Optimizing Pain and Rehabilitation After Knee Arthroplasty

Study Overview
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Brief Summary
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The aim of this study is to determine the best method of pain control that will help with rehabilitation after total knee arthroplasty (TKA). Currently, the best method for pain control after TKA appears to be continuous femoral nerve block (FNB) where a small tube is placed beside the nerve that provides sensation to a large part of the knee and local anesthetic infused after surgery causing numbness to the surgical site. A single injection method also exists and may provide similar benefits. Both methods require training and can result in side effects such as temporary weakness (while the local anesthetic is still working) that can inhibit rehabilitation. A newer method injecting local anesthetic into the joint after surgery (Local Infiltration Analgesia (LIA)) is becoming common, does not cause weakness and can be done quickly at the end of surgery. It is unknown if the pain control provided by LIA is as good as that of FNB. This study will compare the femoral nerve block, continuous femoral nerve block and LIA technique to determine which provides better pain relief after TKA.

Detailed Description
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This will be a prospective, randomized, double blind study. Patients will be randomized using a computer-generated sequence to one of three groups: Group 1: Continuous femoral nerve block group (cFNB) Group 2: Single injection femoral nerve block group (sFNB) Group 3: Local infiltration analgesia group (LIA) Inclusion criteria: Patients between the ages of 18 and 85 having primary tri-compartmental total knee arthroplasty. Exclusion criteria: Allergy, intolerance, or contraindication to any study medication (see below), inability to walk independently prior to TKA, inability to comprehend French or English, use of major tranquilizers, ASA 4 or 5, BMI > 40, opioid tolerance (opioid consumption > 30mg oral morphine or equivalent per day), pregnancy

Official Title
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Optimizing Pain and Rehabilitation After Knee Arthroplasty - Randomized, Blinded Clinical Trial Comparing Continuous Femoral Nerve Block Versus Single Injection Femoral Nerve Block Versus Local Infiltration Analgesia

Conditions
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Total Knee Arthroplasty

Intervention / Treatment
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* Other: continuous FNB
* Other: single femoral nerve block
* Other: local infiltration analgesia


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults undergoing primary, tri-compartmental knee arthroplasty Exclusion Criteria: Allergy, intolerance, or contraindication to any study medication Inability to walk independently prior to TKA Inability to comprehend French or English Use of major tranquilizers ASA 4 or 5 BMI > 40 Opioid tolerance (opioid consumption > 30mg oral morphine or equivalent per day) Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: continuous FNB<br>Bolus femoral nerve block (ropivacaine 0.5% 20 mL), continuous infusion 48 hours (ropivacaine 0.2%, 5 mL/h), placebo local infiltration | Other: continuous FNB<br>* femoral nerve block (ropivacaine 0.5%, 20 mL) with femoral nerve block infusion 48 h (ropivacaine 0.2%, 5mL/h), placebo local infiltration<br>|
| Active Comparator: single FNB<br>femoral nerve block (ropivacaine 0.5% 20 mL), placebo femoral nerve block infusion, placebo local infiltration | Other: single femoral nerve block<br>* single femoral nerve block (ropivacaine 0.5%, 20 mL), placebo femoral nerve block infusion, placebo local infiltration<br>|
| Active Comparator: LIA<br>placebo fascia iliac block, placebo fascia iliaca infusion, local infiltration analgesia | Other: local infiltration analgesia<br>* placebo fascia iliac block, placebo fascia iliaca infusion, local infiltration analgesia (tricompartmental injection of 150 mL ropivacaine 0.2%, ketorolac 30 mg, epinephrine 10 microg/mL)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numeric Rating Scale for Pain | Pain at this time is the primary impediment to beginning physiotherapy and achieving discharge criteria | 09h00 on postoperative day 2 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opioid consumption | Opioid consumption is a surrogate outcome for pain. A reduction in opioid consumption also confers benefits of reduced side effects - nausea, dizziness, sedation, respiratory depression | Cumulative 4 day consumption | 
| Knee range of motion | Active and passive range of motion - physical outcome measure | Measured each postoperative day (4 day maximum) during daily physiotherapy session | 
| Six minute walk test | Validated functional outcome measure after total knee arthoplasty | Measured once at the first postoperative visit with the surgeon, 6 weeks postoperative | 
| Timed up and go | Functional outcome measure | Measured once on postoperative day 2 during the physiotherapy session | 
| WOMAC | Western Ontario and McMaster University Osteoarthritis Index - functional outcome measure questionnaire | Baseline questionnaire given preoperatively, at first postoperative visit (6 weeks), and second postoperative visit (3 months) | 
| LEFS | Lower extremity functional scale - functional outcome questionnaire | Baseline questionnaire given preoperatively, at first postoperative visit (6 weeks), and second postoperative visit (3 months) | 
| Incidence of motor block | weakness in quadriceps from femoral nerve block can delay physiotherapy and cause falls | Participants will be followed for the duration of hospital stay, an expected average of 4 days | 
| Complications of femoral nerve block, local infiltration analgesia | hematoma, infection, persistent neurological deficit 6 weeks postoperatively | From date of randomization until the first postoperative visit at 6 weeks | 
| Inability to ambulate/falls |  | Participants will be followed for the duration of hospital stay, an expected average of 4 days | 
| Nausea |  | Participants will be followed for the duration of hospital stay, an expected average of 4 days | 
| NRS for pain | Assessing worst pain during physiotherapy, later dates to assess for the incidence of chronic pain | The highest NRS will be assessed daily during the patient's physiotherapy session, as well as the highest NRS achieved at 2 weeks, 6 weeks, and 3 months postoperatively |