Professional and Linguistic Assessments Board (PLAB) Practice Exam

Which nerve is injured in a Monteggia fracture?

1. Ulnar nerve

2. Median nerve

3. Radial nerve

4. Axillary nerve

The correct answer is: Radial nerve

In the context of a Monteggia fracture, the correct answer involves understanding the typical injuries associated with this specific type of fracture. A Monteggia fracture is characterized by an ulna fracture that occurs with an associated injury to the radial nerve. This injury occurs due to the proximity of the radial nerve to the ulna and its path around the elbow region, where it can be affected by the fracture displacement. When an ulna fracture occurs, especially in situations involving significant force or displacement, the radial nerve may be stretched or compressed, leading to dysfunction. This typically presents as wrist drop, where the affected individual is unable to extend their wrist or fingers, indicating weakness or paralysis of the extensor muscles. Other nerves listed—such as the ulnar nerve, median nerve, and axillary nerve—do not have the same direct association with a Monteggia fracture. The ulnar nerve is more commonly associated with fractures of the medial aspect of the elbow or injuries that affect the forearm. The median nerve is generally related to injuries at the level of the wrist or proximal forearm, while the axillary nerve pertains to shoulder injuries, particularly with humeral neck fractures. Therefore, the strong connection between the Monteggia fracture and radial