Carpal Tunnel Syndrome

Carpal tunnel syndrome is a compressive neuropathy of the median nerve at the wrist. The nerve and flexor tendons pass through a confined space beneath the transverse carpal ligament. When pressure rises inside that space, the nerve's blood supply and function become impaired. Early compression produces intermittent tingling, numbness, or pain; prolonged or severe compression can progress to fixed sensory loss, weakness, axonal injury, and thenar muscle wasting. The symptom map is more informative than the word “hand pain.” Paresthesia usually involves the thumb, index finger, middle finger, and radial half of the ring finger. Symptoms may be worse at night or during sustained wrist flexion, gripping, or repetitive hand use. Aching can extend into the forearm, but forearm discomfort alone does not establish the diagnosis. Weak pinch, reduced grip, difficulty with buttons, or dropping objects suggests that motor function is being affected. Sensation over the thenar eminence is usually spared because the palmar cutaneous branch of the median nerve leaves the forearm before the nerve enters the carpal tunnel. Numbness over the thenar eminence, isolated little-finger symptoms, prominent neck...