Ulnar nerve snagged on Kirschner wire following surgery for supracondylar fracture of humerus.

A 9-year-old boy fell off his skateboard, resulting in a supracondylar fracture of his left humerus. The fracture was surgically repaired on the same day using two Kirschner wires inserted from the medial and lateral sides. Following surgery, the patient developed ulnar nerve palsy, prompting reoperation. It was discovered that the ulnar nerve was located anterior to the medial epicondyle and was snagged on the Kirschner wire, causing compression. Despite clear confirmation of the wire entry site, the presence of an unstable ulnar nerve anterior to the medial epicondyle necessitates caution to prevent ulnar nerve injury.