Which nerve is most commonly compressed in carpal tunnel syndrome?

Which nerve is most commonly compressed in carpal tunnel syndrome?

• A. Ulnar nerve
• B. Median nerve
• C. Radial nerve
• D. Axillary nerve

Answer: (B)

The nerve most commonly affected in carpal tunnel syndrome is the one that travels through the carpal tunnel at the wrist. The carpal tunnel is a tight passage formed by the carpal bones and the flexor retinaculum, and it houses several flexor tendons plus the median nerve. When pressure rises inside this tunnel from swelling or inflammation, the median nerve becomes compressed, producing the classic symptoms: numbness or tingling in the thumb, index, middle, and the radial half of the ring finger, and often weakness or atrophy of the thumb muscles (thenar eminence) in more advanced cases. These signs help distinguish CTS from other nerve compressions that occur in different locations. For example, the ulnar nerve is typically compressed at Guyon’s canal near the wrist and would cause symptoms in the little finger and ulnar half of the ring finger, not the median nerve distribution; the radial nerve compressions occur along the forearm or dorsum of the hand and don’t produce the CTS pattern; the axillary nerve is a shoulder/upper arm nerve and wouldn’t present with wrist-level symptoms. So the median nerve is the one most commonly compressed in carpal tunnel syndrome.

The nerve most commonly affected in carpal tunnel syndrome is the one that travels through the carpal tunnel at the wrist. The carpal tunnel is a tight passage formed by the carpal bones and the flexor retinaculum, and it houses several flexor tendons plus the median nerve. When pressure rises inside this tunnel from swelling or inflammation, the median nerve becomes compressed, producing the classic symptoms: numbness or tingling in the thumb, index, middle, and the radial half of the ring finger, and often weakness or atrophy of the thumb muscles (thenar eminence) in more advanced cases. These signs help distinguish CTS from other nerve compressions that occur in different locations. For example, the ulnar nerve is typically compressed at Guyon’s canal near the wrist and would cause symptoms in the little finger and ulnar half of the ring finger, not the median nerve distribution; the radial nerve compressions occur along the forearm or dorsum of the hand and don’t produce the CTS pattern; the axillary nerve is a shoulder/upper arm nerve and wouldn’t present with wrist-level symptoms. So the median nerve is the one most commonly compressed in carpal tunnel syndrome.