Prospective Post Market Clinical Follow-Up of the Primary Knee Endoprosthesis BPK-S Integration

Inclusion Criteria: * Congenital or acquired knee joint defects/deformation or * Defects or malfunction of the knee joint or * Arthrosis (degenerative, rheumatic) or * Post-traumatic arthritis or * Symptomatic knee instability or * Reconstruction of flexibility or * Patients with metal hypersensitivity (ceramic tibia/femur) Exclusion Criteria: * Illnesses which can be treated without using a knee joint implant. * Acute or chronic infections near the implantation * Systemic diseases and metabolic disorders * Serious osteoporosis * Serious damage to the bone structures that impedes stable implantation of the implant components * Diseases that impair bone growth, e.g. cancer, renal dialysis, osteopenia, etc. * Bone tumors in the area of the implant anchoring * Obesity or overweight of the patient * Overload of the knee implant to be expected * Abuse of medication, drug abuse, alcoholism or mental disease * Lack of patient cooperation * Sensitivity to foreign matter in the implant materials * Patients under the age of 18 * Patients participating in another trial