Power grip of hand is due to
**Core Concept**
The power grip of the hand is a complex movement that involves the coordinated contraction of multiple muscles to generate a strong, precise grasp. This movement is primarily facilitated by the flexor digitorum profundus muscle, which is innervated by the ulnar nerve and the median nerve.
**Why the Correct Answer is Right**
The flexor digitorum profundus muscle plays a crucial role in the power grip by allowing the fingers to flex and grasp objects. The muscle's fibers are arranged in a way that allows for maximum force generation, making it essential for tasks that require a strong grip. The ulnar nerve and median nerve innervation ensures precise motor control, enabling the flexor digitorum profundus to work in conjunction with other muscles to achieve a stable and secure grasp.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the flexor pollicis longus muscle is primarily responsible for thumb flexion, not the power grip of the hand.
**Option B:** This option is incorrect because the palmaris longus muscle is a superficial muscle that assists in wrist flexion, but it is not directly involved in the power grip of the hand.
**Option C:** This option is incorrect because the extensor digitorum muscle is responsible for finger extension, which is the opposite movement of the power grip.
**Clinical Pearl / High-Yield Fact**
The flexor digitorum profundus muscle is also responsible for the "claw hand" deformity seen in patients with ulnar nerve damage, where the ring and little fingers are flexed and the other fingers are extended.
**Correct Answer: C. Flexor digitorum profundus muscle**