The Initial Characteristics of Paediatric Supracondylar Humerus Fractures Led to Cubitus Varus Deformity and Delayed Displacement

Background: Supracondylar humerus fractures are the most common type of elbow fracture in children, with a variety of complications such as cubitus varus deformity. The most important goal of the initial treatment is to avoid complicated deformities. In the present study, we investigated cubitus varus deformity and discussed the ideal initial treatment for supracondylar humerus fractures. Methods: There were 58 conservative cases (26 girls and 32 boys) and 115 operative cases (40 girls and 75 boys) with supracondylar humerus fractures. We evaluated the correlation between the following factors on injury in the conservative cases: Gartland classification, presence of comminuted medial fractures, medial shift length, anterior spike length, age, sex, affected side (as explanatory variables) and the factors of cubitus varus deformity as response variables by using the linear regression model for multivariable analysis. Moreover, we evaluated the changes in displacement after the operation in the operative cases, adding the presence of medial pins and the number of pins as explanatory variables. Results: Injury severity (Gartland classification) was a significant factor for cubitus varus deformity. The presence of comminuted bone fragments on the medial side, anterior spike length, age, sex and affected side were not significant factors of cubitus varus deformity. However, medial displacement on injury was a significant factor of both cubitus varus deformity. In the operative case study, medial displacement was a significant factor in cubitus varus deformity. The presence of comminuted bone fragments on the medial side, number of pins and age were also significant factors for cubitus varus deformities. Conclusions: The present study concluded that it is important to perform accurate reduction and fixation, with special attention to medial shift and medial comminuted fragments to avoid cubitus varus deformity. Level of Evidence: Level IV (Therapeutic)