Comparison of Two Periarticular Injection Medications for Adjunctive Pain Management Following Total Knee Arthroplasty (TKA)

Exclusion Criteria

• •American Society of Anesthesiologist (ASA) score of 4 or higher
• •Hepatic disease (contraindication for acetaminophen)
• •Renal disease (contraindication for NSAIDs)
• •Any contraindication for oxycodone, ketorolac, epinephrine, pregabalin, gabapentin, hydromorphone, Tramadol, morphine or other narcotics that are considered as part of routine postoperative pain control protocol
• •Fibromyalgia
• •Any contraindication for intrathecal opioid injection
• •History of substance abuse during the last 2 years
• •History of allergy to amide compounds
• •Current consumption of monoaminoxidase (MAO) inhibitors and tricyclic antidepressant (TCA) medications
• •Allergy to metabisulfite compounds
• •Chronic use of opioid medications in the month prior to surgery (leads to opioid tolerance and/or opioid-induced hyperalgesia)
• •Body weight\<50 Kg, BMI\>40 Kg/m2
• •History of hypotension
• •Patients with any surgery related complication in the first 4-6 weeks following TKA, such as infection or mechanical failure