Which muscle flexes and abducts the wrist, originating from the medial epicondyle of the humerus and inserting on the bases of the 2nd and 3rd metacarpals?

• A. Brachioradialis
• B. Palmaris Longus
• C. Subscapularis
• D. Flexor Carpi Radialis

Answer: (D)

The main idea here is recognizing a forearm flexor that not only bends the wrist but also causes its radial (thumb-side) deviation, with a specific origin and insertion pattern. Flexor carpi radialis fits perfectly: it comes from the medial epicondyle of the humerus and inserts on the bases of the second and third metacarpals. Because it pulls on those metacarpal bases, it flexes the wrist and tends to move the hand toward the radius, producing abduction of the wrist.

Other options don’t match this combination. Brachioradialis acts primarily at the elbow rather than the wrist, and doesn’t insert on the metacarpal bases. Subscapularis is a shoulder muscle, not involved in wrist movements. Palmaris longus does originate from the medial epicondyle but inserts into the palmar aponeurosis, not onto the bases of the 2nd and 3rd metacarpals, and its role in wrist action is weaker and less about abducting the wrist.