Which of the following lists contains the muscles that contribute to wrist extension?

Which of the following lists contains the muscles that contribute to wrist extension?

• A. Abductor pollicis longus and extensor pollicis brevis
• B. Extensor carpi ulnaris, extensor digitorum, extensor carpi radialis longus and extensor carpi radialis brevis
• C. Flexor carpi radialis, flexor digitorum profundus
• D. Flexor carpi ulnaris and extensor carpi ulnaris

Answer: (B)

Wrist extension is generated by muscles on the back of the forearm that cross the wrist and pull the hand backward. The main wrist extensors are the extensor carpi radialis longus, extensor carpi radialis brevis, and extensor carpi ulnaris. The extensor digitorum also crosses the wrist and can contribute to wrist extension when the fingers are extended or stabilized. Together, these muscles form the primary group responsible for extending the wrist, making the set that includes ECU, ECRL, ECRB, and EDC the best match. The other options include wrist flexors or thumb-focused muscles, which do not drive wrist extension as their main action.

Wrist extension is generated by muscles on the back of the forearm that cross the wrist and pull the hand backward. The main wrist extensors are the extensor carpi radialis longus, extensor carpi radialis brevis, and extensor carpi ulnaris. The extensor digitorum also crosses the wrist and can contribute to wrist extension when the fingers are extended or stabilized. Together, these muscles form the primary group responsible for extending the wrist, making the set that includes ECU, ECRL, ECRB, and EDC the best match. The other options include wrist flexors or thumb-focused muscles, which do not drive wrist extension as their main action.