Median nerve lesion at the wrist causes all of the following. except –
**Core Concept**
A median nerve lesion at the wrist affects the motor and sensory functions of the hand, specifically involving the **thenar muscles** and the **lateral two-thirds of the palm**. The **median nerve** supplies the ** opponens pollicis**, **abductor pollicis brevis**, and **flexor pollicis brevis** muscles.
**Why the Correct Answer is Right**
Since the question is incomplete, let's discuss a common consequence of median nerve lesion at the wrist: **thenar atrophy** and **loss of opposition**. The median nerve lesion leads to weakness in thumb opposition due to the involvement of the **thenar muscles**.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific option provided, it's challenging to address each choice directly. However, typically, options might include sensory loss in the distribution of the median nerve, which is correct, or motor weakness, which is also correct.
**Option B:** Similarly, without the specific text, we can't directly refute it, but median nerve lesions do cause specific patterns of sensory and motor loss.
**Option C:** Again, lacking the specific option, a common incorrect statement might relate to the unaffected areas or functions, such as the **hypothener muscles** which are supplied by the **ulnar nerve**.
**Option D:** This option might incorrectly state an unaffected function or area, such as the **dorsum of the hand** which is primarily supplied by the **radial nerve**.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that a median nerve lesion at the wrist typically spares the **flexor carpi radialis** and **palmaris longus**, as these are innervated more proximally.
**Correct Answer:** Correct Answer: D. Loss of wrist extension