Question

Identify the marked muscle ‘A’ in the diagram:

• A. Brachioradialis
• B. Extensor carpi radialis longus
• C. Flexor carpi radialis
• D. Extensor carpi ulnaris

Answer 1

The Correct Option is B

The marked muscle 'A' in the diagram is the Extensor carpi radialis longus. This muscle is located in the forearm and is primarily responsible for extending and abducting the hand at the wrist joint.

To identify this muscle, it's important to consider its anatomical position and function:

• Anatomical Position: The extensor carpi radialis longus originates from the lateral supracondylar ridge of the humerus and inserts into the base of the second metacarpal bone.
• Function: It plays a key role in wrist extension and contributes to the abduction (radial deviation) of the wrist.

Here are some distinguishing features that help in identification:

• Its origin is above the lateral epicondyle, giving it a higher point of origin compared to other extensors.
• The muscle lies lateral to the extensor carpi radialis brevis and medial to the brachioradialis.

In conclusion, the combination of its anatomical origin, insertion, and function helps distinguish the extensor carpi radialis longus from other muscles in the forearm.