Pre-operative pain will be assessed using the NPRS-11 Standard shoulder arthroplasty is performed. A total injection volume of 100 cc will be comprised of 60 ml of 0.9% normal saline+ 20ml 0.5% bupivacaine + 20ml EXPAREL(liposomal bupivacaine 266mg) will be injected into the deep soft tissue using an 18 or 20 gauge needle prior to or after prosthesis insertion.