Patient case (clinical description): A 47-year-old woman comes to the office complaining of pain in the calf and knee when she bends down. The pain limits her activity. Her medical history is significant for osteoarthritis, for which she uses nonsteroidal anti-inflammatory drugs (NSAIDs) for the past two years. She is living with her husband and has 3 children. She doesn't smoke but drinks alcohol occasionally. Her vital signs are normal. On physical examination, there is a small effusion in the right knee. The effusion grew a little larger and she developed a tender swelling in the popliteal fossa and calf. Both the pain and swelling worsened as she bent and straightened her knee.

Patient's own account: I'm a 47-year-old woman, married with 3 kids. I don't smoke and I drink occasionally. I went to the doctor because of pain in my calf and knee when I was bending down. This has been limiting my daily activities. I have been diagnosed with osteoarthritis for which I have taken anti-inflammatory drugs for the past 2 years. The doctor saw a small fluid buildup in my right knee. This buildup became a bit bigger and I have a swollen calf. The pain is worse when I bend and straighten my knee.

Clinical trial: Peripheral Nerve Blocks vs Periarticular Local Anesthetic Injection for Total Knee Arthroplasty (TKA)

Eligibility criteria:
Inclusion Criteria:

          1. Adult patients with an American Society of Anesthesiologists (ASA) physiological
             status I-III

          2. Patients presenting for unilateral primary total knee replacement.

          3. No focal neurologic deficit of the surgical lower extremity.

          4. Cognitively intact with the ability to sign informed consent

        Exclusion Criteria:

          1. Chronic pain syndromes such as fibromyalgia or complex regional pain syndrome

          2. History of long term use of daily opioids (>1 months) with oral morphine equivalent
             (OME) >5mg/day.

          3. Body mass index (BMI) > 40 kg/m2

          4. Allergies to medications used in this study such as: fentanyl, hydromorphone,
             ketorolac, ibuprofen, acetaminophen, local anesthetics, oxycodone, OxyContin,
             tramadol, ondansetron, droperidol, or dexamethasone, celecoxib

          5. 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.

          6. Impaired cognitive function or inability to understand the study protocol

          7. 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.).

          8. Previous contralateral knee replacement managed with regional or periarticular
             injection

          9. Unable to follow-up at the 3 month interval at Mayo Clinic in Rochester, Minnesota

         10. Pregnancy or breast feeding (women of child-bearing potential, must have a negative
             pregnancy test)
No condition on gender to be admitted to the trial.
Accepts Healthy Volunteers
Subject must be at least 18 Years old.


Eligibility (NLI label): Entailment