A 35-year-old woman is evaluated in the office for a 5-month history of right-hand numbness and tingling. She says that these symptoms involve the entire hand, seem to be worse when she drives or holds a book or newspaper, and have been awakening her at night. She reports no history of neck pain or hand weakness. Personal and family medical histories are noncontributory, and she takes no medication.
General physical examination reveals no abnormalities. Neurologic examination shows normal strength but sensory loss in the first three digits and the radial half of the fourth digit in the right hand.
This patient most likely has carpal tunnel syndrome. Carpal tunnel syndrome refers to median nerve compression at the wrist in the carpal tunnel. Symptoms include aching wrist pain with sparing of the palm, numbness and tingling in the median nerve sensory distribution of the fingers, and weakness of the thenar muscles. The paresthesias are often worse at night or when holding a book or steering a car.
de Quervain tenosynovitis is an exercise-related injury associated with knitting and sports involving extensive wrist action. Tenderness may be elicited in the anatomic snuffbox (the extensor pollicis brevis and abductor pollicis longus tendons). Pain elicited by flexing the thumb into the palm, closing the fingers over the thumb, and then bending the wrist in the ulnar direction (Finkelstein test) is confirmatory.
Ganglion cysts are synovia-filled cysts arising from joints or tendon sheaths that typically appear on the dorsal hand or ventral wrist. They can cause pain and compress other structures. The absence of cystic structures on the dorsal and ventral wrist and the distribution of the patient's pain eliminate this diagnosis.
Ulnar nerve compression at the wrist is also called Guyon tunnel syndrome, because the entrapment occurs where the ulnar nerve transverses the Guyon tunnel between the pisiform and hamate bones on the anterolateral side of the wrist, and cyclist's palsy, because the compression of the ulnar nerve often occurs as the hand rests on the handlebars. However, the ulnar nerve can be compressed by muscles, tumors (lipomas), scar tissue, synovial cysts, or any other internal structure that passes close to the tunnel. The presentation is similar to that of carpal tunnel syndrome, but with symptoms and signs on the ulnar distribution of the hand.
- Symptoms of carpal tunnel syndrome include aching wrist pain with sparing of the palm, numbness and tingling in the median nerve sensory distribution of the fingers, and weakness of the thenar muscles.