In suspected carpal tunnel syndrome, which symptom is most characteristic?

• A. Numbness/tingling in the thumb, index, middle, and radial half of ring finger, worse at night
• B. Numbness in the little finger only
• C. Pain in the ankle
• D. Weakness of knee extension

Answer: (A)

The hallmark is sensory symptoms in the median nerve distribution of the hand, especially at night. Numbness and tingling in the thumb, index, middle, and the radial half of the ring finger reflect median nerve compression at the carpal tunnel, and symptoms often worsen when the wrist is flexed during sleep. The little finger is spared because it’s supplied by the ulnar nerve, not the median nerve. Pain in the ankle or weakness of knee extension involve other nerves and aren’t related to carpal tunnel syndrome. In other words, the distribution and nocturnal pattern of numbness/tingling in those specific digits is the most characteristic clue.