K982160 · Encore Orthopedics, Inc. · KRO · Mar 17, 1999 · Orthopedic
Device Facts
Record ID
K982160
Device Name
HINGED KNEE
Applicant
Encore Orthopedics, Inc.
Product Code
KRO · Orthopedic
Decision Date
Mar 17, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 888.3510
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The Hinged Knee is a tri-compartmental prosthesis of the total condylar type. The system consists of femoral, tibial and patellar components. It's intended use is to allow replacement of the knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infection, revision or connective tissue disorders. The Hinged Knee provides joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL and the iliotibial band.
Device Story
Hinged Knee is a tri-compartmental total condylar prosthesis; consists of femoral, tibial, and patellar components. Designed for surgical replacement of knee joint in cases of significant bone loss or ligamentous deficiency (MCL, LCL, PCL, ACL, iliotibial band). Provides joint stability. Used by orthopedic surgeons in clinical/hospital settings. Requires fixation with acrylic bone cement. Benefits patients by restoring joint function and stability in complex revision or trauma scenarios.
Clinical Evidence
No clinical data provided; substantial equivalence based on design, material, and intended use comparisons.
Technological Characteristics
Tri-compartmental total condylar prosthesis; femoral, tibial, and patellar components. Materials include metal and polymer. Requires acrylic bone cement for fixation. Minimum polyethylene thickness under condyles is 8.0mm.
Indications for Use
Indicated for patients requiring knee joint replacement due to significant bone loss or ligamentous deficiencies (MCL, LCL, PCL, ACL, or iliotibial band non-function) resulting from tumors, trauma, infection, revision, or connective tissue disorders. Intended for cemented use only.
Regulatory Classification
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).
Submission Summary (Full Text)
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3/17/99
## K982160
## Summary of Safety and Effectiveness
Encore Orthopedics®, Inc. 9800 Metric Blvd Austin, TX 78758 512-832-9500
Trade Name: Hinged Knee
Common Name: Hinged Knee
Classification Name: Knee joint femorotibial metal/polymer constrained cemented prosthesis, 21 CFR 888.3510.
The Hinged Knee is a tri-compartmental prosthesis of the total condylar type. The Description: system consists of femoral, tibial and patellar components. It's intended use is to allow replacement of the knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infection, revision or connective tissue disorders. The Hinged Knee provides joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL and the iliotibial band.
Comparable Features to Predicate Device(s): Features comparable to predicate devices include same indications for use, same materials and similar geometry.
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Image /page/1/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle or bird-like figure with three curved lines forming its body and wings. The logo is surrounded by text arranged in a circular pattern, spelling out "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA".
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
MAR 1 7 1999
Ms. Debbie De Los Santos Regulatory/Clinical Specialist Encore Orthopedics, Inc. 9800 Metric Boulevard Austin, Texas 78758
K982160 Re: Encore Hinged Knee Regulatory Class: II KRO Product Code: Dated: February 10, 1999 February 11, 1999 Received:
Dear Ms. De Los Santos:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). This decision is based on this device being equivalent only to similar devices labeled and intended to be fixed within bone with acrylic "bone You may, therefore, market your device subject to cement." the general controls provisions of the Act and the following limitations:
- The thinnest tibial inserts available are the nominal 1. "8mm" thick inserts, which have a minimum polyethylene thickness under the condyles of 8.0mm.
- 2. This device may not be labeled or promoted for non-cemented use.
- 3 . All labeling for this device, including package label and labeling included within the package, must prominently state that the device is intended for cemented use only.
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Page 2 - Ms. Debbie De Los Santos
- Any non-cemented fixation of this device is considered 4 . investigational and may only be investigated as a significant risk device in accordance with the investigational device exemption (IDE) regulation under 21 CFR, Part 812. All users of the device for non-cemented fixation must receive approval from their respective institutional review boards (IRBs) and the Food and Druq Administration (FDA) to conduct the investigation.
The general controls provisions of the Act include requirements for annual reqistration, listing of devices, good manufacturing practices, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Requlations, Title 21, Parts 800 to 895. ਚੇ substantially equivalent determination assumes compliance with the Good Manufacturing Practice for Medical Devices: General (GMP) regulation (21 CFR Part 820) and that, through periodic GMP inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal Laws or Regulations.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification immediately. An FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be
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Page 3 - Ms. Debbie De Los Santos
obtained from the Division of Small Manufacturers Assistance obearned from the Breazion of 638-2041 or at (301) 443-6597, at its internet address "dsmo@fdadr.cdrh.fda.gov".
Sincerely yours,
Celia M. Whitten, Ph.D., M.
Celia M. Witten, Ph.D., M.D. Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number (if known): ____________________________________________________________________________________________________________________________________________________
Device Name: Hinged Knee
Indications For Use:
## Hinged Knee Indications For Use
The Hinged Knee is a tri-compartmental prosthesis of the total condylar type. The system consists of femoral, tibial and patellar components. It's intended use is to allow replacement of the knee joint in which significant bone loss and/or ligamentous deficiencies have occurred due to tumors, trauma, infection, revision or connective tissue disorders. The Hinged Knee provides joint stability when any or all of the following structures are non-functional: MCL, LCL, PCL, ACL and the iliotibial band.
## (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurence of CDRH, Office of Device Evaluation (ODE)
| (Division Sign-Off) | |
|-----------------------------------------|---------|
| Division of General Restorative Devices | |
| 510(k) Number | K982160 |
| Prescription Use | X |
|----------------------|---|
| (per 21 CFR 801.109) | |
OR
| Over-The-Counter Use | |
|--------------------------|--|
| (Optional Format 1-2-96) | |
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