Which muscle is not supplied by ulnar nerve
**Core Concept**
The ulnar nerve is a branch of the brachial plexus that innervates several muscles in the forearm and hand. It plays a crucial role in forearm and hand movements, particularly in the medial aspect. Understanding the motor innervation of the ulnar nerve is essential in diagnosing and managing nerve injuries.
**Why the Correct Answer is Right**
The ulnar nerve supplies the flexor carpi ulnaris, flexor digitorum profundus (to the little and ring fingers), and the intrinsic muscles of the hand, including the hypothenar muscles, the adductor pollicis, and the medial two lumbricals. However, it does not innervate the extensor digitorum, which is a key muscle involved in finger extension.
**Why Each Wrong Option is Incorrect**
* **Option A:** Flexor carpi ulnaris is actually supplied by the ulnar nerve, so this option is incorrect.
* **Option B:** Flexor digitorum profundus (to the little and ring fingers) is also supplied by the ulnar nerve, making this option incorrect as well.
* **Option D:** The intrinsic muscles of the hand, including the hypothenar muscles, are supplied by the ulnar nerve, so this option is incorrect.
**Clinical Pearl / High-Yield Fact**
When assessing a patient with suspected ulnar nerve injury, it's essential to note that the ulnar nerve typically spares the medial two lumbricals, which are supplied by the median nerve. This can help distinguish ulnar nerve injuries from median nerve injuries.
**Correct Answer:** C.