(88 days)
The MOST System is intended to replace the proximal, distal or total femur and/or the proximal tibia, especially in cases that require extensive resection and restoration. Replacement of the distal femur would also include replacement of the proximal tibia and possible resurfacing of the patella, if necessary. Proximal femoral replacement components are available for press-fit or cemented applications. Components used for replacement of the distal femur and proximal tibia are cemented. Specific diagnostic indications for use of the MOST include:
- metastatic diseases (e.g., osteosarcomas, chondrosarcomas, giant cell tumors, bone tumors) and trauma requiring extensive resection(s) and replacement(s) of the proximal and/or distal femur and/or proximal tibia;
- patient conditions of non-inflammatory degenerative joint disease (NIDJD), e.g., avascular necrosis, osteoarthritis and inflammatory (IJD), e.g. rheumatoid arthritis, requiring extensive resection(s) and replacement(s) of the proximal and/or distal femur and/or proximal tibia; and
- revision cases requiring resection(s) and replacement(s) of the proximal, distal or total femur and/or proximal tibia.
The MOST Options System (MOST) is used for the replacement of the proximal, distal or total femur and/or the proximal tibia. Replacement of the distal femur would also include replacement of the proximal tibia and possible resurfacing of the patella, if necessary. Unlike primary hip and knee systems, this system can be used where extensive femoral and/or tibial resection and restoration is required (e.g., oncology cases). Modularity of the system allows for the resection of varying amounts of the femur and the proximal tibia (and patella, if necessary) before implantation. A total replacement is possible in cases where no part of the femur can be salvaged. Moreover, the system provides additional options for revision or severe bone loss of the tibia. The components of the MOST System include:
- a distal femoral replacement (Condylar End or Hinged Femur) which mates with a tibial component via a hinge type mechanism (Hinge-Kit or 4mm Hinge Kit):
- a proximal femur replacement that is available in two designs to address the presence or absence of the greater trochanter;
- intramedullary (I/M) stems with Cancellous Structured Titanium (CSTi) and MOST segments which will be used in conjunction with the proximal and distal femoral replacements, the Proximal Tibia and the MOST Revision Stem Adapter;
- an all poly patella;
- a proximal tibia replacement (Proximal Tibia or Hinged Tibia) which mates with the Proximal Tibia Insert and Hinged Tibia Insert, respectively and features a distal female taper for attachment of a MOST Revision Stem Adapter, Sulzer Revision Stems or Hinged Tibia Stem Plug (Hinged Tibia only);
- femoral and tibial spacers for use in conjunction with the Hinged Femur and Hinged Tibia, respectively to augment uni-compartmental or bi-compartmental defects; and
- revision stem adapter with and without CSTi coating used to convert the MOST taper to the Sulzer taper.
I am sorry, but based on the provided text, there is no information about acceptance criteria, device performance, sample size, ground truth establishment, or study designs (MRMC, standalone). The document is a 510(k) summary for a medical device called the "MOST Options System," focusing on its description, intended use, and substantial equivalence to other marketed devices. It does not contain the results of any performance studies to demonstrate that the device meets specific acceptance criteria.
§ 888.3510 Knee joint femorotibial metal/polymer constrained cemented prosthesis.
(a)
Identification. A knee joint femorotibial metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits translation or rotation in one or more planes and has components that are linked together or affined. This generic type of device includes prostheses composed of a ball-and-socket joint located between a stemmed femoral and a stemmed tibial component and a runner and track joint between each pair of femoral and tibial condyles. The ball-and-socket joint is composed of a ball at the head of a column rising from the stemmed tibial component. The ball, the column, the tibial plateau, and the stem for fixation of the tibial component are made of an alloy, such as cobalt-chromium-molybdenum. The ball of the tibial component is held within the socket of the femoral component by the femoral component's flat outer surface. The flat outer surface of the tibial component abuts both a reciprocal flat surface within the cavity of the femoral component and flanges on the femoral component designed to prevent distal displacement. The stem of the femoral component is made of an alloy, such as cobalt-chromium-molybdenum, but the socket of the component is made of ultra-high molecular weight polyethylene. The femoral component has metallic runners which align with the ultra-high molecular weight polyethylene tracks that press-fit into the metallic tibial component. The generic class also includes devices whose upper and lower components are linked with a solid bolt passing through a journal bearing of greater radius, permitting some rotation in the transverse plane, a minimal arc of abduction/adduction. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.