Extended Prophylaxis Comparing low molecular weight heparin (LMWH) to Aspirin in Total hip arthroplasty

Current hypothesis as of 05/12/2007:. Extending the duration of anti-thrombotic prophylaxis with aspirin by 28 days following a ten day course of Low Molecular Weight Heparin (LMWH) will be as effective at reducing the rate of symptomatic venous thromboembolic complications and will be safe and more cost-effective than extending prophylaxis by 28 days with LMWH in a group of patients undergoing total hip arthroplasty.. Previous hypothesis:. Extending the duration of anti-thrombotic prophylaxis with aspirin by 28 days following a minimum seven day course of Low Molecular Weight Heparin (LMWH) will be as effective at reducing the rate of symptomatic venous thromboembolic complications and will be safe and more cost-effective than extending prophylaxis by 28 days with LMWH in a group of patients undergoing total hip arthroplasty.. Please note that this record has been updated on the 5th December 2007 due to changes made to this protocol by the suggestion of the Research Ethics Board (REB). All changes were made prior to the recruitment of the first study participant and will be entered in this record under the date 05/12/2007.