Most common associated injury of fracture medial epicondyle:
**Core Concept**
Fracture of the medial epicondyle is a type of elbow fracture that involves the medial aspect of the distal humerus. The medial epicondyle is a bony prominence that serves as the origin of the flexor muscles of the forearm. The most common associated injury with this type of fracture is related to the surrounding soft tissues and nerves.
**Why the Correct Answer is Right**
The most common associated injury of fracture medial epicondyle is the ulnar nerve injury. This is because the ulnar nerve is closely related to the medial epicondyle and runs in close proximity to it. The ulnar nerve can be damaged during the fracture process, leading to symptoms such as numbness, tingling, and weakness in the hand. The mechanism of injury can cause the ulnar nerve to stretch or even get compressed, leading to nerve damage.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not relate to the most common associated injury with fracture medial epicondyle. While radial head fracture is a common injury in the elbow, it is not typically associated with medial epicondyle fractures.
* **Option B:** This option is incorrect because it is not a direct consequence of fracture medial epicondyle. While medial epicondyle fractures can cause elbow instability, this is not the most common associated injury.
**Clinical Pearl / High-Yield Fact**
It is essential to evaluate the ulnar nerve function in patients with fracture medial epicondyle, as ulnar nerve injury can lead to significant morbidity. A thorough physical examination, including testing of nerve function, should be performed to identify any potential nerve damage.
**Correct Answer:** C. Ulnar nerve injury