Final answer:
The superficial layer of the posterior forearm consists of the extensor radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, and extensor carpi ulnaris, which are all crucial for wrist and finger extension.
Step-by-step explanation:
The muscles that make up the superficial layer of the posterior forearm, also known as the superficial posterior extensor compartment of the forearm, include several important muscles responsible for extending the wrist and fingers:
- Extensor radialis longus
- Extensor carpi radialis brevis
- Extensor digitorum
- Extensor digiti minimi
- Extensor carpi ulnaris
These muscles originate on the humerus and extend down to the hands, with their tendons supported by the superior extensor retinaculum. Their actions are fundamental for movements such as opening the hand or extending the fingers and wrist.