Introduction: There are a lot of debates on the advantages and safety profile of one stage bilateral knee arthroplasty. Most of the studies focus on total knee replacement, and it may not be applied directly to unicompartmental knee replacement (UKR). We would like to compare the early results of one and two stage bilateral UKR in our center. Methods: This is a retrospective review of all the bilateral medial UKR done in our center in 2018–2019. Patients’ demographic data, operative time, postoperative blood, length of stay (LOS) and complications were recorded. The number of admissions, pre-operative assessment sessions (PAS), and weeks of post-operative physiotherapy were analyzed. Clinical outcome was measured by Knee society knee score and range of motion (ROM). Results: Our center performed 97 UKR in 2018–2019, with 50 UKR performed in 25 patients, among which 16 received one stage while 9 received two stage bilateral UKR. Both groups had similar mean age, BMI, sex ratio, ASA grading, pre-operative knee score and ROM. Patient in the one stage group required only 1 PAS/admission/operation to treat both knees with a mean LOS of 7.3 days and 7.8 weeks of physiotherapy, while those in the two stage group required 2 PAS/admissions/operations with a mean cumulative LOS of 9.8 days and 14.1 weeks of physiotherapy. The mean cumulative operative time was similar for both groups but the one stage group only required 1 operative session. There was no difference in blood loss and there was no transfusion or complication. The post-operative knee score and ROM at 3 and 6 months were similar for both groups. Conclusion: In suitable patients with bilateral medial OA knee, one stage bilateral UKR offers simliar early clinical outcome with shorter rehabilitation duration but without increasing complications compared with two stage. Resources can therefore be better utilized.
Minimally invasive unicompartmental knee replacement: Midterm clinical outcome
