Predictive Analysis Of DVT After Unilateral TKA And UKA In Early D-dimer Changes

ObjectiveTo evaluate the prediction value of early D-dimer variation rules in the occurrence of deep venous thrombosis(DVT)after Total knee arthroplasty(TKA)and Unicompartmental knee arthroplasty(UKA),and to guide clinical treatment.MethodsA follow-up and retrospective investigation was conducted on 74 patients who were diagnosed with unilateral knee osteoarthritis in the Department of Orthopedics of Hebei People’s Hospital from September 2018 to November 2020,including 16 males and 58 females aged 50-86 years old.Demographic data of subjects including age,gender and body mass index were collected and collated.According to the patient’s surgical method,the patients were divided into total knee arthroplasty(TKA)group(n=38)and unicompartmental knee arthroplasty(UKA)group(n=36).Each of them was divided into two subgroups according to the results of deep vein and intermuscular vein Doppler color ultrasonography of both lower limbs within 7 days after operation.The total knee arthroplasty(TKA)group was divided into non-thrombotic group(TKA-1)(28 cases)and thrombosis group(TKA-2)(10 cases)(all asymptomatic thrombosis patients).The knee unicondylar arthroplasty(UKA)group was divided into non-thrombotic group(UKA-1)(27 cases)and thrombus group(UKA-2)(9 cases)(all asymptomatic thrombosis patients).The D-dimer values and Doppler color ultrasonography results of lower extremity deep vein and intermuscular vein were collected before and 1,2,5 and 7 days after operation,and the effects of D-dimer values on the occurrence of postoperative DVT were statistically analyzed.ResultsComparing the TKA-1 and TKA-2 groups,peaks appeared on the 1st and 5th day after surgery.In the TKA-2 group,D-dimer had its first peak on the first day after surgery,with a median of 5.03 mg/L and an interquartile range(4.22-5.78)mg/L.It decreased at 2 days and reached the second peak at 5 days after surgery,with a median of 2.87 mg/L and an interquartile range of(2.43-2.97)mg/L.Compared with TKA-1group,the D-dimers were significantly increased on 1d,2d,5d,7d after the operation in the TKA-2 group,and the difference was statistically significant and the test P value was less than 0.05.The ROC curve was drawn with the D-dimer values measured at the corresponding time points in the TKA-1 and TKA-2 groups,and the cut-off point on the second day after surgery was 1.010 mg/L,and its sensitivity and specificity were70.00% and 92.86% respectively;the cut-off value on the fifth day after surgery was2.330 mg/L,and its sensitivity and specificity were 90.00 % and 82.14%,The area under the ROC curve was 0.904 on the fifth day after operation.Comparing the UKA-1 and UKA-2 groups,peaks appeared on the 1st and 5th days after surgery.In the UKA-2 group,D-dimer had its first peak on the first day after surgery,with a median of 3.97 mg/L and an interquartile range(3.04-5.35)mg/L.Ddimer decreased at 2 days and reached the second peak at 5 days after surgery,with a median of 2.97 mg/L and an interquartile range of(2.10-3.43)mg/L.Compared with UKA-1 group,the D-dimers were significantly increased on 1d,2d,5d,7d after the operation in the UKA-2 group,and the difference was statistically significant and the test P value was less than 0.05.The ROC curve was drawn with the D-dimer values measured at the corresponding time points in the UKA-1 group and UKA-2 group,and the cut-off value on the fifth day after surgery was 1.920 mg/L,and its sensitivity and specificity were 88.89% and 85.19%,the cut-off value was 1.370mg/L on the 7th day after the operation,the sensitivity and specificity were 55.56% and 96.30% respectively.The area under the ROC curve was 0.928 on the fifth day after operation.Conclusion1.The changes of D-dimer on the second day after the TKA have certain predictive value for deep vein thrombosis.The changes of D-dimer on the fifth day after TKA have certain predictive value for the indication of deep vein thrombosis.2.The changes of D-dimer on the fifth day after the UKA have certain predictive value for the indication of deep vein thrombosis.The changes of D-dimer on the 7th day after UKA have certain predictive value for the exclusion of DVT.3.The early D-dimer changes after TKA and UKA are bimodal changes,which has important clinical reference value for the early prediction of postoperative DVT and can guide the clinical treatment.