Ambulatory unicompartmental knee arthroplasty: Short outcome of 50 first cases.

INTRODUCTION: The reduction in length of stay (LOS) in orthopedic surgery has been steady for several years. For the past 3 or 4 years in France, the trend toward outpatient surgery has been growing upwards, as it is a goal for hospital administration.

MATERIALS AND METHODS: This is a prospective, continuous, mono-centric, single operator study on 56 UKAs. Included were all UKAs carried out between January 2014 and December 2015, meeting the following criteria: voluntary patients, supportive family environment, absence of comorbidity (oral anticoagulants, diabetes, obesity), ASA score≤3. Preoperatively, patients received: Dexamethasone 2mg/10kg, Tranexamic acid 2g, Cefazolin 2g IV. All patients were operated on under general anesthesia with the same technique: Alpina® (Zimmer-Biomet) uni-prosthesis without tourniquet. The arthrotomy was closed after a capsular injection of a solution of 150mg Ropivacaine+30mg Bi-Profenid® . Patient discharge on the same day evening was authorized by both surgeon and anesthesiologist. Three criteria were quantified: number of patients seen before the date of the first consultation for the removal of stitches (around day 12), Visual Pain Scale (10 points scale) on the first 12 days, and the level of satisfaction at the one-month postoperative visit.

RESULTS: Six patients (11%) were not included in the ambulatory program during the initial consultation. Three patients were not able to be discharged on the same day evening due to nausea and therefore remained hospitalized for one night. Eighteen patients (38%) were reviewed before D10: 13 patients were reviewed between D1 and D4 for bleeding through the dressing and 5 for pain not controlled by level 1 and 2 analgesics. The Visual Pain Scale (VPS) reached level 6±2 by the 2nd day and then dropped to 1±1 by the 12th day. At 1 month, 85% of the patients were satisfied or very satisfied with their care. There were no general or localized complications.

DISCUSSION: Ambulatory UKA surgery is possible for most patients. The inclusion rate for ambulatory UKA was 88% for Berger RA in 2010, therefore very close to this study rate of 89%. Ambulatory care is not only a change in surgical and anesthetic practice but a totally new management process involving all medical and non-medical actors. Ambulatory UKA surgery is feasible and safe for most patients.

LEVEL OF EVIDENCE: IV, retrospective cohort study.