Identification. A knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis is a two-part device intended to be implanted to replace part of a knee joint in the treatment of primary patellofemoral arthritis or chondromalacia. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes a component made of alloys, such as cobalt-chromium-molybdenum or austenitic steel, for resurfacing the intercondylar groove (femoral sulcus) on the anterior aspect of the distal femur, and a patellar component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those devices intended for use with bone cement (§ 888.3027). The patellar component is designed to be implanted only with its femoral component.

Classification. Class II. The special controls for this device are:

FDA's:

“Use of International Standard ISO 10993 ‘Biological Evaluation of Medical Devices—Part I: Evaluation and Testing,’ ”

“510(k) Sterility Review Guidance of 2/12/90 (K90-1),”

“Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone Cement,”

“Guidance Document for the Preparation of Premarket Notification (510(k)) Applications for Orthopedic Devices,” and

“Guidance Document for Testing Non-articulating, ‘Mechanically Locked’ Modular Implant Components,” and

International Organization for Standardization's (ISO):

ISO 5832-3:1996 “Implants for Surgery—Metallic Materials—Part 3: Wrought Titanium 6-Aluminum 4-Vandium Alloy,”

ISO 5832-4:1996 “Implants for Surgery—Metallic Materials—Part 4: Cobalt-Chromium-Molybdenum Casting Alloy,”

ISO 5832-12:1996 “Implants for Surgery—Metallic Materials—Part 12: Wrought Cobalt-Chromium-Molybdenum Alloy,”

ISO 5833:1992 “Implants for Surgery—Acrylic Resin Cements,”

ISO 5834-2:1998 “Implants for Surgery—Ultra-high Molecular Weight Polyethylene—Part 2: Moulded Forms,”

ISO 6018:1987 “Orthopaedic Implants—General Requirements for Marking, Packaging, and Labeling,”

ISO 7207-2:1998 “Implants for Surgery—Components for Partial and Total Knee Joint Prostheses—Part 2: Articulating Surfaces Made of Metal, Ceramic and Plastic Materials,” and

ISO 9001:1994 “Quality Systems—Model for Quality Assurance in Design/Development, Production, Installation, and Servicing,” and

American Society for Testing and Materials':

F 75-92 “Specification for Cast Cobalt-28 Chromium-6 Molybdenum Alloy for Surgical Implant Material,”

F 648-98 “Specification for Ultra-High-Molecular-Weight Polyethylene Powder and Fabricated Form for Surgical Implants,”

F 799-96 “Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Forgings for Surgical Implants,”

F 1044-95 “Test Method for Shear Testing of Porous Metal Coatings,”

F 1108-97 “Titanium-6 Aluminum-4 Vanadium Alloy Castings for Surgical Implants,”

F 1147-95 “Test Method for Tension Testing of Porous Metal Coatings,”

F 1537-94 “Specification for Wrought Cobalt-28 Chromium-6 Molybdenum Alloy for Surgical Implants,” and

F 1672-95 “Specification for Resurfacing Patellar Prosthesis.”