**Question:** A 50-year-old male patient presented with a fracture as shown in the x-ray. On examination, there was paralysis of the most of the intrinsic muscles of the hand and loss of sensation from the medial 1.5 palmar surface of fingers. The Doctor carried out several tests to check the integrity of the nerve. All of the following nerves arise from the same cord from which the above injured nerve arises are except: -

A. Ulnar nerve
B. Radial nerve
C. Median nerve
D. Brachial plexus

**Correct Answer:** D. Brachial plexus

**Core Concept:** In the context of a spinal cord injury, we are discussing nerves that originate from the same spinal cord segment as the injured nerve. In the upper limb, the brachial plexus is formed by the union of spinal nerves from different spinal cord segments, not a single spinal cord segment.

**Why the Correct Answer is Right:** The injured nerve in this scenario is likely from the upper limb as the symptoms involve hand and finger function. In the upper limb, the nerves that arise from a single spinal cord segment are:

1. Ulnar nerve (C8, T1)
2. Radial nerve (C5, C6)
3. Median nerve (C5, C6)

**Why Each Wrong Option is Incorrect:**

A. Ulnar nerve (C8, T1) - This option involves nerves that arise from the same spinal cord segment as the injured nerve, which aligns with the correct answer.

B. Radial nerve (C5, C6) - Similar to ulnar nerve, this option involves nerves arising from the same spinal cord segment, making it incorrect.

C. Median nerve (C5, C6) - Similar to ulnar nerve and radial nerve, this option involves nerves arising from the same spinal cord segment, thus making it incorrect.

D. Brachial plexus (C5-C8 and T1) - The brachial plexus is formed by the union of spinal nerves from different spinal cord segments, not a single spinal cord segment.

**Clinical Pearl:**

In cases of spinal cord injury, it is essential to consider the segmental level of the injury and the corresponding nerves that arise from that level. Brachial plexus formation involves nerves from multiple spinal cord segments, making it an incorrect choice in this context.

**Why Each Wrong Option is Incorrect:**

A. Ulnar nerve (C8, T1) - The ulnar nerve arises from the same spinal cord segments as the injured nerve and should not be excluded.

B. Radial nerve (C5, C6) - Similarly to the ulnar nerve, the radial nerve arises from the same spinal cord segments as the injured nerve and should not be excluded.

C. Median nerve (C5, C6) - The median nerve also arises from the same spinal cord segments as the injured nerve and should not be excluded.

D. Brachial plexus (C5-C8 and T1) - The brachial plex