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.
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
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
100
femoral nerve block (ropivacaine 0.5%, 20 mL) with femoral nerve block infusion 48 h (ropivacaine 0.2%, 5mL/h), placebo local infiltration
single femoral nerve block (ropivacaine 0.5%, 20 mL), placebo femoral nerve block infusion, placebo local infiltration
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)
St. Joseph's Healthcare Hamilton
Hamilton, Ontario, Canada
Sunnybrook Health Sciences Centre
Toronto, Ontario, Canada
Numeric Rating Scale for Pain
Pain at this time is the primary impediment to beginning physiotherapy and achieving discharge criteria
Time frame: 09h00 on postoperative day 2
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
Time frame: Cumulative 4 day consumption
Knee range of motion
Active and passive range of motion - physical outcome measure
Time frame: Measured each postoperative day (4 day maximum) during daily physiotherapy session
Six minute walk test
Validated functional outcome measure after total knee arthoplasty
Time frame: Measured once at the first postoperative visit with the surgeon, 6 weeks postoperative
Timed up and go
Functional outcome measure
Time frame: Measured once on postoperative day 2 during the physiotherapy session
WOMAC
Western Ontario and McMaster University Osteoarthritis Index - functional outcome measure questionnaire
Time frame: Baseline questionnaire given preoperatively, at first postoperative visit (6 weeks), and second postoperative visit (3 months)
LEFS
Lower extremity functional scale - functional outcome questionnaire
Time frame: 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
Time frame: 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
Time frame: From date of randomization until the first postoperative visit at 6 weeks
Inability to ambulate/falls
Time frame: Participants will be followed for the duration of hospital stay, an expected average of 4 days
Nausea
Time frame: 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
Time frame: 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
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.