Patients who received a total knee endoprosthesis BPK-S Integration between 2011 and 2013 will be invited to participate in this PMCF study provided sufficient source data documentation is available regarding preoperative, intraoperative and early postoperative follow-up assessments.

Only patients providing written informed consent prior to any study data collection can take part in the study.

Preoperative, intraoperative and early postoperative data (3 months, 1 year and 2 years after implantation) will be collected retrospectively. Additional long-term follow-up of one visit (year 7 after implantation) will be documented prospectively.

Only parameters assessed in clinical standard care for follow-up (implant control) visits will be collected for this PMCF study.

Radiological assessment of the implanted prosthesis will only be conducted if medically indicated according to the investigator. No additional study related assessment will be performed.

Only anonymized data will be used in this observational study to protect patient privacy. No personally identifiable information will be collected.

Inclusion Criteria:

• Patients that received a total primary knee endoprosthesis BPK-S Integration (Co28Cr6Mo) between 2011 and 2013
• Patients that agree to participate and give written informed consent to the anonymized retrospective and prospective data collection within the study

Exclusion Criteria:

No study specific exclusion criteria are defined for this PMCF study.

Patients that received a BPK-S Integration in the variant CoCr as primary total knee endoprosthesis between 2011 and 2013 implanted by the investigator