An approach to determine the coronal plane deformity of the distal tibia intraoperatively in the treatment of tibial fracture with intramedullary nail fixation

Abstract

Background To develop a new approach to determine the existence of coronal plane deformity (valgus and varus) intraoperatively in the treatment of tibial fracture with closed reduction and intramedullary nail fixation. Methods A retrospective analysis was conducted by enrolling 33 consecutive patients with tibial fracture who underwent closed reduction and intramedullary nail fixation from January 2018 to January 2019 in our trauma center. There were 23 males and 10 females aged from 22 to 69 years old with an average of 41.3. The standard anteroposterior and lateral preoperative radiographs were performed routinely. After insertion of the tibial intramedullary nail through the standard entry point intraoperatively, the parallel relationship between the distal horizontal interlocking screw and the tibiotalar joint surface on the anteroposterior fluoroscopy was used to determine the occurrence of valgus or varus deformity of the distal tibial fragment. Results 33 patients were postoperatively followed up for 13 to 25 months (mean 18.7 months). The fractures achieved bone union in 4.3 months by average (ranging from 3 to 6 months). The lateral distal tibial angle (LDTA) of the unaffected side which is measured postoperatively was 87.3°-89.6 ° (average 88.7 °± 0.8°), and the LDTA of the affected side was 87.5°-90.4°(average 88.9°± 1.1°). There was no statistically significant difference between the unaffected side and the affected side (t=-1.865, p=0.068). The intraoperative measurement indicated 6 cases of valgus angulation and 3 cases of varus angulation deformities, and all the deformities were corrected accordingly during the surgery. According to the Olerud-Molander Ankle Score, the clinical outcomes demonstrated 22 excellent cases, 8 good cases, 2 fair cases, and 1 poor case of all the fractures at 12 months after surgery. Conclusion During closed reduction and intramedullary nail fixation for tibial fractures, the parallel relationship between the distal horizontal interlocking screw and the tibiotalar joint surface on the intraoperative anteroposterior films showed the better discriminative ability to determine the onset of valgus or varus deformity of the distal tibial fragment after the tibial intramedullary nail inserted through the standard entry point.Level of Evidence: Level IV, case series study.