**Question:** A 12-year-old child presents with tingling sensation and numbness in the little finger and gives history of fracture in the elbow region 4 years back. The probable fracture is

A. Radial Collateral Ligament (RCL)
B. Radial Tunnel
C. Radial Nerve Tunnel
D. Brachial Artery Tunnel

**Correct Answer:** **C. Radial Nerve Tunnel**

**Core Concept:**
The radial nerve (C8, T1) is a vital structure in the upper limb that arises from the brachial plexus and innervates muscles involved in finger extension, thumb opposition, and sensation in the ulnar half of the hand. The radial nerve also passes through several tunnels, most notably the **radial tunnel** (also known as the **radial canal** or **Radial Nerve Tunnel**) in the elbow joint.

**Why the Correct Answer is Right:**
The radial nerve passes through the radial tunnel in the elbow and sustains compression or injury due to the fracture. In this case, the fracture happened 4 years ago, which is a long period for the symptoms to appear. This indicates that the injury to the radial nerve occurred during the elbow fracture and the tingling and numbness in the little finger are a result of radial nerve compression within the radial tunnel.

**Why Each Wrong Option is Incorrect:**

A. Radial Collateral Ligament (RCL) is a structure related to knee joint stability, not the elbow or radial nerve.
B. Radial Tunnel (radial nerve canal) is the correct term for the tunnel where the radial nerve passes through the elbow joint, but it does not explain the cause of the symptoms in this case.
D. Brachial Artery Tunnel refers to the carpal tunnel in the wrist, which is unrelated to the symptoms in this scenario.

**Clinical Pearl:**
The **Radial Nerve Tunnel** is a crucial anatomic structure to understand for upper limb injuries and symptoms. In cases of radial nerve compression, it is essential to examine the history of trauma or fracture in the elbow region, as seen in this scenario.