Carpal Tunnel Syndrome (CTS) is a common entrapment neuropathy caused by the compression of the median nerve as it passes through the wrist’s carpal tunnel. This narrow tunnel on the anterior side of the wrist serves as a passage for tendons and the median nerve into the hand. When pressure builds in this space, often due to repetitive strain or injury, it can cause significant discomfort, numbness, and weakness in the hand. CTS typically occurs in people aged 36-60, with women being more commonly affected. Understanding CTS’s causes, symptoms, and treatment options is essential for preventing long-term complications.
What is Carpal Tunnel Syndrome?
Carpal Tunnel Syndrome occurs when pressure is exerted on the median nerve at the wrist. This pressure can arise from various factors, including genetic predisposition, repeated wrist movements, or injuries. The median nerve, responsible for sensations in the thumb, index finger, middle finger, and part of the ring finger, becomes compressed, leading to symptoms like tingling and numbness in these areas. Without treatment, CTS can lead to muscle weakness and atrophy, affecting daily functions like gripping objects.
Anatomy of the Carpal Tunnel
The carpal tunnel is formed by a sturdy, non-expandable structure that provides protection to the median nerve and nine tendons. It comprises two main layers: the carpal arch and the flexor retinaculum. The carpal arch creates a concave surface, which, when bridged by the flexor retinaculum, forms the tunnel. Within this narrow space lie the tendons of the flexor pollicis longus, four flexor digitorum profundus tendons, four flexor digitorum superficialis tendons, and the median nerve. Additionally, the palmar cutaneous branch of the median nerve, running superficially to the flexor retinaculum, is a key component, as any compromise here can contribute to CTS.
Causes and Pathophysiology
CTS can result from an array of factors. These include:
Reduced Tunnel Size: Conditions like mechanical overuse, osteoarthritis, or trauma can decrease the carpal tunnel space.
Increased Tunnel Contents: Swelling within the tunnel due to ganglion cysts, primary nerve sheath tumors, or rheumatoid arthritis-related synovial hypertrophy can crowd the space and compress the nerve.
Increased Tunnel Pressure: Localized swelling, blockage of venous outflow, or excessive fluid retention (often seen during pregnancy) can raise pressure on the median nerve.
Inflammation of Tendons: The nine tendons within the tunnel can become inflamed, which may compress the nerve.
Other risk factors include repetitive wrist movements (typing, assembly line work), obesity, diabetes, cumulative trauma disorders, autoimmune conditions (like rheumatoid arthritis), and hypothyroidism.
Symptoms and Clinical Presentation
CTS symptoms often start gradually and can include tingling, numbness, or a burning sensation along the median nerve’s distribution in the hand. Patients often find that these symptoms worsen when they grip objects, such as phones or steering wheels, and some may temporarily relieve symptoms by shaking or flicking their hand. As CTS progresses, it can cause constant tingling, numbness, and pain, eventually leading to weakness in the thenar muscles at the base of the thumb. Advanced cases can result in a reduced grip strength, clumsiness, and the tendency to drop objects.
Diagnosis
CTS diagnosis involves evaluating symptoms and conducting physical tests. Phalen’s test is commonly used: the patient flexes both wrists while pressing the dorsal sides of the hands together for one minute. If paresthesia occurs, it indicates a positive test.
Additionally, it’s crucial to differentiate CTS from other conditions with similar symptoms. Differential diagnoses may include:
Other Median Nerve Entrapment Syndromes: Such as anterior interosseous nerve syndrome.
Cervical Radiculopathy: Nerve root issues in the neck affecting arm sensation.
Median Neuropathy in the Fore arm Brachial Plexopathy: Involving nerves that pass through the shoulder.
Musculoskeletal Conditions: Such as osteoarthritis and rheumatoid arthritis.
Vascular Conditions: Circulation issues that may cause numbness or weakness.
Treatment Options
Treatment varies based on the severity of CTS symptoms and may include non-surgical and surgical approaches.
Wrist Splints: A common initial treatment, wrist splints are worn at night to hold the wrist in a neutral position, helping prevent nighttime symptoms. While effective in the short term, it’s essential to exercise the wrist during the day to prevent muscle weakening.
Medications: NSAIDs, such as ibuprofen or naproxen, are often prescribed to reduce pain and inflammation. For severe cases, corticosteroids may be injected locally into the carpal tunnel, providing more significant relief than oral forms.
Surgery: Surgical intervention is generally considered when other treatments fail, or the condition has reached an advanced stage. The most common procedure is carpal tunnel release surgery, which involves cutting the flexor retinaculum to relieve pressure on the median nerve. This surgery can be performed through either an open or endoscopic approach.
Conclusion
Carpal Tunnel Syndrome can significantly affect a person’s quality of life, especially if left untreated. Early intervention with splints, lifestyle adjustments, and medications can help alleviate symptoms and prevent further complications. If you suspect CTS, it’s essential to consult a healthcare provider for diagnosis and to discuss appropriate treatment options tailored to your needs.
Explore more blogs