Clinical Research Directory

Inclusion Criteria: * Between 40 and 75 years of age * Patients who are medically cleared and scheduled for unilateral primary total knee replacement * No focal neurologic deficit of the surgical lower extremity * Cognitively intact with the ability to sign informed consent Exclusion Criteria: * Chronic pain syndromes such as fibromyalgia or complex regional pain syndrome * History of long term use of daily opioids (\>1 months) with oral morphine equivalent (OME) \>5mg/day. * Body mass index (BMI) \> 40 kg/m2 * Allergies to medications used in this study such as: fentanyl, hydromorphone, ketorolac, ibuprofen, acetaminophen, local anesthetics, oxycodone, OxyContin, tramadol, ondansetron, droperidol, or dexamethasone, celecoxib * Major systemic medical problems such as: * Severe renal disorder defined as glomerular filtration rate (GFR) \<50 units/m2 * Cardiovascular disorders defined as congestive heart failure (CHF) New York Heart Association (NYHA) class III-IV * Severe hepatic disorder defined as current or past diagnosis of acute/subacute necrosis liver, acute hepatic failure, chronic liver disease, cirrhosis (primary biliary cirrhosis), fatty liver, chronic hepatitis/toxic hepatitis, liver abscess, hepatic coma, hepatorenal syndrome, other disorders of liver. * Impaired cognitive function or inability to understand the study protocol * Contraindication to a regional anesthesia technique (e.g., preexisting neuropathy in the operative extremity, coagulopathy \[platelets \< 100,000, International Normalized Ratio (INR) \>1.5\], refusal, etc.). * Previous contralateral knee replacement managed with regional or periarticular injection * Unable to follow-up at the one year interval at Allegheny Health Network * Pregnancy or breast feeding (women of child-bearing potential, must have a negative pregnancy test)