A Retrospective Comparison Of Platelet Indices For Diagnosing Infected Nonunion

Background: Previous studies have been conducted to evaluate the diagnostic values of platelet indices in some infectious diseases. However, the predictive values of platelet indices for infected nonunion have not yet been evaluated. The purpose of this study was to assess the diagnostic performance of platelet indices in infected nonunion.Methods: This study was performed retrospectively on patients who underwent primary fracture nonunion revision surgeries from January 2016 to December 2021. 297 patients with 96 infected nonunion (group A) and 201 aseptic nonunion (group B) who met our inclusion criteria were included. Receiver Operator Characteristic (ROC) curve, sensitivity, and specificity of preoperative clinical parameters were analyzed and compared. Results: The demographic characteristics were similar and had no significant difference between two groups. Compared with group B, the levels of WBC, CRP, ESR, plasma fibrinogen, plasma D-dimer, PC, PCT, and PC/MPV were significantly higher, but the levels of MPV and PDW were significantly lower in group A (p < 0.05). ROC curves showed that PC/MPV and plasma fibrinogen outperformed the other coagulation indicators, with areas under the curve of 0.801 and 0.807, respectively. The multiple tests of ESR, plasma fibrinogen and PC/MPV had good sensitivity and specificity for the diagnosis of infected nonunion, and the diagnostic values of PC/MP was better than ESR and plasma fibrinogen in the subgroup. Conclusions: Our study demonstrates that the diagnostic performance of coagulation indicators, plasma fibrinogen and PC/MPV, are high and they can increase the accuracy of infected nonunion diagnosis.