Carpal tunnel syndrome

The carpal tunnel is a narrow passage at the base of the hand that contains tendons, ligaments, bones and the median nerve. When it narrows, nerve compression occurs and can cause pain, numbness and tingling. It is the most common compressive neuropathy, affecting up to 10% of the population.

In most cases there is no single identified cause that leads to the syndrome, but factors that may increase the risk of occurrence have been identified:

• Anatomical alterations, produced by injuries to the wrist, such as fractures or dislocations. In addition, people who have a smaller carpal tunnel have a higher rate of involvement.
• It is more frequent in women because they naturally have a narrower carpal tunnel.
• Certain diseases. Conditions that cause nerve damage, such as diabetes, or those with an inflammatory component, such as rheumatoid arthritis, can affect the proper functioning of the median nerve.
• Obesity.
• Fluid retention, which can increase pressure within the carpal tunnel.
• Work environment. Work with vibrating tools or those requiring repetitive wrist movements can increase damaging pressure on the median nerve.

Symptoms usually begin progressively and manifest as warmth, cramping or numbness of the palm of the hand and fingers, especially the thumb and index finger. As the condition worsens, the symptoms become more pronounced and may even lead to dropping objects due to weakness or numbness.

The sensation can extend from the wrist to the arm and is often more pronounced at night, while driving or holding something for a long period of time, such as a book. Many patients find that moving or shaking the hands helps in relieving the symptoms.

There is no proven way to prevent the syndrome, but you can reduce the risk by minimizing the strain on hands and wrists with these methods:

• If the job poses some risk, try to reduce force and grip.
• Take periodic breaks by gently stretching and flexing the hands and wrists. Whenever possible, alternate tasks.
• Maintain a relaxed position by avoiding excessive bending of the wrist. If working at a computer, keep the keyboard at elbow level.
• Keep hands at a warm temperature as heat increases pain and stiffness.