Carpal Tunnel Syndrome

What is Carpal Tunnel Syndrome?

The carpal tunnel is a narrow passage at the wrist, formed by bones and ligaments, through which the median nerve and several flexor tendons pass. When pressure builds inside this tunnel, the median nerve becomes compressed. The result is tingling, numbness, and weakness in the thumb, index, middle, and part of the ring finger, which are the areas this nerve supplies.

Carpal tunnel syndrome is the most common nerve entrapment condition in the upper limb. Repetitive wrist movements, prolonged keyboard use, and vibrating tools are typical occupational triggers. Underlying conditions including diabetes, hypothyroidism, rheumatoid arthritis, and pregnancy-related fluid retention all raise the pressure inside the tunnel and are common contributing factors.

Mild cases cause intermittent tingling, usually worse at night. More severe or longstanding compression produces persistent numbness and loss of grip strength. Nerve conduction studies confirm the diagnosis and indicate how advanced the compression is.

Symptoms

• Tingling and numbness in the thumb, index, and middle fingers
• Symptoms that wake you at night, often relieved by shaking the hand
• Weakness in grip and difficulty with fine finger tasks
• Pain at the wrist radiating up the forearm
• Dropping objects due to reduced hand sensation or strength
• Wasting of the muscle at the base of the thumb in advanced cases

How We Treat It

Ultrasound-guided steroid injection around the median nerve inside the carpal tunnel is an effective, well-evidenced treatment. The ultrasound guidance allows us to place the injection precisely alongside the nerve without entering the nerve sheath itself, which is both safer and more effective than landmark-based injection. It reduces the inflammation and swelling compressing the nerve, and relief often lasts several months. For some patients, a single injection is sufficient and symptoms do not return.

For cases where the nerve is entrapped by scar tissue or where injection response has been temporary, ultrasound-guided hydrodissection uses fluid to free the nerve from surrounding adhesions. This is increasingly preferred over surgical decompression for moderate cases. Wrist splinting overnight is recommended alongside any procedure to reduce mechanical stress on the nerve during recovery.