Carpal tunnel syndrome
QT Pathologies (EN)
There is a space in the wrist called the carpal tunnel where the median nerve and nine tendons pass from the forearm into the hand.
Carpal tunnel syndrome (CTS) happens when pressure builds up from swelling in this tunnel and puts pressure on the nerve.
When the pressure from the swelling becomes great enough to disturb the way the nerve works, numbness, tingling, and pain may be felt in the hand, fingers and in the arm.
It is a nerve compression due to a mismatch between the container (carpal tunnel) and content (the median nerve and tendons).
- Anatomy of the carpal tunnel : median nerve passing beneath the flexor retinaculum (= roof of the tunnel) Anatomy images courtesy and copyright of Primal Pictures Ltd – www.primalpictures.com
CTS commonly affects women in middle age but can occur at any age in either sex. Pressure on the nerve can happen several ways :
- Swelling of the lining of the flexor tendons, called tenosynovitis
- Joint dislocations and fractures
- Arthritis and congenital abnormalities
- Keeping the wrist bent for long periods of time
- Overuse of the wrist and fingers in repetitive flexion, extension, gripping, pushing or pulling
- Fluid retention during pregnancy
- Thyroid conditions, rheumatoid arthritis, diabetes and amyloidosisTumor and abnormal muscle belly
There may be a combination of causes.
Carpal tunnel syndrome symptoms usually include pain, numbness, tingling (paresthesias), or a combination of the three.
The numbness or tingling most often takes place in the thumb, index, middle, and ring fingers.
The symptoms usually are increased during the night and awaken the patient who has to shake their hands to try to releave the symptoms.
Symptoms also may be noticed during daily activities such as driving or reading a newspaper.
Patients may sometimes notice a weaker grip, occasional clumsiness (buttoning clothes or picking up objects), and a tendency to drop things. The patient has the feeling of swollen hands.
In severe cases, sensation may be permanently lost and the muscles at the base of the thumb slowly shrink (thenar atrophy), causing difficulty with pinch.
A detailed history including medical conditions, how the hands have been used, and whether there were any prior injuries is important.
The clinical examination will reveal several positive signs for a CTS.
X-rays are sometimes required to check for the other causes of the complaints such as arthritis or a fracture. A specific X-ray of the carpal tunnel (Hart and Gaynor incidence) may be taken to analyse the tunnel geometry.
In some cases, laboratory tests may be done if there is a suspected medical condition that is associated with CTS.
Electrodiagnostic studies (NCV–nerve conduction velocities and EMG–electromyogram) may be done to confirm the diagnosis of carpal tunnel syndrome as well as to check for other possible nerve problems.
- Hart and Gaynor radiological incidence
Symptoms may often be relieved without surgery. Identifying and treating medical conditions, changing the patterns of hand use, or keeping the wrist splinted in a straight position may help reduce pressure on the nerve.
Wearing wrist splints at night may relieve the symptoms that interfere with sleep. A steroid injection into the carpal tunnel may help relieve the symptoms by reducing swelling around the nerve.
When symptoms are severe or do not improve, surgery may be needed to make more room for the nerve.
Pressure on the nerve is decreased by cutting the ligament that forms the roof (top) of the tunnel on the palm side of the hand. Incisions for this surgery may vary, but the goal is the same: to enlarge the tunnel and decrease pressure on the nerve.
Following surgery, soreness around the incision may last for several weeks or months. The numbness and tingling may disappear quickly or slowly.
It may take several months for strength in the hand and wrist to return to normal.
Carpal tunnel symptoms may not completely go away after surgery, especially in severe cases.
During your consultation, Dr. D'Agostino will discuss the current treatment options and can help you choose the best treatment based on your particular case.