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Location of Injection of Local Anesthetics in the Adductor Canal Block

Not Applicable
Completed
Conditions
Anesthesia
Adductor Canal Block
Interventions
Registration Number
NCT02554864
Lead Sponsor
Women's College Hospital
Brief Summary

The adductor canal block (ACB) is the standard of care for analgesia after Anterior Cruciate Ligament (ACL) repair. ACB is performed by injecting local anesthetic (freezing) in the subsartorial canal in the thigh which is about 7-10cm long. Preliminary evidence suggests that different injection sites within the canal may produce different degrees of analgesia and quadriceps motor block. This trial seeks to determine the effects of various ACB injection sites on postoperative analgesia and motor power following ACL repair.

Detailed Description

Adductor canal block (ACB) is replacing femoral nerve block (FNB) as the peripheral nerve block of choice for knee surgery. The ACB aims to inject local anesthetics (LA) within the neurovascular sheath in the subsartorial adductor canal around the femoral nerve. The point where the sartorius muscle crosses over the femoral artery is generally the accepted site for performing ACB. Clinically, injecting LA in the adductor canal blocks the sensory innervation of the knee and thus offers pain relief that is similar to FNB while conserving motor power around the knee. While these benefits are desirable, the exact location for performing ACB that ensures these benefits, remains debatable. The subsartorial adductor canal itself is 7-10cm long and the anatomical location of the sensory and motor nerves that innervate the knee and its surrounding muscles in this canal may vary. This randomized controlled trial is designed to identify and refine the ACB technique by clinically determining the effects of various ACB injection locations on postoperative analgesia and quadriceps motor power following ACL repair.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
108
Inclusion Criteria
  • Patients booked for anterior cruciate ligament surgery under general anesthesia
  • English speaking
  • BMI <38 kg/m2
Exclusion Criteria
  • Refusal or inability to provide informed consent
  • Allergy to local anesthetics
  • Contraindication to regional anesthesia including coagulopathy or bleeding - diathesis
  • Infection
  • Nerve Injury at the site of the nerve block
  • Malignancy at the site of the nerve block
  • History of drug and/or alcohol dependence
  • History of long term opioid intake or chronic pain disorder
  • History of pre-existing neuropathy in the operative leg
  • History of significant psychiatric conditions that may affect patient assessment
  • Inability to understand the informed consent and demands of the study
  • Allergy to any of the components of multi-modal analgesic regimen
  • Revision ACL repair

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Adductor Canal Block- Injection -Site AlidocaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site A - after the sartorius muscle crosses over the femoral artery
Adductor Canal Block- Injection -Site AropivacaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site A - after the sartorius muscle crosses over the femoral artery
Adductor Canal Block - Injection -Site BlidocaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site B - before the sartorius muscle crosses over the femoral artery
Adductor Canal Block -Injection -Site CropivacaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site C - as the sartorius muscle crosses over the femoral artery
Adductor Canal Block - Injection -Site BropivacaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site B - before the sartorius muscle crosses over the femoral artery
Adductor Canal Block -Injection -Site ClidocaineAC Block-Injection (lidocaine 2% and ropivacaine 1%) Site C - as the sartorius muscle crosses over the femoral artery
Primary Outcome Measures
NameTimeMethod
Cumulative 24 Hour Oral Morphine Equivalent Consumption24 hours

Post-Operative Analgesia

Motor Power - Peak Force as measured by a dynamometer30 Minutes post Block

Percentage decrease in quadriceps motor strength at 30 minutes following adductor canal block compare to baseline

Secondary Outcome Measures
NameTimeMethod
Opioid ConsumptionDuring surgical procedure

Intra-operative opioid consumption

Total opioids in Post Anesthetics (PAC)Total length of time in PACU (total time in minutes from arrival in PACU to discharge to the Surgical Day Care is between 60-180 minutes

Cumulative oral morphine equivalent consumption in PACU

Pain Scores - Questionnaire24 hours post block

Area under the curve for rest pain scores plotted against time during the first 24 hours

Patient Satisfaction - Questionnaire24 hours postoperatively

Patient satisfaction with analgesia - NRS Pain Scale 0(no pain to 10(worst pain)

Hospital Discharge (Time to hospital discharge)Same day as surgical procedure

Time to hospital discharge

Nerve Block Complications24 hours postoperatively and 2 weeks postoperatively

Presence/absence of nerve block complications during the first 24 hours postoperatively and 2 weeks after surgery

Quality of Recovery (QoR-15)24 hours postoperatively

Quality of recovery measured using the QoR-15 at 24 hours postoperatively

Trial Locations

Locations (1)

Women's College Hospital

🇨🇦

Toronto, Ontario, Canada

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