Relevance of MRI for management of non-displaced lateral humeral condyle fractures in children

Abstract

INTRODUCTION: The treatment for non-displaced (<2 mm displacement) fractures of the lateral humeral condyle in children is controversial. Most studies recommend non-surgical treatment. However, plain radiographs are not sufficient to evaluate extension of the fracture line through the articular cartilage. This explains the high frequency of secondary displacements and non-unions, despite well-conducted conservative treatment. We hypothesized that MRI could be used to analyse whether the fracture is complete or incomplete. This could help to determine whether surgical or conservative treatment is indicated. MATERIAL AND METHODS: This prospective study enrolled children being treated for a non-displaced (< 2 mm gap) fracture of the lateral humeral condyle. All patients were treated with a long-arm cast in the emergency room. An MRI was done later on without sedation. A specific protocol was used to reduce the duration of the examination. T2-weighted and proton density fat-saturated sequences were used. RESULTS: Twenty-seven patients were enrolled: 16 boys and 11 girls with a mean age of 5 years (2-10). The MRI was performed an average of 7 days (1-23) after the fracture. The MRI could not be interpreted in two cases because the child had moved during the examination. In the other 25 patients, the fracture was incomplete in 17 patients and complete in 8 patients. Two children had secondary displacement diagnosed 7 and 11 days after the fracture event. These two patients underwent open reduction and internal fixation. There was no correlation between patient age and the fracture being complete or incomplete. There were no cases of non-union. CONCLUSION: MRI appears to be a reliable method for determining whether the fracture line is complete or incomplete. It can be performed without sedation, even in children as young as 2 years of age. Use of an injury-specific MRI protocol reduces the length of the examination, thereby improving its performance. We recommend that it be used to analyse non-displaced fractures of the lateral humeral condyle in children.