Fracture of lower one third of humerus impinging upon the radial nerve as it crosses from posterior compament to anterior compament crossing the lateral intermuscular septum is called as:
**Core Concept**
The question tests knowledge of **orthopedic anatomy** and **peripheral nerve injuries**, specifically the relationship between the **radial nerve** and the **humerus**. The radial nerve is particularly vulnerable to injury as it crosses the lateral intermuscular septum.
**Why the Correct Answer is Right**
The correct answer is related to the **radial nerve** and its course in the arm. As the radial nerve crosses from the posterior compartment to the anterior compartment, it is at risk of injury, especially with fractures of the lower one-third of the humerus. This type of injury can lead to **radial nerve palsy**.
**Why Each Wrong Option is Incorrect**
**Option A:** This choice is incorrect because it does not specifically relate to the radial nerve or its course.
**Option B:** This choice is also incorrect as it does not accurately describe the relationship between the radial nerve and the humerus.
**Option C:** This option is incorrect because it does not correctly identify the type of fracture or injury described.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the radial nerve is at risk with fractures of the mid to distal humerus, and **radial nerve palsy** can result, leading to weakness of wrist extension and finger extension.
**Correct Answer:** D. Holstein-Lewis fracture