Local Injection of Local Anesthetic 24 Hours After Knee Replacement Surgery May Decrease Pain for Several More Hours

The purpose of this study is to determine if an additional injection of local anesthetic immediately prior to removal of the local anesthetic infiltration catheter on postoperative day one is effective in increasing pain reduction, patient satisfaction or outcome measures following total knee replacement (TKR). It is hypothesized that an additional injection of 30ml of .5% bupivacaine solution immediately before infiltration catheter removal will provide pain reduction, patient satisfaction and outcome measures equal or superior to catheter removal with no additional injection. Patients who are undergoing unilateral total knee replacement (TKR) and choose to participate will be randomly assigned to a treatment group.Patients in group one (treatment group) will receive a 30ml dose of .5% bupivacaine solution injected into the local anesthetic infiltration catheter immediately prior to its removal on postoperative day one. Patients in group two (control group) will receive no additional medication during local anesthetic infiltration catheter removal.