The primary objective of this clinical study is to evaluate the comparative efficacy of interscalene block (ISB) using plain bupivacaine with adjuvants vs. liposomal bupivacaine on mean postoperative pain levels in patients who have undergone a total shoulder arthroplasty within the first 48 hours. Principal Investigators hypothesize that ISB using plain bupivacaine with adjuvants will provide similar pain relief as ISB using liposomal bupivacaine.
The purpose of this study is to determine whether the use of plain bupivacaine with common adjuvants for interscalene block (ISB) provides non-inferior analgesic results compared to the use of liposomal bupivacaine for ISB, in patients undergoing total shoulder arthroplasty.