# Iatrogenic Ulnar Nerve Injury Post–K‐Wire Fixation of Supracondylar Humeral Fracture in a Child With Ulnar Nerve Instability: A Case Report and Review of the Literature

## TL;DR

A child developed nerve injury after a K-wire procedure for a humeral fracture due to an unstable ulnar nerve, highlighting the need for preoperative evaluation.

## Contribution

The case emphasizes the importance of preoperative assessment for ulnar nerve instability in children to prevent iatrogenic injury.

## Key findings

- Ulnar nerve injury occurred immediately after K-wire fixation in a child with nerve instability.
- Prompt surgical exploration and K-wire adjustment led to full recovery within four weeks.
- Preoperative evaluation of ulnar nerve stability can help prevent such injuries.

## Abstract

Iatrogenic ulnar nerve damage is not an uncommon consequence after K‐wire fixation of supracondylar humeral fractures in children. The risk of injury may be increased when the ulnar nerve is hypermobile.

We present a 7‐year‐old boy who underwent closed reduction and crossed K‐wire fixation for a Gartland Type IIb supracondylar fracture of the right humerus. The ulnar nerve was not palpable in the cubital tunnel but felt as a cord‐like structure in front of the medial epicondyle. Immediately following surgery, the patient developed paresthesia and painful incomplete clawing of the ring and little fingers. Exploration on the second day of surgery revealed the ulnar nerve anterior to the medial epicondyle and tented over the K‐wire. The K‐wire was replaced with one more lateral pin, and the nerve was decompressed. Complete recovery of nerve injury was noticed 4weeks after exploration.

Given the greater prevalence of ulnar nerve instability among children, it is prudent to preoperatively evaluate patients for evidence of ligament laxity or ulnar nerve instability of the contralateral normal elbow. Prompt exploration and K‐wire removal can confirm nerve continuity, reassure the family, and ensure swift recovery from nerve injury.