In carpal tunnel syndrome, which fingers are most commonly affected?

• A. Entire hand
• B. Ring and little fingers
• C. Thumb only
• D. First three fingers of the hand, particularly at night

Answer: (D)

CTS happens when the median nerve is compressed inside the carpal tunnel. The sensory area of this nerve includes the thumb, index finger, middle finger, and the radial side of the ring finger. Because of this distribution, the most commonly affected digits are the first three fingers—the thumb, index, and middle fingers. Many people notice symptoms at night, since sleeping with the wrist bent can increase pressure in the carpal tunnel and intensify numbness or tingling in these digits. The little finger and the ulnar-side ring finger are less affected because they’re served by a different nerve, and the whole hand isn’t typically symptomatic.