Liposomal Bupivacaine Versus Interscalene Nerve Block

The aim of this study is to compare two different pain management interventions in patients undergoing reverse total shoulder arthroplasty. The two interventions are 1) pre-operative interscalene nerve block and 2) intraoperative injection of liposomal bupivacaine (Exparel, Pacira Pharmaceuticals, Parsippany NJ). Specifically, the primary aims of this study are to compare these two interventions on the following: post-operative opioid consumption, pain scores, and patient satisfaction. Additionally, the investigators want to determine if psychological factors, catastrophizing and resilience, are associated with post-operative pain control and satisfaction. The investigators' hypothesis is that the two interventions will have similar pain control efficacy and that the liposomal bupivacaine group will experience faster post-operative recovery, earlier discharge, and improved satisfaction. The investigators also expect patient catastrophizing and resilience to significantly predict the degree of post-operative pain and level of patient satisfaction.