A Randomised Controlled Trial Comparing Single Shot Adductor Canal Block With Local Infiltration Analgesia for Postoperative Analgesia After Total Knee Arthroplasty

Study Overview
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Brief Summary
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Total knee arthroplasty or replacement (TKA), a commonly performed surgery for osteoarthritis of the knee, is a painful procedure and requires a multimodal analgesic approach. A method for analgesia is local infiltration analgesia (LIA), where a mixture of drugs is injected around the knee joint. Adductor canal block (ACB) is an alternative regional anaesthesia technique which has been shown to result in minimal thigh weakness. The investigators aim to study if the analgesia provided by ACB is superior to LIA while preserving quadriceps strength.

Official Title
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A Randomised Controlled Trial Comparing Single Shot Adductor Canal Block With Local Infiltration Analgesia for Postoperative Analgesia After Total Knee Arthroplasty

Conditions
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Analgesia in Total Knee Arthroplasty

Intervention / Treatment
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* Procedure: Adductor Canal Block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for primary TKA under single shot spinal anaesthesia, between ages 45-85 years old, American Society of Anesthesiologists (ASA) physical status 1 to 3 and BMI 18-35 kg/m2 Exclusion Criteria: Patients unable to give consent, inability to communicate/ cooperate, patients with regular consumption of strong opioids (morphine, oxycodone) or steroids, allergy to local anaesthetics or any drugs included in the study, patients with lower limb surgery in the preceding year, patients with pre-existing neurological deficits and patients who have contraindications for spinal anaesthesia.

Ages Eligible for Study
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Minimum Age: 45 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Local Infiltration Analgesia<br>The Local Infiltration Analgesia group will receive local infiltration of ropivacaine 150mg, ketorolac 30mg, morphine 10mg, adrenaline 200mcg and vancomycin 500mg in a total volume of 75mls by the surgeon. | |
| Active Comparator: Adductor Canal Block<br>The Adductor Canal Block group of patients will receive intravenous ketorolac 30mg intra-operatively and an adductor canal block at the end of surgery. The block will be performed under real time ultrasound guidance and 30mls of 0.5% ropivacaine (150mg) is injected with a Stimuplex A100, 21G needle. | Procedure: Adductor Canal Block<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Morphine consumption in the first 24 hours | morphine consumption in the first 24 hours (including morphine administered in recovery and via PCA). | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain Scores | Pain scores are recorded at 1, 6, 12, 24 and 48 hours post-operatively, assessed using a visual analog scale (0-100mm) at rest and during 45 degree passive flexion of knee. | 1, 6, 12, 24 hours; up to 48 hours postoperative | 
| Morphine Consumption | The balance usage after primary outcome | At 48 hours | 
| Postoperative Nausea and Vomiting | Presence/absence of nausea and vomiting, and total number of episodes of vomiting | Up to 48 hours | 
| Sedation Scores |  | Up to 48 hours | 
| Quadriceps Strength |  | at 24 and 48 hours |