Overview:
Carpal tunnel syndrome (CTS) is a common condition that causes pain, numbness, and tingling in the hand and arm. It occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes compressed or squeezed at the wrist. The carpal tunnel, a narrow passageway in the wrist formed by bones and ligaments, houses the median nerve and flexor tendons responsible for finger movement.
Anatomy:
The carpal tunnel consists of the carpal bones on the bottom and sides and the transverse carpal ligament on top. Within this tunnel, the median nerve and nine flexor tendons pass through, facilitating finger movement and providing sensation to the palm and fingers.
Causes:
Carpal tunnel syndrome is often caused by a combination of factors that increase pressure on the median nerve or reduce the space within the carpal tunnel. Contributing factors may include:
- Repetitive Hand Use: Activities that involve repetitive wrist movements, such as typing, assembly line work, or using vibrating tools, can lead to inflammation and swelling of the tendons, compressing the median nerve.
- Hand and Wrist Positioning: Prolonged or awkward positioning of the wrist, such as flexion or extension, can aggravate the median nerve and increase pressure within the carpal tunnel.
- Anatomical Factors: Certain anatomical variations, such as a smaller carpal tunnel size or cysts or tumours within the tunnel, can predispose individuals to carpal tunnel syndrome.
- Medical Conditions: Underlying medical conditions such as diabetes, rheumatoid arthritis, hypothyroidism, or pregnancy can increase the risk of developing carpal tunnel syndrome due to their association with nerve compression or fluid retention.
- Trauma or Injury: Previous wrist fractures, dislocations, or traumatic injuries can lead to structural abnormalities or scar tissue formation within the carpal tunnel, impinging on the median nerve.
Symptoms:
The hallmark symptoms of carpal tunnel syndrome include:
- Pain and Tingling: Individuals may experience pain, burning, or tingling sensations in the thumb, index finger, middle finger, and half of the ring finger. These symptoms may radiate up the arm or worsen at night.
- Numbness: Numbness or loss of sensation may occur in the fingers or palm, leading to a feeling of clumsiness or weakness in the hand.
- Weakness: Weakness or decreased grip strength may develop, making it challenging to perform fine motor tasks or hold objects.
- Wrist Discomfort: Some individuals may experience discomfort or aching in the wrist or forearm, particularly with repetitive hand movements or wrist flexion.
Diagnosis:
Diagnosis of carpal tunnel syndrome involves a comprehensive evaluation of symptoms, medical history, and physical examination. Your healthcare provider may perform specific tests such as:
- Tinel’s Sign: Tapping over the median nerve at the wrist to elicit tingling or electric shock-like sensations in the fingers.
- Phalen’s Maneuver: Holding the wrists in flexion for 60 seconds to reproduce symptoms.
- Nerve Conduction Studies: Electromyography (EMG) and nerve conduction studies (NCS) may be conducted to assess nerve function and identify areas of compression along the median nerve pathway.
- Imaging Studies: X-rays, ultrasound, or MRI may be ordered to rule out other causes of wrist pain or evaluate structural abnormalities within the carpal tunnel.
Treatment:
Treatment for carpal tunnel syndrome aims to relieve symptoms, reduce inflammation, and improve nerve function:
- Wrist Immobilisation: Wearing a splint or brace to keep the wrist in a neutral position may alleviate pressure on the median nerve and reduce symptoms, particularly at night.
- Activity Modification: Modifying or avoiding activities that exacerbate symptoms, such as repetitive hand movements or prolonged wrist flexion, can help prevent further irritation of the median nerve.
- Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) or corticosteroid injections may be prescribed to reduce pain and inflammation within the carpal tunnel.
- Physical Therapy: Performing stretching and strengthening exercises under the guidance of a physical therapist can improve wrist flexibility, muscle strength, and joint stability.
- Nerve Gliding Exercises: Gentle nerve gliding or flossing exercises may help mobilise the median nerve and alleviate symptoms by reducing adhesions and improving nerve mobility.
- Cold Therapy: Applying ice packs to the affected wrist for 15-20 minutes several times a day can help reduce pain and swelling associated with carpal tunnel syndrome.
- Ergonomic Modifications: Making ergonomic adjustments to workstations or tools, such as using wrist supports, ergonomic keyboards, or padded mouse pads, can minimise strain on the wrists and reduce the risk of exacerbating symptoms.
Outlook/Prognosis:
The outlook for individuals with carpal tunnel syndrome varies depending on the severity of symptoms, underlying medical conditions, and response to treatment. With appropriate management, many people experience significant improvement in symptoms and functional outcomes. However, in cases of advanced or persistent nerve compression, surgical intervention may be necessary to alleviate pressure on the median nerve and prevent long-term nerve damage. Early diagnosis, prompt intervention, and preventive strategies are essential for optimising outcomes and preserving hand function in individuals with carpal tunnel syndrome.