Calypso Knee System Clinical Study, OUS

A study to evaluate the safety and effectiveness of the Calypso Knee System when used in subjects with symptomatic osteoarthritis of the medial compartment of the knee.

Inclusion Criteria: 1. Participants age - 25 to 65 years 2. Body Mass Index (BMI) of \< 35, Weight \< 300 lbs (136 kg) 3. Knee osteoarthritis pain on the inner side of knee that has continued after at least 6 months of non-operative treatment Exclusion Criteria: 1. Symptoms of osteoarthritis in the other knee or in lateral (outer) or patellofemoral compartments of the target knee 2. Knee ligament or meniscal instability 3. Other bone or joint conditions such as Rheumatoid arthritis, Paget's disease, Charcot's disease or general conditions such as allergy or hypersensitivity to certain metals, active infection, certain neurological conditions, use of medication such as steroids or chemotherapy that could impact study participation or results