The Location of the Medial Humeral Epicondyle in Children

BACKGROUND: Medial humeral epicondyle fracture displacement in children is difficult to quantify, as current methods suffer from significant intraobserver and interobserver variability. The aim of this study was to create a systematic approach to determine medial epicondyle fracture displacement based upon easily identifiable radiographic landmarks of the elbow. METHODS: In this anatomic descriptive study, we evaluated 171 anteroposterior (AP) and lateral radiographs from children (4 to 15 years old) with a normal distal humerus. On the AP radiograph, the center of the medial epicondyle was compared with a line based upon the inferior olecranon fossa. On the lateral radiograph, the center of the medial epicondyle was compared with the posterior humeral line. RESULTS: On the AP radiograph, the average location of the center of the medial epicondyle was 0.5 mm inferior to the olecranon line (SD, 2.0 mm). On the lateral radiograph, the average location of the center of the medial epicondyle was 1.2 mm anterior to the posterior humeral line (SD, 1.2 mm). CONCLUSIONS: Our findings demonstrated a consistent radiographic position of the medial humeral epicondyle with little variation throughout skeletal maturation. CLINICAL RELEVANCE: This study may be helpful in assessing fracture displacement in pediatric medial epicondyle fractures.