Local Infiltration Analgesia Following Unicompartmental Knee Arthroplasty

In Group A, 200 mg ropivicaine, 30 mg ketorelac and 0.5 mg epinephrine (total volume 106 ml) are infiltrated by the surgeon into the soft tissues peri-articularly during the operation in the following way: Before inserting the components, 20-30 ml are injected into the posterior capsule and before closure of the wound the rest is injected into the capsule incision, the synovium, the ligament and the subcutaneous tissue After 21 postoperative hours in Group A, 150 mg ropivicaine, 30 mg ketorelac and 0.1 mg epinephrine, total volume 22 ml, are injected intraarticularly via the catheter.

In Group P (placebo) no injections were given intaoperatively. All patients had a tunnelled intra-articular multihole 20-G catheter placed at the end of the operation by the surgeon.After 21 postoperative hours 22 ml of saline was injected intraarticularly via the catheter.