Final answer:
The interosseous membrane and fascial septa separate the anterior and posterior compartments of the forearm, with the former housing flexor muscles and the latter housing extensor muscles.
Step-by-step explanation:
The interosseous membrane of the forearm and the fascial septa are the key anatomical structures that separate the anterior and posterior compartments of the forearm. The anterior compartment primarily houses flexor muscles like the flexor digitorum superficialis and the flexor digitorum profundus. These muscles are involved in flexing the digits and the wrist, and they originate on the humerus and insert onto parts of the hand. The deep anterior compartment of the forearm is crucial for finger flexion and fist formation.
The superficial posterior compartment of the forearm includes extensor muscles such as extensor radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, and extensor carpi ulnaris. These muscles work to extend the wrist and fingers, straightening them away from the body, and are important for movements like tilting the hand to the side. Both compartments are grouped based on the primary actions of the muscles contained within them - flexion in the anterior, and extension in the posterior. They're innervated by different branches of the brachial plexus, which signals their functional diversity.