Evaluation of Utility of Ultrasound Guided iPACK Block for Knee Extension After Total Knee Arthroplasty.

Study Overview
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Brief Summary
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The purpose of this study is to learn if using an Interspace between the Popliteal Artery and Capsule of the Knee (iPACK) injection technique (also called a nerve block) that numbs the nerves going to the back part of the knee to aid in physical therapy after surgery. The iPACK technique uses a numbing solution (local anesthetics) that is injected behind the knee to reduce pain and to help straighten the knee. This block may affect movement in the leg and make the legs weak, but thing is rare. A few institutions use the iPACK block for patients having total knee replacements, with the hope of providing good pain relief combined with improved mobility after surgery.

Official Title
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Evaluation of Utility of Ultrasound Guided iPACK Block for Knee Extension After Total Knee Arthroplasty.

Conditions
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Knee Osteoarthritis, Primary Total Knee Arthroplasty, Physical Therapy, Pain, Knee Extension

Intervention / Treatment
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* Drug: Ropivacaine
* Procedure: Interspace Between the Popliteal Artery and Capsule of the Knee (iPACK) Block
* Drug: Saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: English speaking Between 18 and 75 years old American Society of Anesthesiologists (ASA) 1-3 patients undergoing primary total knee arthroplasty Exclusion Criteria: ASA 4 or 5 Revision knee arthroplasty Diagnosis of chronic pain Daily chronic opioid use (over 3 months of continuous opioid use) Inability to communicate pain scores or need for analgesia Acute knee dislocation/fracture Infection at the site of block placement Age under 18 years old or greater than 75 years old Pregnant women Intolerance/allergy to local anesthetics Weight <50 kg Suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years. Uncontrolled anxiety, schizophrenia, or other psychiatric disorder that, in the opinion of the investigator, may interfere with study assessments or compliance Current or historical evidence of any clinically significant disease or condition that, in the opinion of the investigator, may increase the risk of surgery or complicate the subject's postoperative course.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: iPACK Block Group<br>A nerve block technique using a numbing medication called ropivacaine. | Drug: Ropivacaine<br>* Local anesthetic (numbing drug)<br>* Other names: Naropin;Procedure: Interspace Between the Popliteal Artery and Capsule of the Knee (iPACK) Block<br>* An ultrasound guided nerve block using a numbing medication called ropivacaine that numbs the nerves to the back of the knee.<br>* Other names: Posterior Capsule;|
| Placebo Comparator: Sham Group<br>The same nerve block technique as above, however using an inactive solution of salt water. | Procedure: Interspace Between the Popliteal Artery and Capsule of the Knee (iPACK) Block<br>* An ultrasound guided nerve block using a numbing medication called ropivacaine that numbs the nerves to the back of the knee.<br>* Other names: Posterior Capsule;Drug: Saline<br>* An ultrasound guided nerve block using a medication that does NOT numb the nerve called saline, or salt water.<br>* Other names: Salt water placebo;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Participants Able to Hyperextend the Knee After Surgery | Ability to hyperextend the knee after surgery | Within 8 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ambulation as Measured by Distance Walked After Surgery |  | Post-operative Day 0 | 
| Pain as Measure by Numerical Rating Scale (NRS) 11 | The 11-point numeric rating scale ranges from 0 (no pain) to 10 (worst pain imaginable). | 24 hours | 
| Cumulative Opioid Consumption | Total amount of opioids used | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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iPACK, Interspace between the Popliteal Artery and Capsule of the Knee, Posterior Capsule block, Nerve Block