Liposomal Bupivacaine vs Adductor Canal Block in Total Knee Arthroplasty

Inclusion Criteria: * Male or non-pregnant female between the ages of 18-65 * Patients willing and able to sign the informed consent * Patients able to comply with follow-up requirements including self-evaluations * Patients requiring a primary total knee replacement * Patients with a diagnosis of osteoarthritis, traumatic arthritis, or avascular necrosis Exclusion Criteria: * Revision total knee arthroplasty * Bilateral total knee arthroplasty * Patients with inflammatory arthritis * Patients with a body mass index (BMI) \> 40 * Allergy to ropivacaine, bupivacaine, or other local anesthetic agents * Current use of opioid drugs * Patients with a history of total or unicompartmental reconstruction of the affected joint * Patients that have had a high tibial osteotomy or femoral osteotomy * Patients with neuromuscular or neurosensory deficiency, which would limit the ability to assess pain levels * Patients with a systemic or metabolic disorder leading to progressive bone deterioration * Patients that are immunologically compromised, or receiving chronic steroids (\>30 days), excluding inhalers * Patients' bone stock is compromised by disease or infection, which cannot provide adequate support and/or fixation to the prosthesis * Patients with knee fusion to the affected joint * Patients with an active or suspected latent infection in or about the knee joint * Patients that are prisoners