A study on risk factors for deep venous thrombosis after knee arthroplasty

ZHU Meng-hai; LI Shi-fei; LONG An-hua; YAO Qi

doi:10.3969/j.issn.2095-252X.2016.10.003

Abstract：Objective To explore the risk factors for deep venous thrombosis ( DVT ) after knee arthroplasty and the diagnosis value of D-dimer for DVT.Methods A retrospective study was performed on 136 patients ( male 40, female 96 ) undergoing knee replacement surgery between January 2013 and December 2015, whose average age was ( 70.7 ± 10.1 ) years. Ultrasonography was used to assess the DVT occurrence in the lower limbs of the patients. Logistic regression was used to identify the association of DVT and the variables including the gender, age, preoperative braking time, duration of surgery, bed rest time after the surgery, plasma D-dimer concentration, ifbrinogen ( FIB ) concentration and chronic illness.Results The plasma D-dimer level was 1.82 mg / L ( range: 1.53 - 4.53 mg / L ) in the DVT group, which was 0.45 mg / L ( range: 0.21 - 1.22 mg / L ) in the control group. And the differences were statistically signiifcant (P < 0.05 ). Logistic regression analysis showed that plasma D-dimer level, duration of surgery and chronic illness were risk factors for the development of DVT, but further studies should be performed on the association of DVT and the age, gender, preoperative braking time, bed rest time after the surgery and FIB concentration. Receiver operating characteristic ( ROC ) curves showed when the cut-off point of plasma D-dimer was 1.5 mg / L, the sensitivity was 88.9% and the speciifty was 84.7% in the prediction of DVT.Conclusions Duration of surgery and chronic illness are signiifcant risk factors for the development of DVT. When the plasma D-dimer is more than 1.5 mg / L, a higher occurrence rate of DVT should be noticed, and regular review of leg veins and clinical intervention may be necessary.