Final answer:
Wrist ulnar deviation involves muscles that act as agonists, like the flexor carpi ulnaris, to perform the movement, and antagonists like the flexor carpi radialis, which perform the opposite movement. The extensor carpi ulnaris also helps in ulnar deviation, while supination and pronation are related but distinct forearm movements.
Step-by-step explanation:
Understanding Wrist Ulnar Deviation
The terms agonist and antagonist are used to describe muscles that cause or inhibit a movement, respectively. In the context of wrist ulnar deviation, which involves moving the hand towards the ulna (the bone on the pinkie finger side of the arm), different muscles work as agonists and antagonists to control this motion. The flexor carpi ulnaris is a key agonist muscle that helps in flexing and adducting the hand at the wrist, which contributes to ulnar deviation. On the other hand, the extensor carpi ulnaris muscle, located in the superficial posterior compartment of the forearm, extends the wrist and also assists in ulnar deviation.
Conversely, muscles like the flexor carpi radialis and the extensor carpi radialis brevis work as antagonists in this context as they are involved in radial deviation - moving the hand towards the radius (the bone on the thumb side of the arm). The flexor carpi radialis bends the wrist towards the body and abducts the hand, while the extensor carpi radialis brevis aids in extending and abducting the wrist. Both muscles are located in the superficial anterior compartment of the forearm.
Additionally, supination and pronation are actions related to forearm and wrist movement. Supination is rotation of the forearm that positions the palm anteriorly, like holding a bowl of soup. Pronation positions the palm posteriorly. These movements are driven by the rotation of the radius around the ulna at the proximal and distal radioulnar joints.