[Federal Register Volume 65, Number 22 (Wednesday, February 2, 2000)]
[Notices]
[Pages 4981-4982]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-2242]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. 99D-0186]


Medical Devices; Guidance for Industry on the Testing of Metallic 
Plasma Sprayed Coatings on Orthopedic Implants to Support 
Reconsideration of Postmarket Surveillance Requirements; Availability

AGENCY:  Food and Drug Administration, HHS.

ACTION:  Notice.

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SUMMARY:  The Food and Drug Administration (FDA) is announcing the 
availability of a guidance entitled ``Guidance for Industry on the 
Testing of Metallic Plasma Sprayed Coatings on Orthopedic Implants to 
Support Reconsideration of Postmarket Surveillance Requirements.'' This 
guidance is final and is in effect at this time. Metallic plasma spray 
coatings, both porous and non-porous, and metallic sintered or 
diffusion bonded porous coatings are used to attach artificial joints 
to living bone. FDA's Center for Devices and Radiological Health (CDRH) 
is issuing this guidance to identify a set of testing methods that can 
be used to accurately evaluate the mechanical properties of the various 
types of coatings. CDRH will use such data to identify which coated hip 
devices should remain subject to postmarket surveillance requirements.

DATES:  Submit written comments at any time.

ADDRESSES:  See the SUPPLEMENTARY INFORMATION section for information 
on electronic access to the guidance. Submit written requests for 
single copies on a 3.5" diskette of the guidance document entitled 
``Guidance for Industry on the Testing of Metallic Plasma Sprayed 
Coatings on Orthopedic Implants to Support Reconsideration of 
Postmarket Surveillance Requirements'' to the Division of Small 
Manufacturers Assistance (HFZ-220), Center for Devices and 
Radiological, Food and Drug Administration, 1350 Piccard Dr., 
Rockville, MD 20850. Send two self-addressed adhesive labels to assist 
that office in processing your request, or fax your request to 301-443-
8818. Submit written comments on this guidance document to David L. 
Daly (address below).

FOR FURTHER INFORMATION CONTACT:  David L. Daly, Center for Devices and 
Radiological Health (HFZ-510), Food and Drug Administration, 1350 
Piccard Dr., Rockville, MD 20850, 301-594-3674.

SUPPLEMENTARY INFORMATION:

I. Background

    On February 21, 1992, FDA sent a letter order to petitioner, 
Richards Medical Co., reclassifying the hip joint, metal/polymer/metal, 
semi-constrained, porous-coated uncemented prosthesis from class III 
(Premarket Approval) into class II (Special Controls). The 
reclassification was published in the Federal Register of January 8, 
1993 (58 FR 3227). The reclassification was effective February 21, 
1992. On February 15, 1994, CDRH's Orthopedic and Rehabilitation 
Devices Branch (ORDB) determined that hip prostheses using plasma 
sprayed porous coatings for biological fixation can be substantially 
equivalent to the reclassified porous coated hip prosthesis. As part of 
the decision, CDRH, using the then existing authority of section 
522(a)(1)(C) of the Federal Food, Drug, and Cosmetic Act, required 
manufacturers of plasma spray porous coated hip prostheses to conduct 
postmarket surveillance of their devices. Postmarket surveillance was 
required because of CDRH's concern that reported differences between 
the mechanical properties, particularly abrasion resistance, of plasma 
sprayed coatings and sintered and diffusion bonded porous coatings 
could have an adverse effect on the long-term revision rate of the 
plasma sprayed devices. While CDRH has clinical data describing the 
long-term revision rate of sintered and diffusion bonded porous coated 
hip prostheses, CDRH does not have this type of data on the cementless 
use of plasma sprayed hip prostheses. The postmarket surveillance 
consisted of prospective, long-term, followup of a population of 
patients who have received cementless implantation of the 
manufacturer's plasma sprayed porous coated hip prosthesis. The 
objective of the patient followup was to determine the long-term 
revision rate for each plasma sprayed porous coated hip prosthesis.
    At the time postmarket surveillance was required, CDRH believed 
that the term ``plasma spray'' was a single manufacturing technique 
that produced a single form of coating, having a single set of 
metallurgical and mechanical properties. CDRH now recognizes that 
plasma spray manufacturing methods are a subset of the larger ``thermal 
spray'' group of metallic coating production methods. CDRH has come to 
recognize that thermal spray coating methods can produce coatings with 
a wide range of metallurgical and mechanical properties. As an example, 
CDRH originally believed that, when used to apply metallic coatings to 
hip prostheses, plasma spray manufacturing techniques produced only 
porous coatings. CDRH now also recognizes that hip prostheses with non-
porous metallic coatings can be manufactured by plasma spray and other 
thermal spray methods.
    Several manufacturers, using a variety of thermal spray coating 
methods, have received substantial equivalence decisions for their 
coated hips. A number of these manufacturers have sought 
reconsideration of CDRH's decision to require postmarket surveillance 
of their products. Several of the requests for reconsideration are, in 
part, based on claims that manufacturing technology permits the 
production of plasma sprayed coatings with mechanical properties, 
particularly abrasion resistance, equal to or better than those of the 
sintered or diffusion bonded porous coatings upon which the 
reclassification was based. In response to the requests for 
reconsideration, CDRH, on February 22, 1999, reissued a draft guidance 
document describing testing methods that CDRH believed could measure 
the mechanical properties of plasma sprayed coatings. Several comments 
on the draft guidance document were received. CDRH has considered those 
comments and is now issuing this guidance as final guidance that is 
effective immediately.
    Some comments on the draft guidance document included mechanical 
test data on different thermal spray coatings, both porous and non-
porous. These data indicate that thermal spray coatings can have 
mechanical properties greater than, less than, or almost equal to those 
of sintered or diffusion bonded porous coatings. CDRH does not believe 
that postmarket surveillance is necessary for hip prostheses whose 
coatings have mechanical properties, particularly abrasion resistance, 
equal to or better than sintered or diffusion bonded porous coatings. 
As a result, CDRH is now inviting those manufacturers who have received 
postmarket surveillance orders to apply for reconsideration of those 
orders. CDRH will, on a case by case basis, reevaluate the need for 
manufacturers to conduct postmarket surveillance of their metallic 
thermal spray coated hip prostheses.

[[Page 4982]]

II. Significance of Guidance

    This guidance document represents the agency's current thinking on 
what data are necessary to support reconsideration of the thermal spray 
coated hip prosthesis postmarket surveillance requirements. It does not 
create or confer any rights for or on any person and does not operate 
to bind FDA or the public. An alternative approach may be used if such 
approach satisfies the applicable statute, regulations, or both.
    The agency has adopted Good Guidance Practices (GGP's), which set 
forth the agency's policies and procedures for the development, 
issuance, and use of guidance documents (62 FR 8961, February 27, 
1997). This guidance document is issued as a Level 1 guidance 
consistent with GGP's.

III. Electronic Access

    In order to receive ``Guidance for Industry on the Testing of 
Metallic Plasma Sprayed Coatings on Orthopedic Implants to Support 
Reconsideration of Postmarket Surveillance Requirements'' via your fax 
machine, call the CDRH 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 second voice prompt press 2, and then 
enter the document number (946) followed by the pound sign (#). Then 
follow the remaining voice prompts to complete your request.
    Persons interested in obtaining a copy of the guidance may also do 
so using the Internet. 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. Updated 
on a regular basis, the CDRH home page includes ``Guidance for Industry 
on the Testing of Metallic Plasma Sprayed Coatings on Orthopedic 
Implants to Support Reconsideration of Postmarket Surveillance 
Requirements,'' device safety alerts, Federal Register reprints, 
information on premarket submissions (including lists of approved 
applications and manufacturers' addresses), small manufacturers' 
assistance, information on video conferencing and electronic 
submissions, Mammography Matters, and other device-oriented 
information. The CDRH home page may be accessed at http://www.fda.gov/cdrh. ``Guidance for Industry on the Testing of Metallic Plasma Sprayed 
Coatings on Orthopedic Implants to Support Reconsideration of 
Postmarket Surveillance Requirements'' will be available at http://www.fda.gov/cdrh/postsurv/plasmaspry.pdf.

IV. Comments

    Interested persons may, at any time submit to the contact person 
above written comments regarding this guidance. FDA will consider any 
comments to determine whether to revise or revoke the guidance.

    Dated: January 16, 2000.
Linda S. Kahan,
Deputy Director for Regulations Policy, Center for Devices and 
Radiological Health.
[FR Doc. 00-2242 Filed 2-1-00; 8:45 am]
BILLING CODE 4160-01-F