This interview explores a randomized trial comparing periarticular, intra-articular, and combined injections for pain control after total knee arthroplasty. The investigators found that periarticular injection alone produced the lowest early pain, reduced morphine use, and improved early range of motion, likely because analgesic reaches key capsular and ligamentous pain receptors more directly. Although longer-term outcomes equalized, the early advantages led the team to change practice, shortening hospital stays and improving early mobility.