Ulnar nerve injury at wrist spares which muscle
**Core Concept**
The ulnar nerve innervates several muscles in the hand, but its course and branching pattern determine which muscles are spared in the event of injury at the wrist. The **ulnar nerve** divides into a superficial and a deep branch, with the latter supplying most of the intrinsic hand muscles.
**Why the Correct Answer is Right**
Since the question is incomplete, let's consider the general principle: an ulnar nerve injury at the wrist would spare muscles innervated by branches that originate more proximally. The **flexor carpi ulnaris** and **half of flexor digitorum profundus** are typically innervated before the ulnar nerve reaches the wrist.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option, it's hard to say, but generally, any muscle innervated by the ulnar nerve distal to the wrist would be affected.
**Option B:** Similarly, without specifics, we can't determine its correctness, but if it's a muscle typically innervated by the ulnar nerve at or near the wrist, it would likely be affected.
**Option C:** and **Option D:** follow the same logic, with their correctness depending on the specific muscle in question.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the **adductor pollicis**, **interosseous muscles**, and **medial two lumbricals** are typically affected by ulnar nerve injuries at the wrist, as they are innervated by the deep branch of the ulnar nerve.
**Correct Answer:** Not provided due to incomplete question.