[Federal Register Volume 65, Number 45 (Tuesday, March 7, 2000)]
[Notices]
[Pages 12015-12019]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-5467]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. 00N-0018]


Orthopedic Devices; Reclassification of the Knee Joint 
Patellofemorotibial Metal/Polymer Porous-Coated Uncemented Prosthesis 
and the Knee Joint Femorotibial (Uni-compartmental) Metal/Polymer 
Porous-Coated Uncemented Prosthesis

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice of panel recommendation.

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SUMMARY: The Food and Drug Administration (FDA) is announcing for 
public comment two recommendations of the Orthopedic and Rehabilitation 
Devices Panel (the Panel) to reclassify the knee joint 
patellofemorotibial metal/polymer porous-coated uncemented prosthesis 
and the knee joint femorotibial (uni-compartmental) metal/polymer 
porous-coated uncemented prosthesis from class III into class II. The 
Panel made these recommendations after reviewing the reclassification 
petition submitted by the Orthopedic Surgical Manufacturers Association 
(OSMA) and other publicly available information. FDA is also announcing 
for public comment its tentative findings on the Panel's 
recommendations. After considering any public comments on the Panel's 
recommendations and FDA's tentative findings, FDA will approve or deny 
the reclassification petition by order in the form of a letter to the 
petitioner. FDA's decision on the reclassification petition will be 
announced in the Federal Register.

DATES: Submit written comments by June 7, 2000.

ADDRESSES: Written comments to the Dockets Management Branch (HFA-305), 
Food and Drug Administration, 5630 Fishers Lane, rm. 1061, Rockville, 
MD 20852.

FOR FURTHER INFORMATION CONTACT: Peter G. Allen, Center for Devices and 
Radiological Health (HFZ-410), Food and Drug Administration, 9200 
Corporate Blvd., Rockville, MD 20850, 301-594-2036.

SUPPLEMENTARY INFORMATION:

I. Regulatory Authorities

    The Federal Food, Drug, and Cosmetic Act (the act) (21 U.S.C. 301 
et seq.), as amended by the Medical Device Amendments of 1976 (the 
amendments) (Public Law 94-295), the Safe Medical Devices Act of 1990 
(the SMDA) (Public Law 101-629), and the Food and Drug Administration 
Modernization Act of 1997 (the FDAMA) (Public Law 105-115), established 
a comprehensive system for the regulation of medical devices intended 
for human use. Section 513 of the act (21 U.S.C. 360c) established 
three categories (classes) of devices, depending on the regulatory 
controls needed to provide reasonable assurance of their safety and 
effectiveness. The three categories of devices are class I (general 
controls), class II (special controls), and class III (premarket 
approval).
    Under section 513 of the act, devices that were in commercial 
distribution before May 28, 1976 (the date of enactment of the 1976 
amendments), generally referred to as preamendments devices, are 
classified after FDA has: (1) Received a recommendation from a device 
classification panel (an FDA advisory committee); (2) published the 
panel's recommendation for comment, along with a proposed regulation 
classifying the device; and (3) published a final regulation 
classifying the device. FDA has classified most

[[Page 12016]]

preamendments devices under these procedures.
    Devices that were not in commercial distribution prior to May 28, 
1976, generally referred to as postamendments devices, are classified 
automatically by statute (section 513(f) of the act) into class III 
without any FDA rulemaking process. Those devices remain in class III 
and require premarket approval, unless and until the device is 
reclassified into class I or II or FDA issues an order finding the 
device to be substantially equivalent, under section 513(i) of the act, 
to a predicate device that does not require premarket approval. The 
agency determines whether new devices are substantially equivalent to 
previously offered devices by means of premarket notification 
procedures in section 510(k) of the act (21 U.S.C. 360(k)) and 21 CFR 
part 807 of the regulations.
    A preamendments device that has been classified into class III may 
be marketed, by means of premarket notification procedures, without 
submission of a premarket approval application (PMA) until FDA issues a 
final regulation under section 515(b) of the act (21 U.S.C. 360e(b)) 
requiring premarket approval.
    Reclassification of classified postamendments devices is governed 
by section 513(f)(2) of the act. This section provides that FDA may 
initiate the reclassification of a device classified into class III 
under section 513(f)(1) of the act, or the manufacturer or importer of 
a device may petition the Secretary of Health and Human Services (the 
Secretary) for the issuance of an order classifying the device in class 
I or class II. FDA's regulations in Sec. 860.134 (21 CFR 860.134) set 
forth the procedures for the filing and review of a petition for 
reclassification of such class III devices. In order to change the 
classification of the device, it is necessary that the proposed new 
class have sufficient regulatory controls to provide reasonable 
assurance of the safety and effectiveness of the device for its 
intended use.
    Under section 513(f)(2)(B)(i) of the act, the Secretary may, for 
good cause shown, refer a petition to a device classification panel. 
The Panel shall make a recommendation to the Secretary respecting 
approval or denial of the petition. Any such recommendation shall 
contain: (1) A summary of the reasons for the recommendation, (2) a 
summary of data upon which the recommendation is based, and (3) an 
identification of the risks to health (if any) presented by the device 
with respect to which the petition was filed.

II. Regulatory History of the Devices

    The knee joint patellofemorotibial metal/polymer porous-coated 
uncemented prosthesis and the knee joint femorotibial (uni-
compartmental) metal/polymer porous-coated uncemented prosthesis 
intended to be implanted to replace the knee joint or part of the knee 
joint, respectively, are postamendments devices classified into class 
III under section 513(f)(2) of the act. Therefore, the devices cannot 
be placed in commercial distribution for implantation to replace the 
knee joint or part of the knee joint, respectively, unless they are 
reclassified under section 513(f)(2), or subject to an approved 
premarket approval application (PMA) under section 515 of the act.
    This action is taken in accordance with section 513(f)(2) of the 
act and Sec. 860.134, based on information submitted in a petition for 
reclassification by the OSMA received on July 28, 1997, requesting 
reclassification of the knee joint patellofemorotibial metal/polymer 
porous-coated uncemented prosthesis and the knee joint femorotibial 
(uni-compartmental) metal/polymer porous-coated uncemented prosthesis 
from class III into class II (Ref. 1). Consistent with the act and the 
regulation, FDA referred the petition to the Panel for its 
recommendation on the requested changes in classification.

III. Device Descriptions

    The following device descriptions are based on the Panel's 
recommendation and the agency's review.

A. Knee Joint Patellofemorotibial Metal/polymer Porous-Coated 
Uncemented Prosthesis

    A knee joint patellofemorotibial metal/polymer porous-coated 
uncemented prosthesis is a device intended to be implanted to replace a 
knee joint. 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 prostheses that 
have a femoral component made of a cobalt-chromium-molybdenum (Co-Cr-
Mo) alloy or a surface hardened titanium-aluminum-vanadium (Ti-6A1-4V) 
alloy, a tibial component made of an ultra-high molecular weight 
polyethylene (UHMWPe) articulating bearing surface fixed to a metal 
base made of Co-Cr-Mo or Ti-6A1-4V alloy, and a patellar resurfacing 
component made of an UHMWPe component fixed to a metal base made of a 
Co-Cr-Mo- or a Ti-6A1-4V alloy. The femoral component, tibial base, and 
patellar base have a substrate porous coating made of, in the case of 
Co-Cr-Mo components, beads of the same alloy or commercially pure 
titanium powder; and in the case of Ti-6Al-4V components, beads or 
fibers of commercially pure titanium or Ti-6A1-4V alloy, or 
commercially pure titanium powder. The porous coating has a volume 
porosity between 30 to 70 percent, an average pore size between 100 to 
1,000 microns, interconnecting porosity, and a porous coating thickness 
of 600 to 1,500 microns. This generic type of device is designed to 
achieve biological fixation to bone without the use of bone cement. 
This device description does not include mobile bearing knee 
prostheses.

B. Knee Joint Femorotibial (Uni-compartmental) Metal/polymer Porous-
Coated Uncemented Prosthesis

    A knee joint femorotibial (uni-compartmental) metal/polymer porous-
coated uncemented prothesis is a device intended to be implanted to 
replace part of a knee joint. The device limits translation and 
rotation in one or more planes via the geometry of its articulating 
surface. It has no linkage across the joint. This generic type of 
device includes prostheses that have a femoral component made of a 
cobalt-chromium-molybdenum (Co-Cr-Mo) alloy or a surface hardened 
titanium-aluminum-vanadium (Ti-6A1-4V) alloy and tibial component 
composed of an ultra-high molecular weight polyethylene fixed to a 
metal base made of a Co-Cr-Mo or a surface hardened Ti-6A1-4V alloy. 
The femoral component and tibial base have a substrate porous coating 
made of, in the case of Co-Cr-Mo components, beads of the same alloy or 
commercially pure titanium powder, and in the case of Ti-6A1-4V 
components, beads or fibers of commercially pure titanium or Ti-6A1-4V 
alloy, or commercially pure titanium powder. The porous coating has 
volume porosity between 30 to 70 percent, an average pore size between 
100 to 1,000 microns, interconnecting porosity, and a porous coating 
thickness of 600 to 1,500 microns. This generic type of device is 
designed to achieve biological fixation to bone without the use of bone 
cement. This device description does not include mobile bearing knee 
prostheses.

IV. Recommendations of the Panel

    At a public meeting on January 12 and 13, 1998, the Panel 
recommended unanimously that the knee joint patellofemorotibial metal/
polymer porous-coated uncemented prosthesis and recommended (five to 
three) that

[[Page 12017]]

the knee joint femorotibial (uni-compartmental) metal/polymer porous-
coated uncemented prosthesis be reclassified from class III to class II 
(Ref. 2). The Panel believed that class II with the special controls 
(FDA recognized consensus standards and FDA guidance documents for both 
devices, and postmarket surveillance for only the knee joint 
femorotibial (uni-compartmental) metal/polymer porous-coated uncemented 
prosthesis) would provide reasonable assurance of the safety and 
effectiveness of the devices.

V. Risks to Health

    After considering the information in the petition, the Panel's 
deliberations, the published literature, and the Medical Device 
Reports, FDA has evaluated the risks to health associated with the use 
of the knee joint patellofemorotibial metal/polymer porous-coated 
uncemented prosthesis and the knee joint femorotibial (uni-
compartmental) metal/polymer porous-coated uncemented prosthesis. FDA 
now believes that the following are risks to health associated with use 
of the devices: infection, adverse tissue reaction, pain and/or loss of 
function, and revision. FDA notes that these risks to health are also 
associated with the use of the cemented versions of total and partial 
knee joint prostheses.

A. Infection

    Infection is a potential risk to health associated with all 
surgical procedures and implanted devices, and it occurs equally in 
patients implanted with cemented and uncemented knee joint prostheses 
(Ref. 1). The best defenses against infection are preventative 
measures, including selection of patients without known local and/or 
systemic infection, administration of perioperative antibiotics, 
implantation of a sterilized device, and strict adherence to sterile 
surgical technique.

B. Adverse Tissue Reaction

    Adverse tissue reaction is a potential risk to health associated 
with all implanted devices (Ref. 1). If the materials used in the 
manufacture of knee prostheses are not biocompatible, the patient could 
have an adverse tissue reaction. Knee prostheses are made of implant 
materials with an established long history of safe use. In addition, 
the biocompatibility of porous-coated implant materials has been shown 
to be comparable to those of the ``as cast'' noncoated material.

C. Pain and/or Loss of Function

    Pain and loss of knee function can occur with any knee 
arthroplasty. Some of the same kinds of device-related complications 
causing pain and/or loss of function are associated with the 
implantation of both cemented and uncemented knee prostheses. These 
complications include early loosening due to inappropriate patient and/
or device selection, inappropriate surgical technique and/or poor bone 
quality; some forms of metal and/or polyethylene wear which may cause 
osteolysis (dissolution of bone); and component disassembly, fracture, 
and/or failure. Dislocation and instability of a knee prosthesis may be 
due to either inappropriate surgical technique and/or component design 
or failure. However, other device-related complications resulting in 
pain and/or loss of function are directly or uniquely related to the 
porous coating(s) of uncemented knee prosthesis components. These 
complications include incomplete and/or slow biological ingrowth of the 
porous coating, resulting in pain and dislocation/instability of the 
joint, and delamination of porous coating from the prosthesis 
components. Also, inadequate design and/or testing of the metal backing 
of the patellar component of uncemented knee prostheses may cause 
dislocation and instability, which may result in pain and/or loss of 
function.

D. Revision

    The incidence of revision for uncemented knee prostheses is 
comparable to the revision rates of cemented total knee arthroplasty 
(Ref. 1). The major causes for revision of uncemented knee prostheses 
are failure of the metal-backed patellar component or incomplete tibial 
fixation.

VI. Summary of the Reasons for the Recommendations

    After considering the data and information contained in the 
petition and provided by FDA, the open discussions during the Panel 
meeting, and the Panel members' personal knowledge of and clinical 
experience with the devices, the Panel gave the following reasons in 
support of its recommendations to reclassify the two generic type 
devices, the knee joint patellofemorotibial metal/polymer porous-coated 
uncemented prosthesis and the knee joint femorotibial (uni-
compartmental) metal/polymer porous-coated uncemented prosthesis 
intended to replace a knee joint or part of a knee joint, respectively, 
from class III into class II. The Panel believed that both of these 
devices should be reclassified into class II because special controls, 
in addition to general controls, provide reasonable assurance of the 
safety and effectiveness of the devices, and there is sufficient 
information to establish special controls to provide such assurance.

VII. Summary of Data Upon Which the Panel Recommendations Are Based

    In addition to the potential risks to health of the knee joint 
patellofemorotibial metal/polymer porous-coated uncemented prosthesis 
and the knee joint femorotibial (uni-compartmental) metal/polymer 
porous-coated uncemented prosthesis, described in Section V., there is 
reasonable knowledge of the benefits of the devices. Both cemented and 
uncemented knee prostheses provide a decrease in pain or cessation of 
pain and increased mobility and function, post-operatively resulting in 
an overall improved quality of patient life. Specific benefits of 
uncemented knee prostheses are the absence of risks associated with the 
use of bone cement (e.g., embolism and bone cement breakdown) and 
easier revision, if revision should become indicated due to loosening.

VIII. Special Controls

    FDA believes that the special controls identified below, in 
addition to general controls, are adequate to control the identified 
risks to health described for the knee joint patellofemorotibial metal/
polymer porous-coated uncemented prosthesis and the knee joint 
femorotibial (uni-compartmental) metal/polymer porous-coated uncemented 
prosthesis. FDA agrees with the Panel that FDA recognized consensus 
standards and the FDA guidances are appropriate special controls to 
reasonably assure the safety and effectiveness of both devices. 
However, FDA disagrees with the Panel that postmarket surveillance is 
an appropriate special control to reasonably assure the safety and 
effectiveness of the knee joint femorotibial (uni-compartmental) metal/
polymer porous-coated uncemented prosthesis
    In their deliberations, the panel stated that it was important that 
adverse device outcomes be reported to FDA. The panel thought that 
adverse device outcomes should be tracked through postmarket 
surveillance. FDA agrees with the Panel that adverse device outcomes 
should be reported to FDA. However, FDA believes that another 
postmarket mechanism better addresses the Panel's concern that adverse 
device outcomes should be reported to FDA. FDA believes that the 
existing mandatory medical device reporting (MDR) system is the 
appropriate mechanism to report such adverse

[[Page 12018]]

events. Therefore, postmarket surveillance is unnecessary to address 
the Panel's concerns and to reasonably assure the safety and 
effectiveness of the device.
    Based on the available information, FDA identified the following 11 
FDA recognized American Society for Testing and Materials (ASTM) 
consensus standards and 4 FDA guidance documents as special controls to 
reasonably assure the safety and effectiveness of both devices:

A. ASTM Consensus Standards

    1. ``ASTM F 67-95, Standard Specifications for Unalloyed Titanium 
for Surgical Implants Applications'';
    2. ``ASTM F 75-98, Standard Specification for Cast Cobalt-28 
Chromium-6 Molybdenum Alloy for Surgical Implant Applications'';
    3. ``ASTM F 136-96, Standard Specification for Wrought Titanium-6 
Aluminum-4 Vanadium ELI (Extra Low Interstitial) Alloy (R56401) for 
Surgical Implant Application'';
    4. ``ASTM F 648-98, Standard Specification for Ultra-High-
Molecular-Weight Polyethylene Powder and Fabricated Form for Surgical 
Implants'';
    5. ``ASTM F 1044-95, Standard Test Method for Shear Testing of 
Porous Metal Coatings'';
    6. ``ASTM F 1147-95, Standard Test Method for Tension Testing of 
Porous Metal Coatings'';
    7. ``ASTM F 1160-91, Standard Test Method for Constant Stress 
Amplitude Fatigue Testing of Porous Metal-Coated Metallic Materials'';
    8. ``ASTM F 1377-98, Standard Specification for Cobalt-28 Chromium-
6 Vanadium Powder for Coating of Orthopedic Implants'';
    9. ``ASTM F 1580-98, Standard Specification for Titanium and 
Titanium-6% Aluminum-4% Vanadium Alloy Powders for Coatings of Surgical 
Implants'';
    10. ``ASTM F 1672-95, Standard Specification for Resurfacing 
Patellar Prosthesis''; and
    11. ``ASTM F 1800-97, Standard Test Method for Cyclic Fatigue 
Testing of Metal Tibial Tray Components of Total Knee Joint 
Replacements.''
    The ASTM standards define material specifications and testing 
methods for the knee joint patellofemorotibial metal/polymer porous-
coated uncemented prosthesis and the knee joint femorotibial (uni-
compartment) metal/polymer porous-coated uncemented prosthesis. 
Adherence to these standards and comparison of the results from these 
standard test methods can control the risks to health of adverse tissue 
reaction, pain and/or loss of function, and revision, by having the 
manufacturer use surgical implant quality materials and assuring that 
the device has acceptable performance through mechanical testing.
    ASTM standards may be obtained from ASTM Customer Services, 100 
Barr Harbor Dr., West Conshohocken, PA 19428, telephone 610-832-9585. 
ASTM has a site on the Internet at the address http://www.astm.org.

B. Guidance Documents

    1. ``Guidance for the Preparation of Premarket Notifications 
(510(k)s) for Cemented, Semi-Constrained Total Knee Prostheses.'' 
(Facts-on-Demand #830);
    2. ``Guidance Document for Testing Orthopedic Implants with 
Modified Metallic Surfaces Apposing Bone or Bone Cement.'' (Facts-on-
Demand #827);
    3. ``Guidance Document for Testing Non-articulating, Mechanically 
Locked' Modular Implant Components.'' (Facts-on-Demand #916); and
    4. ``Preparation of Premarket Notification (510(k)) Applications 
for Orthopedic Devices.'' (Facts-on-Demand #832).
    The FDA guidance documents provide guidance on how to meet general 
orthopedic device premarket notification (510(k)) requirements, 
including biocompatibility testing, sterility testing, mechanical 
performance testing, and physician and patient labeling for the knee 
joint patellofemorotibial metal/polymer porous-coated uncemented 
prosthesis and the knee joint femorotibial (uni-compartmental) metal/
polymer porous-coated uncemented prosthesis. Use of the pre-clinical 
section of the FDA guidance documents can control the risks to health 
of adverse tissue reaction, infection, pain and/or loss of function, 
and revision by having manufacturers use surgical quality implant 
materials, adequately test and sterilize their devices, and provide 
adequate directions for use and patient information.
    To receive a guidance via fax machine, telephone CDRH's Facts-on-
Demand (FOD) system at 800-899-0381 or 301-827-0111 from a touch-tone 
telephone. At the first voice prompt, press 1 to access DSMA Facts; at 
the second voice prompt, press 2, and then enter the document number 
(in parentheses in the list above) followed by the pound sign (#). Then 
follow the remaining voice prompts to compete your request.
    Persons interested in obtaining a copy of these guidances may also 
do so using the Internet. The Center for Devices and Radiological 
Health (CDRH) maintains an entry on the Internet for easy access to 
information including text, graphics, and files that may be downloaded 
to a personal computer with access to the Internet. The CDRH home page 
may be accessed at http://www.fda.gov/cdrh.

IX. FDA's Tentative Findings

    FDA believes that the knee joint patellofemorotibial metal/polymer 
porous-coated uncemented prosthesis and the knee joint femorotibial 
(uni-compartmental) metal/polymer porous-coated uncemented prosthesis 
should be reclassified into class II because special controls, in 
addition to general controls, would provide reasonable assurance of the 
safety and effectiveness of the devices, and there is sufficient 
information to establish special controls to provide such assurance.

X. References

    The following references have been placed on display in the Dockets 
Management Branch (address above) and may be seen by interested persons 
between 9 a.m. and 4 p.m.
    1. Petition for reclassification of the Patello-Femoro-Tibial 
Metal/Polymer/Metal Biologically Fixed Prosthesis submitted by the 
Orthopedic Surgical Manufacturers Association, July 28, 1997.
    2. Transcript of the Orthopedic and Rehabilitation Devices Panel 
Meeting, January 12 and 13, 1998, Vol. II, pp. 1 to 227.

XI. Environmental Impact

    The agency has determined under 21 CFR 25.34(b) that these 
reclassification actions do not individually or cumulatively have a 
significant effect on the human environment. Therefore, neither an 
environmental assessment nor an environmental impact statement is 
required.

XII. Analysis of Impacts

    FDA has examined the impacts of the notice under Executive Order 
12866 and the Regulatory Flexibility Act (Public Law 96-354) (as 
amended by subtitle D of the Small Business Regulatory Fairness Act of 
1996 (Public Law 104-121), and the Unfunded Mandates Reform Act of 1995 
(Public Law 104-4). Executive Order 12866 directs agencies to assess 
all costs and benefits of available regulatory alternatives and, when 
regulation is necessary, to select regulatory approaches that maximize 
net benefits (including potential economic, environmental, public 
health and safety and other advantages; distributive impacts; and 
equity). The agency believes that these reclassification actions are 
consistent

[[Page 12019]]

with the regulatory philosophy and principles identified in the 
Executive Order. In addition, the reclassification actions are not 
significant regulatory actions as defined by the Executive Order and so 
are not subject to review under the Executive Order.
    The Regulatory Flexibility Act requires agencies to analyze 
regulatory options that would minimize any significant impact of a rule 
on small entities. Reclassification of the devices from class III to 
class II will relieve manufacturers of the cost of complying with the 
premarket approval requirements in section 515 of the act. Because 
reclassification will reduce regulatory costs with respect to this 
device, it will impose no significant economic impact on any small 
entities, and it may permit small potential competitors to enter the 
marketplace by lowering their costs. The agency therefore certifies 
that these reclassification actions, if finalized, will not have a 
significant economic impact on a substantial number of small entities. 
In addition, this reclassification action will not impose costs of $100 
million or more on either the private sector or State, local, and 
tribal governments in the aggregate, and therefore a summary statement 
of analysis pursuant to section 202(a) of the Unfunded Mandates Reform 
Act of 1995 is not required.

XIII. Request for Comments

    Interested persons may, on or before June 7, 2000, submit to the 
Dockets Management Branch (address above) written comments regarding 
this document. Two copies of any comments are to be submitted, except 
that individuals may submit one copy. Comments are to be identified 
with the docket number found in brackets in the heading of this 
document. Received comments may be seen in the office above between 9 
a.m. and 4 p.m. Monday through Friday.

    Dated: February 14, 2000.
Linda S. Kahan,
Deputy Director for Policy, Center for Devices and Radiological Health.
[FR Doc. 00-5467 Filed 3-6-00; 8:45 am]
BILLING CODE 4160-01-F