Perioperative deep venous thrombosis in patients with tibiofibular fracture

Objective To investigate the regularity in and risk factors for perioperative deep venous thrombosis (DVT) and the changes in plasma D-dimer in patients with tibiofibular fracture. Methods A retrospective analysis was done of the 180 patients with tibiofibular fracture who had been treated at Department of Orthopaedics and Trauma, Xi'an Honghui Hospital from September 2014 to February 2018. They were 114 males and 66 females, aged from 16 to 83 years (average, 47.6 years). The levels of plasma D-dimer were detected at admission, one day preoperation, and 1, 3, 5 days postoperation. B-ultrasound examination of both lower extremities was performed before and after surgery. According to the results of B-ultrasound, the patients were divided into a DVT group and a non-DVT group. The 2 groups were compared in the plasma D-dimer levels measured at different time points. DVT risk factors were screened by univariate analysis, and multivariate logistic regression analysis was used to determine independent risk factors. Results Of this cohort, 54 cases (30%) developed DVT and 39 cases (21.7%) did preoperation. Of the 39 cases (mixed DVT in one and distal DVT in 38 ones), DVT disappeared in 14 postoperation. Of the 40 cases (22.2%) of postoperative DVT (proximal DVT in one, mixed DVT in one and distal DVT in 38 ones), 15 developed newly postoperation. Multivariate logistic regression analysis showed that age, time from injury to operation, pre-operative and postoperative D-dimer elevation were independent risk factors for DVT in the patients. The D-dimer levels in the DVT group were significantly higher than in the non-DVT group at one day preoperation, and 1, 3, 5 days postoperation (P<0.05). The area under the receiver operating characteristic curve was 0.704. When the critical value of D-dimer was 1.4 mg/L, its sensitivity for DVT diagnosis was 0.944 and its specificity 0.246 (poor). When the concentration of D-dimer was 4.45 mg/L, its sensitivity for DVT diagnosis was 0.574 and its specificity 0.817 (the highest). Conclusions Perioperative DVT may happen in patients with tibiofibular fracture, mostly at the distal end beyond the popliteal vein. Clinically, patients who are advanced in age, have plasma D-dimer elevation at admission and after operation, and have waited long for operation should be alert to the occurrence of DVT. The plasma D-dimer level with a recommended threshold of 4.45 mg/L may have a certain diagnostic value for patients with tibiofibular fracture. Key words: Tibia; Fibula; Fractures, bone; Deep vein thrombosis; Risk factors; D-dimer