[Risk prediction for deep venous thrombosis after total knee arthroplasty based on modified Caprini risk assessment model:a confirmatory study].

ABSTRACT

OBJECTIVE: To investigate the effectiveness of modified Caprini risk assessment model(Caprini MRAM) in predicting the risk of deep venous thrombosis (DVT) after total knee arthroplasty (TKA). METHODS: A case-control study was used to collect 43 patients with DVT after TKA in lower limb department of Sichuan Orthopedic Hospital from January 2016 to November 2020 in the positive group, and 172 patients without DVT after TKA in the same period according to the 1∶4 ratio between positive and control group were selected in the control group. Caprini MRAM was used to score and grade the risk of DVT. The clinical data, score and risk classification of the two groups were compared. The relationship between the risk of DVT in the patients after TKA and the risk factors in the risk ckassification and assessment of Caprini MRAM was analyzed by multivariate logistic regression model. RESULTS: The average score of caprini in DVT group was significantly higher than that in control group[(8.11±2.91) vs(4.07±2.12), P<0.001];DVT group was mainly at medium and high risk group(66.67%), while the control group was mainly at low risk (77.33%). There was a significant difference between the two groups in risk classification composition (P<0.001). BMI≥30 kg/m2, lower extremity edema (<1 month), severe pulmonary disease (<1 month), acute myocardial infarction (<1 month), bed rest (> 2 h), history of superficial or deep vein or pulmonary embolism and family history of thrombosis were the main risk factors for DVT in patients after TKA(all P<0.05). Preoperative D-dimer elevation (OR=4.380), BMI≥30 kg/m2(OR=2.518), lower extremity edema(<1 month)(OR=7.652), acute myocardial infarction (<1 month) (OR=1.994), bed rest (> 72 h)(OR=3.897), history of superficial or deep vein or pulmonary embolism (OR=13.517) and family history of blood embolism (OR=6.551) were independent risk factors for DVT in patients after TKA (all P<0.05). The risk of DVT was 13.457 and 2.739 times higher in high and moderate risk TKA patients with Caprini MRAM classification, respectively. CONCLUSION: Caprini MRAM can be used to predict the risk of DVT in patients after TKA, especially for patients with high risk.