Adductor Canal Block for Medial Compartment Knee Arthroplasty

Wake Forest University Health Sciences150 enrolled

Overview

This study will evaluate the affects of a single injection ultrasound-guided adductor canal block for patients undergoing robotic-assisted (MAKOplasty) medial UKA (unicompartmental knee arthroplasty). Specifically, this study will compare the adequacy of postoperative analgesia provided by the adductor canal block with that provided by single injection lumbar plexus blockade. The working hypothesis is that the analgesia provided by the adductor canal block will be equivalent to the analgesia provided by the lumbar plexus block. The primary outcome will be a comparison of verbal numerical pain scores at rest and with movement over the first 24 hours following nerve blockade.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Enrollment

150

Conditions

Postoperative Analgesia Medial Unicompartmental Knee Arthroplasty

Interventions

Eligibility

Sex: ALLMin age: 18 YearsMax age: 85 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients aged 18-85 * Undergoing unilateral robotic-assisted (MAKOplasty) medial compartment knee arthroplasty at Wake Forest University Baptist Medical Center. * Must give written informed consent for anesthesia including subarachnoid blockade and peripheral nerve blockade of both the lumbar plexus and adductor canal. * Must consent to the performance of a sham block at the site to which they are not randomized. * Must also be reliable to give accurate verbal pain scores postoperatively. Exclusion Criteria: * Contraindication to adductor canal blockade or lumbar plexus blockade (including significant coagulation abnormalities) * History of opioid addiction or current chronic pain therapy for pain other than at the surgical site that is being treated with high-dose opioids (extended release opioids or \> 40mg oxycodone equivalents per day) * Allergy to study medications * Failure to adequately place either the adductor canal or lumbar plexus blocks. * Patients who decline or have a contraindication to subarachnoid blockade will also be excluded from the study. * Pregnancy.

Outcomes

Primary Outcomes

Verbal Pain Scores at 6 Hours Post Nerve Blockade.

Comparison of verbal numerical pain scores at rest and with movement 6 hours following nerve blockade. The score range is 0-10 with higher scores denoting worse outcomes.

Time frame: 6 hours post block.

Secondary Outcomes

Opioid Consumption

Comparison of cumulative opioid consumption over 24 hour period between adductor canal block and lumbar plexus block.

Time frame: 6, 12, 18, and 24 hours

Time to First Analgesic

Time to first analgesic between two groups: adductor canal block and lumbar plexus block.

Time frame: 24 hours

Opioid Related Side Effects

Occurrence of opioid related side effects (nausea, vomiting and pruritus) between two groups: adductor canal block and lumbar plexus block.

Time frame: 6, 12, 18, and 24 hours

Quadriceps Motor Strength

Comparison of quadriceps motor strength at 6 hour post nerve block between two groups: adductor canal block and lumbar plexus block. The score range is 0-5, with higher scores denoting better outcomes.

Time frame: 6 hours