Physica System KR Vs Physica System CR (K-20)

Inclusion Criteria: 1. Males and females of any race requiring a total knee replacement and suitable for the use of one of the two configurations of the Physica system. 2. Age ≥ 18 years old, 3. Patients who are suffering from non-inflammatory degenerative joint disease (NIDJD): including knee osteoarthritis, post-traumatic knee arthritis, avascular necrosis; or patient who are suffering from inflammatory joint disease including rheumatoid arthritis. 4. Suitable candidates for TKR who have undamaged and functional collateral ligaments 5. Suitable candidates for TKR with Physica KR and CR who have an undamaged and functional posterior cruciate ligament. 6. Patients who understand the conditions of the study and are willing and able to comply with the prescribed rehabilitation and to perform all scheduled follow-up visits. 7. Patients who have signed the Ethics Committee/IRB approved study-specific Informed Consent Form prior to the surgery. Exclusion Criteria: 1. Patients with severe instability of the knee joint secondary to the absence of collateral ligament integrity and/or function. 2. Patients with active or any suspected infection (on the affected knee or systemic) 3. Previous partial knee replacement (unicompartmental, bicompartmental or patellofemoral joint replacement), patellectomy, high tibial osteotomy 4. Patients with significant bone loss on femoral or tibial joint side 5. Current treatment for malignant and/or life-threatening nonmalignant disorders 6. Patients with known incompatibility or allergy to the product materials, and/or metal hypersensitivity to implant materials 7. Patient with open epiphyses (immature patient with active bone growth). 8. Vascular insufficiency of lower limbs severe enough to interfere with the study evaluation 9. Patients with bone stock compromised by disease, infection or prior implantation that cannot provide adequate support and/or fixation to the prosthesis 10. Patients with systemic or metabolic disorders leading to progressive bone deterioration which may impair fixation and stability of the implant 11. Any concomitant disease and dependence that might affect the performance of the implanted prosthesis 12. Any clinically significant pathology based on clinical history that the Investigator feels may affect the study evaluation (e.g. primary osteoporosis with significant bone loss, haemophilic disease, septicaemia, persistent acute or chronic osteomyelitis) 13. Patients who have significant neurological or musculoskeletal disorders or disease that may adversely affect gait and compromise functional recovery and evaluation 14. Patients who have neuromuscular or neurosensory deficit which would limit the ability to assess the performance of the device 15. Previous history of infection in the affected joint and/or other local/systemic infection that may affect the prosthetic joint 16. Any psychiatric illness that would prevent comprehension of the details and nature of the study 17. Patients currently participating in any other surgical intervention studies or pain management studies 18. Female patients who are pregnant, nursing, or planning a pregnancy.