Analysis of risk factors for re-displacement of pediatric tibia fractures: A retrospective study of 196 cases.

Objective: The aims of this study were (1) to analyze the factors that may cause loss of reduction (LOR) in pediatric tibia diaphysis and distal third fractures treated with closed reduction and casting (CRC) and (2) to determine the effectiveness of cast index (CI), gap index (GI), and three-point index (TPI) in prediction of LOR.

Methods: The patients aged 0-16 years who were admitted to the emergency department between January 2014 and January 2018, with tibia diaphysis or distal third fractures and treated with CRC were included the study. A total of 196 pediatric patients (41 females, 155 males) were retrospectively evaluated. The radiographs on admission were analyzed in terms of fracture type, location of the fracture, presence/location of the fibula fracture as well as initial angulation in both planes, translation, and the time of definitive cast. On radiographs taken after closed reduction and final casting, angulation in the coronal and sagittal planes, amount of translation (%), CI, GI, and TPI were measured. Logistic regression analysis was used to evaluate the risk factors of re-displacement.

Results: Of 196 patients, 46 developed re-displacement (23%). Age (P : 0.029), initial translation (P : 0.006), post-reduction translation (P : 0.001), and post-reduction AP angulation (P : 0.002) were found statistically significant. Mean CI and GI were higher in re-displacement group (P : 0.033, 0.036, respectively). According to multivariate logistic regression analysis postreduction AP angulation, post-reduction translation, and cast index were found independent risk factors.

Conclusion: One should carefully evaluate patients who underwent CRC due to tibia fracture with CI > 1.02, post-reduction AP angulation > 3.4°, and post-reduction translation > 24.3° in terms of occurrence of re-displacement.

Level of evidence: Level IV, Therapeutic Study.