The goal of this observational study is to determine the incidence of dislodgement for adductor canal catheters after total knee arthroplasty on post-operative day 1. We will also attempt to identify factors associated with secondary catheter failure.

Total knee arthroplasty (TKA) is a common procedure for indications including osteoarthritis and malignancy involving the knee, with over 55,285 knee replacements performed between 2020-2021 in Canada. Ultrasound guided continuous adductor canal block (cACB) is the standard of care for postoperative analgesia for this procedure. The catheter is not always as effective at providing analgesia as would be expected - which could be due to displacement of the catheter. This displacement is most likely to occur peri-operatively or during physiotherapy post-operatively and as such, post-operative assessments can provide useful insight into causes of secondary failure. This prospective observational study aims to estimate the cACB dislodgment on POD 1 rate at a high volume, tertiary care referral centre, and identify factors associated with dislodgement and clinical sequelae. As this is an observational/QI study of the current standard of care at Sunnybrook Health Sciences Centre, anesthesiologists are free to use the cross sectional versus parallel insertion of the cACB per their discretion.

Inclusion Criteria:

• Patients scheduled for Total Knee Arthroplasty
• Older than 50 years

Exclusion Criteria:

• Body Mass Index greater than 40
• Chronic opioid consumption (greater than 30mg oral morphine equivalent daily)
• Contraindication to Adductor Canal Catheter

All patients referred to Sunnybrook Health Sciences Centre scheduled for primary total knee arthroplasty

De-identified data will be available upon request

Upon publication, no limit on time

Contact study investigators