Multivariable Logistic Regression Analysis Of Factors Related To Efficacy After Surgical Treatment Of Ankle Fractures

Objective: To explore factors related to efficacy of surgical operation of ankle fracture,sum up the experience and provide the reference for clinical physicians in treatment of ankle fracture.Method: A total of 123 patients of ankle fracture were treated by surgical Operation in the department of orthopaedics of Second Hospital of Lanzhou University between June 2012 and March 2016,and their data were retrospectively analyzed.According to follow ups and clinical information,we selected possible affecting factors as following,(1)General data and past medical history such as: gender,age,complicated with diabetes,have a smoke;(2)Condition of injury: the cause of injury,type of fracture(AO-Danish-Weber),open injury,swelling of injury limb,injury of blood vessel,injury of nerve;(3)Preoperative preparation: CT of ankle joint,Calcaneal traction,time before operation;(4)Operative treatment: surgical methods;(5)Postoperative recovery and complications: taking calcium supplements after surgery,partial weight beating time and the wound healing.The selected factors were grouped and assigned,and then single factors Logistic regression was performed.For dichotomous data univariate Logistic regression equal to Chi-squared test.After unrelated factors were excluded,multivariable Logistic regression analysis was performed.Result: 123 patients were followed up for 6~24 months after surgery,average of(15.19±6.12)months.According to AO-Danish-Weber classification,there were 34 patients of type A,45 patients of type B and 44 patients of type C.According to Mazur(1979)assessment criteria,ankle function was excellent in 30 cases,good in 47 cases,fair in 29 cases,and poor in 17 cases at the final follow-up,the excellent and good rate was 62.6%,and after univariate Logistic regression,we found age,the cause of injury,type of fracture(AO-Danish-Weber),Calcaneal traction,CT of ankle joint,open injury and surgical methods had significant differences,with P values,OR values and 95%CI were respectively: 0.001,2.686(1.575~4.579);<0.001,3.862(2.245~6.646);<0.001,4.871(2.606~9.103);0.010,3.000(1.306~6.893);0.004,3.052(1.427~6.528);0.002,0.262(0.112~0.614);<0.001,3.974(2.065~7.649).After multivariate Logistic regression analysis showed age,the cause of injury,type of fracture(AO-Danish-Weber),Calcaneal traction,CT of ankle joint,open injury and surgical methods had significant differences.With P values,OR values and 95%CI were respectively: 0.014,2.688(1.225~5.898);0.004,3.334(1.453~7.651);0.025,3.048(1.148~8.092);0.027,4.099(1.174~14.313);0.039,3.499(1.064~11.509);0.023,0.176(0.039~0.784);0.049,2.798(1.003~7.809).Conclusion: age,the cause of injury,type of fracture(AO-Danish-Weber),Calcaneal traction,CT of ankle joint,open injury and surgical methods were main prognostic factors affecting postoperative function of the ankle joint.Accurate diagnosis of the fracture type,completing preoperative examination to precisely found fracture fragments with or without ligament damage,preoperative preparation such as calcaneal traction and reduce the swelling of the limb could improve the function of ankle joint and prevent the occurrence of traumatic arthritis as possible.