Please select the eligibility criteria that correspond to the clinical trial below.
Title: Effects of Catheter Location on Postoperative Analgesia for Continuous Adductor Canal and Popliteal-Sciatic Nerve Blocks
Brief Summary: Currently, continuous adductor canal and popliteal-sciatic nerve blocks are used commonly for lower extremity post-operative pain control, specifically for total knee arthroplasty and foot/ankle surgery, respectively. A perineural catheter used to infuse local anesthetic for postoperative analgesia may be placed at various locations along the target nerves. Investigations of single-injection peripheral nerve blocks suggest that the onset of the block might be faster with one location over the other; but, the success rates are equivalent. However, remaining unknown is whether there is an optimal location to place a perineural catheter as part of a continuous peripheral nerve block.


Options:
A: Inclusion Criteria:

* Revision Knee Arthroplasty in general anaesthesia
* American society of anesthesiologists (ASA) 1-3
* BMI 18-40
* Written informed consent

Exclusion Criteria:

* Can not cooperate to the exam
* Do not speak or understand Danish
* Drug allergy
* Alcohol or drug abuse
B: Inclusion Criteria:

* ASA 1-3
* BMI \> 18 og \< 40
* total knee arthroplasty in spinal anesthesia

Exclusion Criteria:

* Can not cooperate to the exam
* Do not speak or understand Danish
* Drug allergy
* Alcohol or drug abuse
* Daily consumption of strong opioids
* Rheumatoid arthritis
* Intake of glucocorticoids
* Effect of spinal anesthesia stopped prior to performing the regional block
C: Inclusion Criteria:

1. undergoing surgery with an adductor canal or popliteal-sciatic perineural catheter for postoperative analgesia following primary tri-compartment knee arthroplasty or foot/ankle surgery;
2. anticipated to have at least moderate pain following surgery \[NRS\>3\]; and,
3. age 18 years or older.

Exclusion Criteria:

1. pregnancy (a urine pregnancy test is standard at UCSD for female patients prior to menopause who are sexually active with the opposite sex within the previous year);
2. inability to communicate with the investigators and hospital staff;
3. clinical neuropathy in the surgical extremity;
4. chronic high-dose opioid use (defined as daily use for more than 4 weeks prior to surgery of at least the equivalent of 20 mg oxycodone);
5. BMI \> 40 kg/m2;
6. allergy to study medications (lidocaine, ropivicaine);
7. known renal insufficiency; or,
8. incarceration.
D: Inclusion Criteria:

* Subject is 40-80 years of age and skeletally mature
* Subject BMI is \< 40
* Subject has been selected by the surgeon for TKA.
* Subject is taking less than 30 mg of Morphine per day.
* Subject is willing and able to sign a written consent form
* The subject has the mental capacity and the willingness to comply with the specified follow-up evaluations, and can be contacted by telephone by the site personnel.
* The subject is not pregnant, does not intend to become pregnant and has a significant other mirroring her intentions.

Exclusion Criteria:

* Subject is not neurologically intact (sensory, motor, and reflex deficit)
* Subject has pain in the limb scheduled for surgery that is out of proportion of expected pain usual for this pathology
* Subject scheduled for simultaneous bilateral knee replacement
* Subject has a history of any invasive malignancy (except non-melanoma skin cancer), unless treated with curative intent and with no clinical signs or symptoms of the malignancy for 5 years
* Subject with prior reconstructive knee surgery on the operated limb
* Subject with primary bone tumor in the knee area
* Subject anticipates having a lower extremity surgery other than the investigational surgery during the course of the study
* Subject has a history of substance abuse
* Subject is currently involved in another study or have received investigational product or treatment within the last 30 days
* Subject is pregnant or planning on becoming pregnant during the study period
* Subject is accepting workers' compensation

Answer: C