BACKGROUND. Most closed tibial fractures in children can be treated conservatively. On the occasions that surgical intervention is required, there are various options available to stabilise the fracture. We would like to present our experience of using monolateral external fixators in the management of closed tibial fractures. Aim. We sought to assess the time to healing, limb alignment, and complications observed in a cohort of tibial fractures treated with external fixation. METHODS. Our limb reconstruction database was used to identify patients who underwent monolateral external fixation for a closed tibial fracture between January 2008 and December 2016. Radiographs of all patients were assessed to determine the original fracture pattern. Time to union was assessed as the time when the fixator was removed and the patient allowed to mobilise independently without any further support of the limb. The presence or absence of residual deformity was assessed on final follow-up radiographs. RESULTS. 22 patients fulfilled the inclusion criteria. 78% of patients had both tibial and fibular fracture. The mean age at injury was 12 years. The mean time taken for the fracture to heal was 18 weeks. The total duration of follow-up averaged 9 months. The mean Valgus deformity at the final follow up was 4 degrees and the mean Varus deformity was 4 degrees. The mean procurvatum was 4.2 degrees and the mean recurvatum was 6 degrees. 50% of patients had pin site infection. Two patients had tibio fibular synostosis. None of them had leg length discrepancy or refractures. There were no episodes of osteomyelitis. CONCLUSIONS. Five degree of coronal plane deformity and ten degree of sagittal deformity were considered as acceptable in children due to their potential for remodeling. All our patients had acceptable levels of residual deformity. In our opinion monolateral external fixation represents a safe and effective option

Introduction. Proper rotational alignment of the tibial component in total knee arthroplasty (TKA) could be achieved using several techniques. The self adjustment methodology allows the alignment of the tibial component under the femoral component after several flexion-extension movements. Our hypothesis was that this technique allowed a posterior tibial component alignment parallel to the femoral component posterior bicondylar axis. The aim of this study was to access this hypothesis using a post-operative CT-scan study. Materials and Methods. This prospective CT-scan study involved 94 TKA. Theses TKA were divided in two groups: group1: 50 knees with a pre-operative genu varum deformity (mean HKA: 172.2°), operated using a medial parapatellar approach, and group 2: 44 knees with a preoperative valgus deformity (mean HKA: 188.7°), operated using a lateral parapatellar approach. Four measures were done on each post-operative CT-scan: angle between anatomical transepicondylar axis and femoral component posterior bicondylar axis (FCPCA), angle between FCPCA and tibial component marginal posterior axis, angle between tibial component marginal posterior axis and bony tibial plateau marginal posterior axis (BTPMPA), angle between transepicondylar axis and tibial component marginal posterior axis. Each measure was repeated, after one month by the same independent observer. Statistical evaluation used non-parametric Wilcoxon–Mann–Whitney test to compare each group of measures, and intraobserver reproducibility was assessed using ANOVA test, with an error rate of 5%. Results. Intraobserver measurements were reproducible. Mean FCPCA was to 3,1° (SD:1,91) in group 1 and 4,7° (DS: 2,96) in group 2. Tibial component was positioned in external rotation in both groups, in relation to FCPCA: (group 1: mean angle: 0,7° (SD:4,45), group 2: mean angle: 0,9° (SD:4,53)) and in relation to BTPMPA: (group1: mean angle: 6,1° (SD: 5,85); group2: mean angle: 12,5° (SD: 8,6)). There was no statistical difference between these two groups. Tibial component was positioned in internal rotation in relation to anatomical transepicondylar axis: (Group1: mean angle: 1,9° (SD: 4,93); group 2: mean angle: 3° (SD: 4.38)). Discussion. By using the self adjustment technique, tibial component is aligned parallel to the femoral component regardless of the initial frontal deformity and the surgical approach. However, there was a difference in tibial component axis and BTPMPA, between the two groups. This difference should be explained by the difference in morphology of the tibial plateau bone in knee with genu valgum deformity. The self adjustment technique is a reliable method to obtain a proper rotational alignment of the tibial component in TKA