. A doctor will discuss your symptoms, review your medical history, and perform a thorough physical examination of your hand.

• Electrophysiological tests: Electrophysiological tests may be performed to determine how well your median nerve is working as well as identify any additional nerve conditions that may be contributing to your symptoms. Electrophysiological tests may include:
  • Nerve conduction studies to measure nerve signals and detect when a nerve is not conducting effectively. These studies can help your doctor guide your treatment plan by determining how severe your problem is. 
  • Electromyogram (EMG) to measure the electrical activity in muscles and identify any nerve or muscle damage.
• Ultrasound:  An ultrasound of your wrist may be recommended to evaluate the median nerve for signs of compression created by the surrounding bone and tissue.
• X-rays: X-rays may be performed to exclude other causes for your symptoms, such as a fracture, ligament injury or arthritis.
• Magnetic resonance imaging (MRI) scans: A MRI may be performed to determine if there are any problems with the nerve, such as a tumor or scarring from an injury. It will also help identify any abnormal tissues that may be impacting the nerve or other causes for your symptoms.

Treatment

There are non-surgical and surgical treatment options. Treatment for moderate or mild cases typically begins conservatively. However, if a patient presents with a severe case or symptoms persist despite conservative treatment methods, surgery is often recommended to avoid irreversible nerve damage from occurring.