This is a prospective, multi-center study, designed to assess mid-term performance of the MOTO Medial® UKA, with patient report outcomes, clinical findings and radiographic analysis. Additionally, several perioperative factors, medical and surgical history will be evaluated. Implant survival and complications will be detailed throughout the study. Data from pre-operative evaluation, day of surgery, and post-operatively at 4 weeks, 6 months, and years 1, 2 & 5, will be collected.