Outpatient surgery for unicompartmental knee arthroplasty is effective and safe

Knee Surg Sports Traumatol Arthrosc. 2017 Sep;25(9):2659-2667. doi: 10.1007/s00167-015-3680-y. Epub 2015 Jul 1.


Purpose: There has been increasing interest in accelerated programs for knee arthroplasty. We examined the efficacy and safety of an outpatient surgery (OS) pathway in patients undergoing unicompartmental knee arthroplasty (UKA).

Methods: This case-controlled study evaluates patients operated for UKA in an OS pathway (n = 20) compared to rapid recovery (RR), the current standard (n = 20). We investigated whether patients could be discharged on the day of surgery, resulting in comparable or better outcome by means of adverse events (AEs) in terms of pain (numerical rating scale, NRS), incidences of postoperative nausea and vomiting (PONV) and opiate use (<48 h postoperatively), complication and readmission rates (<3 months postoperatively). Patient-reported outcome measures (PROMS) were obtained preoperatively and 3 months postoperatively.

Results: Postoperative pain (NRS > 5) was the most common reason for prolonged hospital stay in the OS pathway. Eighty-five per cent of the patients were discharged on the day of surgery, whereas 95 % of the patients were discharged on postoperative day 3 in the RR pathway. Overall, median pain scores in both pathways did not exceed a NRS score of 5, without significant differences (RR vs. OS) in the number of patients with PONV (4 vs. 2) and opiate use (11 vs. 9) <48 h postoperatively. At 3 months postoperatively, no significant differences were found for AEs and PROMS between both pathways.

Conclusion: The results of this study illustrates that an OS pathway for UKA is effective and safe with acceptable clinical outcome. Well-established and adequate standardized protocols, inclusion and exclusion criteria and a change in mindset for both the patient and the multidisciplinary team are the key factors for the implementation of an OS pathway.

Level of evidence: Case-control study, Level III.

Keywords: Early mobilization; Outpatient surgery; PONV; Pain management; Partial knee arthroplasty; Short-stay; Unicompartmental knee arthroplasty.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Ambulatory Surgical Procedures*
  • Arthroplasty, Replacement, Knee / methods*
  • Female
  • Follow-Up Studies
  • Hemiarthroplasty / methods*
  • Humans
  • Length of Stay
  • Male
  • Middle Aged
  • Pain, Postoperative / diagnosis
  • Pain, Postoperative / etiology
  • Pain, Postoperative / therapy
  • Patient Reported Outcome Measures
  • Pilot Projects