The outcome of muscular vein thrombosis after knee and hip arthroplasty

Abstract

Objective To observe the outcome of muscular vein thrombosis after joint arthroplasty and to analyze potential factors that could affect the result. Methods From January 2015 to December 2015, a total of 47 fresh muscular vein thrombosis diagnosed by ultrasound were collected during hospitalization. There were 6 male and 41 female with the average age of 68.3±7.7 years old (46-92 years old). Among them, 36 patients underwent knee arthroplasty, while 11 accepted hip arthroplasty. Sonography was used to evaluate the resolution of muscular vein thrombosis at the time point of 6 weeks and 3 months postoperatively and the results were compared between the two time points. Multivariable analysis was performed to evaluate the relationship between the resolution of DVT 3 months postoperatively and risk factors including age (>65/≤65 years old), Body Mass Index (>25/≤25 kg/m2), gender (male/female), type of surgery (knee/hip), maximum length of thrombosis (>5/≤5 cm), maximum diameter (>1/≤1 cm), duration of anticoagulation therapy (extended anticoagulation therapy after discharge/anticoagulation therapy during hospitalization), time of diagnosis with DVT (before surgery/within 3 days postoperatively/postoperative day 4 to hospital discharge). Results Nine cases were diagnosed preoperatively, 27 cases were found between postoperative day 1 and 3, and 11 cases were found between day 4 and discharge. At 6 weeks postoperatively, 44 cases of muscular vein thrombosis were found resolving with 19 cases (40.4%) thoroughly resolvedand 25 cases (53.2%) partly resolved, only 1 case (2.1%) progressed into the popliteal veins, 2 cases (4.3%) had no change on the size. At the follow up of 3 months, 45 cases were found resolving with 35 cases (74.5%) through resolved and 10 cases (21.3%) partly resolved, no case progressed into proximal veins, 2 cases (4.3%) had no change on the size. There was significant difference in thrombosis recanalization between the two time points (χ2= 8.797, P=0.003). The maximum diameter of thrombosis showed a significant effect on the lysis on 3 months postoperatively (χ2= 12.231, P=0.000). There was no significant difference between other potential factors and the outcome at 3 months postoperatively. Conclusion Most of fresh muscular vein thrombosis could realize thrombolysis within 3 months after knee and hip arthroplasty. The diameter of thrombosis has a significant effect on the natural course of muscular vein thrombosis. DVTs with diameter larger than 1 cm are difficult to be resolved thoroughly. Key words: Arthroplasty, replacement; Perioperative period; Venous thrombosis; Ultrasonography; Thrombolytic therapy