The study objective is to evaluate safety and performance of the ORIGIN® PS (postero-stabilized) Modular devices and associated instruments, more precisely to evaluate safety by the proportion of patients requiring a revision (i.e. revision rate) at 2-6 months, 1y and 2y post-procedure and to evaluate performance by means of a Knee Society Score (KSS) Score at 2-6 months, 1y and 2y post procedure.

The hypothesis raised for this study, regarding the scoring, is that patients will experience a marked improvement in the natural feel of the prosthesis during the first year after the surgery, and slightly significant improvement at the following interval of 2 years. The overall patient satisfaction is expected to be improved after 2 years follow-up with ORIGIN® PS Modular.

The study is ambispective, post market, non-comparative, non-randomized, multicentric and observational in which 200 patients will be enrolled to evaluate the safety and performance of the ORIGIN® PS Modular devices and associated instruments.

Patients will be included in the study during 18 months (inclusion window) and followed-up for 24 months.

Inclusion Criteria:

• Male or female over 18 years of age.
• Patient, or if applicable, his or her guardian or legal representative, willing to give informed consent.
• Clinically indicated for first intention total knee replacement.
• Geographically stable and willing to return for all follow-up visits or, at a minimum, to complete the patient self-report score.

Exclusion Criteria:

• Vulnerable subject (as defined in ISO-14155)
• Acute or chronic, local or systemic infection,
• Muscular, ligamental, neurological, psychological or vascular deficits,
• Bone destruction or poor bone quality likely to affect implant stability.
• Any concomitant condition likely to affect implant integration or function,
• Allergy or hypersensitivity to any of the materials used,
• For devices in CoCr Mo (ISO 5832/4): renal and hepatic impairment,
• Hip Knee Ankle (HKA) angle < 165° or > 195°,
• Severe collateral ligament deficiency (requiring a more constrained prosthesis),
• Major anatomical deformities,
• Severe flexion contracture or severe recurvatum,
• Revision of a partial or total knee prosthesis,
• Non-extractible material (e.g., screw, plate, intramedullary nail, osteosynthesis material) which can create a conflict with any component of the prosthesis,
• Distal and/or posterior and/or anterior femoral bone loss which exceeds the femoral component thickness,
• Proximal tibial bone loss which exceeds the tibial component thickness (tibial tray + tibial insert),
• Bone degradation requiring an anchoring stem for femoral component

Patients who have provided consent for the collection of their data and met the protocol eligibility criteria will be enrolled into this observational non-comparative ambispective multicentric study.