A pediatric terrible triad fracture of elbow with lateral epicondyle avulsion.

A terrible triad fracture of the elbow is defined as an elbow dislocation with associated fractures of the coronoid process and radial head. This injury is uncommon in adults and exceptional in immature skeletons. We report a rare case of a terrible triad in a 14-year-old boy with a lateral epicondyle fracture. The diagnosis was suspected by the X-ray and confirmed by a CT scan after a closed reduction of the elbow, which was unstable. After a lateral approach of the elbow, the radial head and the lateral epicondyle were fixed by K-wire, and the fragment of the coronoid process was fixed by a bone suture. At two years of follow-up, the clinical and radiological outcomes were good. The terrible triad of the elbow is an exceptional trauma in children. Fracture avulsion of the lateral epicondyle is a particularity in the immature skeleton, equivalent to the lateral ligament injury in adults. A CT scan is mandatory after the reduction of the elbow to evaluate bone lesions. Open reduction by a single-lateral approach is indicated in cases of instability in extension.