The results of TKP (Total Knee Prosthesis) are satisfactory but do not reach those of THP (Total Hip Prosthesis) in terms of indolence and function. By using an all-ceramic friction torque, identical to that of the hip, the promotor of this Clinical Investigation expects to obtain an improvement in term of indolence, ability to perform heavy activities, knee stability and an improvement in the long-term survival of TKP, while at the same time, a decrease in the rate of re-intervention in young patients.

The aim of this study is to evaluate the all-ceramic knee prosthesis, according to clinical and radiological criteria of usual follow-up of a TKP for knee osteoarthritis, at 12 months.

Evaluation of clinical and radiographic endpoints at 12 months:

- Clinical: functional scores (Oxford and International Knee Society IKS), pain (from 0 to 6, better to worse outcome), knee mobility in flexion and extension (degrees), frontal and sagittal stability (in degrees and mm), joint sounds, Forgotten Joint Score (FJS).

The scores are mostly qualitative and all of them will be globally evaluated by the investigator regarding to the patient status.

-Radiographic: X-rays of the front and profile of the prosthesis, positioning of the implants (angle, axis), existence of borders (bone cement, prosthesis cement), presence of osteolysis or any notable element.

MRI will be performed to evaluate the creation of a specific fibrous tissue around the joint that is expected with a ceramic on ceramic bearing.

Inclusion Criteria:

• Previously active adult under 70 years of age with disabling knee osteoarthritis resistant to medical treatments (anti-inflammatories, infiltrations, analgesics), with a frontal deformity < 10° for a primary implantation
• Written informed consent by the patient
• Patients affiliated to the French social security system

Exclusion Criteria:

• Knee deformity > 10
• Obesity (BMI > 30)
• Inflammatory rheumatism
• History of infection
• Poor skin coverage at the knee joint
• Known allergy to the materials used and/or anesthetic used in the surgery
• Repeated falls, major neurological disorders, mental or neuromuscular disorders which can be a source of post-operative complications
• Significant functional deficit of the collateral ligaments
• Positive serum or urine pregnancy test for woman with child bearing potential. Pregnancy or within 48 hours post-partum or breast feeding women
• Phobic patient refusing to have an MRI
• Patient with a contraindication to have an MRI (active medical devices, metal implants, etc.)
• Patient under legal protection
• Patient participating in another Clinical Investigation
• Post fracture osteoarthritis
• Osteoporosis
• Anatomical configuration not allowing the implant to be fixed (depending on size constraints)
• Disabling comorbidity upon any resumption of physical activity