Clinical Research Directory

Inclusion Criteria: * American Society of Anesthesiologists status I, II and III, elective, primary, unilateral TKA planned for spinal anesthesia with plain 0.5% bupivacaine. Exclusion Criteria: * Refusal of consent * Pregnancy * Conditions making the patient unable to fill out questionnaire online, through email or over the phone including with cognitive dysfunction, psychiatric disorder, or non-English speaking patients, or lack of internet access which would prevent post discharge follow-up electronically * Coagulopathy * Allergy to or for any other reasons cannot use Acetaminophen, Celebrex, local anesthetic bupivacaine, DEX, MPA or LB * Patients on any amounts of opioids within one month of the surgery date, any substance abuse such as regular marijuana user (more frequent than once per month) * Insulin dependent or uncontrolled diabetes defined as, day of surgery finger stick glucose \>200mg/dl, or HbA1C \> 8.0% * Peripheral Nerve Block site or systemic infection * Immune compromise (e.g., HIV, chronic glucocorticoid use) * Severe pre-existing neuropathy * TKA for indications other than osteoarthritis such as post-traumatic injury or rheumatoid arthritis, history of surgery in the ipsilateral knee joint, revision TKA or bilateral TKA * Severe hepatic or renal dysfunction (GFR \<50 ml/min) * Actual body weight \<60 kg * Patients with active or latent peptic ulcers, diverticulitis, fresh intestinal anastomoses, and non-specific ulcerative colitis