Post-operative pain remains one of the patient's greatest concerns after Total Knee Arthroplasty (TKA). Insufficient pain control can delay mobilization and inhibit rehabilitation efforts. Multimodal analgesia, including peripheral nerve block, is recommended for pain relief, and reaching an effective level of pain management, while minimizing opioid side effects, is vital to a patient's recovery and satisfaction of care delivered. The ON-Q pain relief system continually infuses local analgesia for effective pain relief.