The value of D-dimer in the detection of early deep-vein thrombosis after total knee arthroplasty in Asian patients: a cohort study

BACKGROUND AND PURPOSE: The relationship of D-dimer and deep-vein thrombosis (DVT) after total knee arthroplasty (TKA) remains controversial. The purpose of this study was to assess the value of D-dimer in the detection of early DVT after TKA. METHODS: The measurements of plasma D-dimer level were obtained preoperatively and at day 7 postoperatively in 78 patients undergoing TKA. Ascending venography was performed in 7 to 10 days after surgery. The plasma D-dimer levels were correlated statistically with the venographic DVT. RESULTS: Venographic DVT was identified in 40% of patients. High plasma D-dimer level >2.0 μg/ml was found in 68% of patients with DVT and 45% without DVT (P < 0.05). Therefore, high D-dimer level greater than 2.0 μg/ml showed 68% sensitivity, 55% specificity, 60% accuracy, 50% positive predictive rate and 72% negative predictive rate in the detection of early DVT after TKA. CONCLUSION: High plasma D-dimer level is a moderately sensitive, but less specific marker in the detection of early of DVT after TKA. Measurement of serum D-dimer alone is not accurate enough to detect DVT after TKA. Venography is recommended in patients with elevated D-dimer and clinically suspected but asymptomatic DVT after TKA.