Which wrist flexor is innervated by the median nerve?

Which wrist flexor is innervated by the median nerve?

• A. Flexor Carpi Ulnaris
• B. Flexor Carpi Radialis
• C. Extensor Carpi Radialis
• D. Flexor Digitorum Superficialis

Answer: (B)

The muscle that directly acts to flex the wrist and is innervated by the median nerve is the flexor carpi radialis. The median nerve supplies most of the forearm's superficial flexors, including this muscle, which crosses the wrist and flexes it while also contributing to radial deviation of the hand. The flexor carpi ulnaris, by contrast, is innervated by the ulnar nerve and is not a median-nerve muscle. The extensor carpi radialis is not a wrist flexor at all—it extends the wrist and is innervated by the radial nerve. The flexor digitorum superficialis is indeed innervated by the median nerve, but its primary role is flexing the proximal interphalangeal joints of the fingers; wrist flexion is a secondary action, so the most direct wrist flexor among the options is flexor carpi radialis.

The muscle that directly acts to flex the wrist and is innervated by the median nerve is the flexor carpi radialis. The median nerve supplies most of the forearm's superficial flexors, including this muscle, which crosses the wrist and flexes it while also contributing to radial deviation of the hand. The flexor carpi ulnaris, by contrast, is innervated by the ulnar nerve and is not a median-nerve muscle. The extensor carpi radialis is not a wrist flexor at all—it extends the wrist and is innervated by the radial nerve. The flexor digitorum superficialis is indeed innervated by the median nerve, but its primary role is flexing the proximal interphalangeal joints of the fingers; wrist flexion is a secondary action, so the most direct wrist flexor among the options is flexor carpi radialis.