More and more Americans are benefiting from knee joint replacements for severe arthritis. Problems sometimes occur after the operation to reduce knee motion. Deep vein thrombosis (DVT) or blood clots is one of these problems.
DVTs can be prevented in patients receiving a knee joint. Drugs, leg pumps, and exercise are used in this effort. Without these measures, 50 to 70 percent of patients having this operation will develop DVT. With preventive steps, the number of patients affected drops to 30 percent or less.
There are several drugs that can be used to prevent blood clotting. Aspirin is a commonly known choice. Others include enoxaparin and warfarin. This study looked at two drugs used to prevent blood clots and how they affected knee range of motion after knee replacement surgery.
One group of patients received aspirin after the operation. The second group got enoxaparin. Both are blood thinners with advantages and disadvantages. Enoxaparin can cause major and minor cases of bleeding, and there may be more wound drainage and leg swelling with this drug. Aspirin can cause bleeding ulcers.
Patients receiving aspirin regained knee motion faster than those on enoxaparin. With aspirin, there was less pain and faster recovery. These results are only present in the short-term. Fifteen months after the operation, both groups had the same range of motion.
The authors emphasize that the type of drug used to prevent blood clots is important in knee joint replacements. When aspirin is used, patients have less pain and less swelling, resulting in more motion. Early motion is a big measure of success after knee joint replacement surgery. Aspirin appears to give this edge for patients receiving a new knee joint.