Unicondylar knee arthroplasty versus total knee arthroplasty in adults with isolated medial osteoarthritis: A matched study protocol

BACKGROUND: The choice between unicondylar knee arthroplasty (UKA) and total knee arthroplasty (TKA) is likely to have long-term implications for patient-reported health outcomes. However, high-quality studies that compare the outcomes of TKA and UKA and their effects are still lacking in the literature. Thus, the aim of the present study was to compare the UKA and TKA techniques with regard to functional outcomes and perioperative complications in patients who had isolated medial osteoarthritis. METHODS: This was a retrospective, single-center, matched-controlled study performed with approval of our hospital (Kunshan hospital of Traditional Chinese Medicine affiliated to Nanjing University of Traditional Chinese Medicine), with the ethics number KZY2020–37. To reduce the effect of selection bias and potential confounding in this observational study, a 1:1 matching algorithm was applied. The groups were split by sex, age to within 6 years, and body mass index within 5 kg/m(2). Thus, we retrospectively reviewed the records of 240 consecutively enrolled patients who underwent UKA and 240 patients who underwent TKA from January 2013 to June 2015 from the database of our institution. Written informed consent was obtained from all subjects participating in the trial. Clinical outcomes included range of motion, Short Form 12 score, new Knee Society Score, Western Ontario and McMaster Universities Arthritis Index, and the complications. The outcome measures were evaluated by a physiotherapist and were assessed preoperatively and postoperatively at 6 months and 2 years. The mean follow-up time was 3 years. CONCLUSION: We hypothesized that there was no significant difference between the 2 groups in terms of postoperative outcomes. TRIAL REGISTRATION: Our study was registered in Research Registry (researchregistry5828).