Postoperative Pain Control Results Using Periarticular Versus Intra-capsular Injection of Bupivacaine Liposome Injectable Suspension in Total Knee Arthroplasty

The purpose of this study is to determine quantitative and qualitative differences in post-operative pain relief for patients undergoing primary total knee arthroplasty (TKA) who receive administration of a newly approved, long acting local anesthetic branded as ExparelTM (bupivacaine liposome injectable suspension) introduced by one of two different administration methods. Group 1 would receive a predetermined and standardized dose of ExparelTM introduced directly into the joint capsule at the conclusion of the surgery, effectively bathing the joint in anesthetic solution. Group 2 would receive the same predetermined and standardized dose of ExparelTM as a local infiltration anesthetic (LIA) by injecting it into the periarticular tissues in nine (9) standard sites at the conclusion of the surgery.