The carpal tunnel is a narrow passageway in the wrist, which opens into the hand. It is enclosed by the bones of the wrist (underneath) and the transverse carpal ligament (across the top).
Many structures pass through the carpal tunnel, including:
The median nerve, which gives feeling to the thumb, forefinger, middle finger and half of the ring finger. The muscles of the thumb are also innervated by the median nerve. A person with advanced carpal tunnel syndrome may find weakness in thumb movements and difficulty grasping objects.
Many tendons also pass through the carpal tunnel – the long flexor tendons from the forearm run through the carpal tunnel into the hand. These tendons are covered by a smooth membrane called the tenosynovium and allow hand movement.
Signs and symptoms
The symptoms of carpal tunnel syndrome include:
- Pins and needles
- Pain, particularly at night
- Darting pains from the wrist
- Radiated or referred pain into the arm and shoulder
- Weakness of the hand
- The little finger and half of the ring finger are unaffected.
Any risk factor that causes a reduction in the amount of space inside the carpal tunnel can cause carpal tunnel syndrome. If left unchecked, the median nerve is squashed against the transverse carpal ligament until the nerve cannot function properly. Numbness and pain are the result. It can affect one or both hands. Many factors can increase your risk of developing carpal tunnel syndrome. These include:
- Anatomic factors: A wrist fracture or dislocation that alters the space within the carpal tunnel can create pressure on the median nerve. Carpal tunnel syndrome is generally more common in women. This may be because the carpal tunnel area is relatively smaller than in men and there’s less room for error. Women who have carpal tunnel syndrome may also have smaller carpal tunnels than women who don’t have the condition.
- Nerve-damaging conditions: Some chronic illnesses, such as diabetes and alcoholism, increase your risk of nerve damage, including damage to your median nerve.
- Inflammatory conditions: Illnesses that are characterized by inflammation, such as rheumatoid arthritis or an infection, can affect the tendons in your wrist, exerting pressure on your median nerve.
- Alterations in the balance of body fluids: Certain conditions — such as pregnancy, menopause, obesity, thyroid disorders and kidney failure, among others — can affect the level of fluids in your body. Fluid retention may increase the pressure within your carpal tunnel, irritating the median nerve. Carpal tunnel syndrome associated with pregnancy generally resolves on its own after the pregnancy is over.
- Workplace factors: It’s possible that working with vibrating tools or on an assembly line that requires prolonged or repetitive flexing of the wrist may create harmful pressure on the median nerve, or worsen existing nerve damage. There is little evidence to support extensive computer use as a risk factor for carpal tunnel syndrome, although it may cause a different form of hand pain.
Early diagnosis and treatment are important to avoid permanent damage to the median nerve. An Osteopath will perform a physical examination of the hands, arms, shoulders, and neck which can help determine if your complaints are related to daily activities or to an underlying disorder, and can rule out other painful conditions that mimic carpal tunnel syndrome. The wrist is examined for tenderness, swelling, warmth, and discoloration. Each finger is tested for sensation, and the muscles at the base of the hand are examined for strength and signs of muscle wasting.
Occasionally it is necessary to confirm the diagnosis by use of electrodiagnostic tests:
- Nerve conduction study: electrodes are placed on the hand and wrist to measure the speed with which nerves transmit impulses.
- Electromyography: electrical activity can be viewed on a screen to determine the severity of damage to the median nerve.
- Ultrasound imaging: may show impaired movement of the median nerve.
Initial treatment of carpal tunnel syndrome generally involved resting the affected hand and wrist for at least two weeks – avoiding all activities that might aggravate the symptoms. If there is inflammation, applying a cool pack can help to reduce swelling.
Osteopathic management consists of ensuring optimal hand, wrist, elbow, shoulder and neck biomechanics with techniques such as joint articulations, manipulations, and soft tissue therapies. Identifying and removing the aggravating or underlying causative factor is important for a long term resolution.
Stretching and strengthening exercises are often helpful once the severity of the initial symptoms have reduced. Yoga has also been shown to reduce pain and improve grip strength among some patients with carpal tunnel syndrome.
Medication: Nonsteroidal anti-inflammatory drugs, such as aspirin, ibuprofen, and other on-prescription pain relievers, may ease symptoms that have been present for a short time or have been caused by strenuous activity. Orally administered diuretics may help to decrease swelling. Corticosteroids* can be injected directly into the wrist or taken by mouth to relieve pressure on the median nerve and provide immediate, temporary relief to persons with mild or intermittent symptoms. Additionally, some studies show that vitamin B6 (pyridoxine) supplements may ease the symptoms of carpal tunnel syndrome.
*Corticosterioids should not be taken without a doctor’s prescription.
Occasionally carpal tunnel symptoms do not resolve with conservative treatment alone. Carpal tunnel release is one of the most common surgical procedures and is generally considered if symptoms last for 6 months. Surgery involves severing the band of tissue across the wrist (transverse carpal ligament) to reduce pressure on the median nerve.
Although symptoms may be relieved immediately after surgery, full recovery from carpal tunnel surgery can take months. Some patients may have infection, nerve damage, stiffness, and pain at the scar. Occasionally the wrist loses strength because the carpal ligament is cut. After surgery, an Osteopath will assist to restore wrist strength and mobility.
Recurrence of carpal tunnel syndrome following treatment is rare. The majority of patients recover completely.
If you are suffering from any type of hand or wrist pain, contact us for an appointment.