Objectives:Many surgeons avoid performing unicompartmental knee arthroplasty (UKA) due to various concerns. Cohort studies showing the satisfactory outcomes of UKA can convince surgeons to use this technique. In this study, we report the mid-term outcomes of UKA in a series of patients with medial compartment knee osteoarthritis.Methods:Seventeen patients with unicompartmental degenerative joint disease of the knee that underwent UKA and were available for final evaluation were included. The mean age of the patients was 63 ± 5.1 years. The mean follow-up of the patients was 37.2 ± 18.3 months. The outcome measures were the Oxford Knee Score (OKS), Knee Society Score (KSS) for knee score and knee function, Knee injury and Osteoarthritis Outcome Score (KOOS), knee range of motion (ROM), and satisfaction rate on a 5-point Likert scale.Results:In the last follow-up visit, the mean of OKS and knee score section of the KSS were 44.6 ± 3.2 and 83.8 ± 2.1, respectively. The mean knee function section of the KSS was measured at 98.2 ± 7.2. The mean KOOS score and the mean knee ROM were 84 ± 9.4 and 134.4 ± 7º, respectively. The mean VAS for pain was 8.9 ± 1.1 (range 8-10) before the operation and 1.2 ± 0.8 (range 0-2) at the last follow-up. All the patients were very satisfied (n=14) or satisfied (n=3) with the results. No postoperative complication or reoperation was recorded during the follow-up.Conclusion:Unicompartmental knee arthroplasty provides satisfactory outcomes and a high survival rate, at least in mid-term follow-up. These findings suggest increased use of UKA in future workups.