Question in Kinesiology What is neutralizer, fixator and stabilizer muscles of wrist flexion, wrist extension and finger flexion?
The correct answer and explanation is:
Neutralizer, Fixator, and Stabilizer Muscles in Wrist Flexion, Wrist Extension, and Finger Flexion
Wrist Flexion:
- Neutralizers: During wrist flexion, the finger flexors (like flexor digitorum superficialis and flexor digitorum profundus) can cause unwanted finger movement. Neutralizer muscles such as the extensor digitorum contract to prevent finger flexion and isolate wrist flexion.
- Fixators: The muscles that stabilize the forearm and wrist joints during wrist flexion are often the pronator teres and brachioradialis. They fix the forearm position to allow smooth wrist flexion.
- Stabilizers: The wrist extensors (extensor carpi radialis longus and brevis, extensor carpi ulnaris) act as stabilizers to maintain the wrist in a neutral or slightly extended position, preventing excessive wrist deviation and allowing effective wrist flexion.
Wrist Extension:
- Neutralizers: The wrist extensors, such as extensor carpi radialis longus and brevis, when acting alone, may also cause radial or ulnar deviation. The wrist flexors (flexor carpi radialis and flexor carpi ulnaris) serve as neutralizers by preventing unwanted wrist flexion and deviation, helping to focus movement on wrist extension.
- Fixators: The forearm muscles like pronator teres and supinator help to stabilize the forearm and elbow, providing a steady base for wrist extension.
- Stabilizers: Wrist flexors stabilize the wrist joint by preventing excessive extension or deviation, maintaining joint alignment during wrist extension.
Finger Flexion:
- Neutralizers: To flex the fingers without unwanted wrist movement, the wrist extensors (extensor carpi radialis longus and brevis, extensor carpi ulnaris) contract as neutralizers to prevent wrist flexion, isolating finger flexion.
- Fixators: The forearm muscles (pronator teres, supinator) help stabilize the forearm during finger flexion.
- Stabilizers: Wrist flexors act as stabilizers by holding the wrist in a neutral or slightly flexed position, preventing hyperextension of the wrist during finger flexion.
Explanation:
In kinesiology, muscles rarely act in isolation; often, the primary mover (agonist) is assisted by other muscles that prevent undesired actions. Neutralizers counteract unwanted secondary movements caused by the agonist. Fixators stabilize the origin of the agonist muscle, providing a firm base so the agonist can act efficiently. Stabilizers help maintain posture or joint position during movement.
For wrist flexion, finger flexors also pull on the fingers, which can cause unwanted finger movement. Extensors neutralize this by preventing finger flexion. Conversely, when flexing the fingers, wrist extensors contract to keep the wrist stable and neutral, preventing wrist flexion.
The fixators, usually muscles around the elbow and forearm, hold the limb steady, allowing the wrist and fingers to move precisely. Stabilizers are often muscles that maintain joint alignment to maximize force efficiency and prevent injury.
This coordinated action between neutralizers, fixators, and stabilizers allows smooth, controlled, and precise movements of the wrist and fingers, essential for daily tasks and fine motor control.