Analysis Of Factors Influencing Clinical Effect Of The Treatment Of Closed Tibial Pilon Fractures

Part One Development of a nomogram to predict surgical site infectionafter open reduction and internal fixation for closed pilonfractureBackground: To explore the risk factors and develop a nomogram in order to predict surgical site infection(SSI)after open reduction and internal fixation(ORIF)for closed pilon fractures(CPFs).Methods: A prospective cohort study with one-year follow-up was carried out in a provincial trauma center.From January 2019 to January 2021,417 adult patients with CPFs receiving ORIF were enrolled.A Whitney U test or t-test,Pearson chi-square test,and multiple logistic regression analyses were gradually used for screening the adjusted factors of SSI.A nomogram model was bulit to predict the risk of SSI,and the concordance index(C-index),the receiver operating characteristic(ROC)curve,calibration curve and decision curve analysis(DCA)were used for evaluating the prediction performance and consistency of the nomogram model.The bootstrap method was employed to test the validity of the nomogram.Results: The incidence of SSI after ORIF for CPFs was 7.2%(30/417):4.1%(17/417)of superficial SSIs and 3.1%(13/417)of deep SSIs.The most common pathogenic bacteria were staphylococcus aureus(36.6%,11/30).The multivariate analysis showed tourniquet use,longer preoperative stay,lower preoperative albumin(ALB),higher preoperative body mass index(BMI)and hypersensitive C-reactive protein(HCRP)were independent risk factors of SSI.Additionally,the C-index and bootstrap value of the nomogram model was 0.838 and 0.820,respectively.Finally,the calibration curve indicated that the actual diagnosed SSI had good consistency with the predicted probability,and the DCA showed that the nomogram had clinical value.Conclusions: Tourniquet use,longer preoperative stay,lower preoperative ALB,higher preoperative BMI and Hs-CRP were five independent risk factors of SSI after closed pilon fractures treated by ORIF.These five predictors are shown on the nomogram,with which we may be able to further prevent the CPF patients from SSI.Part Two Clinical effect of fibular fixation in patients with closed tibial pilon fracturesBackground: There is a lack of consensus about the role of fibula fixation in the closed tibial pilon fractures.We hypothesize that the fibula fracture need not be fixed in the closed tibial pilon fractures if primary stability can be achieved with tibial fixation alone.Methods: We reviewed 161 patients with operatively treated closed tibial pilon fracture from January 2020 to January 2021.All these patients must have an associated fibula fracture.We divided them into two groups: case group and control group.The case group included patients with fibular fixation.The control group included patients without fibular fixation.The primary outcome measure was any fracture related complications.Secondary outcomes were wound complications and other morbidities.Results: We enrolled 161 patients eligible to this study.There were 112(69.6%)patients with fibula fixation and 49(30.4%)patients without fixation at the time of closed pilon fracture treatment.The average age of our entire study population was 47.17±14.52 years old.There were 101(62.7%)men.More than half of the patients(53.4%)sustained these fractures from high velocity injuries.The mean follow-up duration is 13.45±3.60 months.In terms of AO/OTA classification,119(73.9%)had type B fractures and 42(26.1%)had type C fractures,no patient had type A fracture.All patients had locking plate fixation for the tibia pilon fractures.The most common fibula fracturepatterns were the oblique type at 82(50.9%)patients,60(37.3%)patients with comminuted type and least common transverse type at 19(11.8%)patients.In terms of fracture related complications(nonunion,delayed union,malunion)rates for the entire cohort,there were 6(3.7%)patients who had nonunion,12(7.5%)had delayed union,43(26.7%)had malunion.Nine patients(5.6%)experienced a surgical site infection,six of them(3.7%)had superficial surgical site infections,three of them(1.9%)had deep surgical site infections.No patienrs developed osteomyelitis.There were 2(1.2%)patients who experienced failure of internal fixation.The fracture related complications rates were 38.4% in the case group and 36.7% in the control group,there were no statistically significant differences between the two groups(P=0.862).We found no statistically significant differences between the two groups in terms of nonunion(P=1.000),delayed union(P=0.757)and malunion(P=0.704).There were no differences noted in the number of the failure of internal fixation between the two groups(P=0.517).When we compare complication rates among the two groups,there were no statistically significant differences found in terms of the surgical site infection(P=1.000).In addition,the superficial surgical site infections rate(P=1.000)and the deep surgical site infections rate(P=0.757)were also not significantly different between the groups.Conclusions: In terms of the treatment of closed tibial pilon fractures,fibula fixation is not routinely necessary and does not result in decreased fracture related complications such as malunion,delayed union,nonunion and implant failure.Fibula fracture fixation should be reserved for cases where it was needed for providing additional stability.