[Federal Register Volume 64, Number 34 (Monday, February 22, 1999)]
[Notices]
[Pages 8579-8580]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-4213]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration
[Docket No. 99D-0186]


Draft Guidance for Industry on Testing Orthopedic Implants With 
Metallic Plasma Sprayed Coatings 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availability of a draft guidance entitled ``Guidance for Industry on 
Testing Orthopedic Implants With Metallic Plasma Sprayed Coatings to 
Support Reconsideration of Postmarket Surveillance Requirements.'' This 
draft guidance is neither final nor is it in effect at this time. 
Metallic plasma spray coatings, both porous and nonporous, 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 identifying a set of testing methods that 
will accurately compare the mechanical properties of metallic plasma 
spray coatings with the same properties of sintered or diffusion bonded 
porous coatings. This draft guidance document proposes to use a number 
of mechanical tests to compare the mechanical properties of the various 
types of coatings. CDRH needs the ability to make the above comparisons 
in order to identify coated hip devices that should be subject to 
postmarket surveillance requirements.

DATES: Written comments concerning this draft guidance document must be 
received by May 24, 1999.

ADDRESSES: Submit written requests for single copies on a 3.5'' 
diskette of the draft guidance document entitled ``Guidance for 
Industry on Testing Orthopedic Implants With Metallic Plasma Sprayed 
Coatings to Support Reconsideration of Postmarket Surveillance 
Requirements'' to the Division of Small Manufacturers Assistance (HFZ-
220), CDRH, 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written comments concerning this draft guidance document to the Dockets 
Management Branch (HFA-305), Food and Drug Administration, 5630 Fishers 
Lane, rm. 1061, Rockville, MD 20852. Comments should be identified with 
the docket number found in brackets in the heading of this document. 
See the SUPPLEMENTARY INFORMATION section for information on electronic 
access to the draft guidance.
 FOR FURTHER INFORMATION CONTACT: Anita M. Rayner, Center for Devices 
and Radiological Health (HFZ-543), Food and Drug Administration, 1350 
Piccard Dr., Rockville, MD 20850, 301-594-0006.

SUPPLEMENTARY INFORMATION:

I. Background

     FDA announced the reclassification and codification of the hip 
joint, metal/polymer/metal, semi-constrained, porous-coated uncemented 
prostheses 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 determined that hip 
prostheses using plasma sprayed porous coatings for

[[Page 8580]]

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 will consist of prospective, 
long-term, followup of a population of patients who have received a 
cementless implantation of the manufacturer's plasma sprayed porous 
coated hip prosthesis. The objective of the patient followup is 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 with 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 were used to 
produce only porous coatings. CDRH now also recognizes that hip 
prostheses with nonporous metallic coatings are also 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 released a draft guidance document describing 
testing methods that CDRH believed could compare the mechanical 
properties of plasma sprayed coatings with those of sintered and 
diffusion bonded porous coatings. Several comments on that draft 
guidance document were received. Some comments on that draft guidance 
document included mechanical test data on different thermal spray 
coatings, both porous and nonporous. 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 proposing to 
use the mechanical test methods described in this draft guidance 
document to reevaluate, on a case-by-case basis, the need for 
manufacturers to conduct postmarket surveillance of their metallic 
thermal spray coated hip prostheses.

II. Significance of Guidance

     This draft 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 Testing Orthopedic 
Implants With Metallic Plasma Sprayed Coatings 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 draft guidance may 
also do so using the World Wide Web (WWW). CDRH maintains an entry on 
the WWW for easy access to information including text, graphics, and 
files that may be downloaded to a personal computer with access to the 
WWW. Updated on a regular basis, the CDRH home page includes ``Guidance 
for Industry on Testing Orthopedic Implants With Metallic Plasma 
Sprayed Coatings 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 Testing Orthopedic 
Implants With Metallic Plasma Sprayed Coatings to Support 
Reconsideration of Postmarket Surveillance Requirements'' will be 
available at ``http://www.fda.gov/cdrh/postsurv''.

IV. Comments

    Interested persons may, on or before May 24, 1999, submit to 
Dockets Management Branch (address above) written comments regarding 
this draft guidance. 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. The guidance document and received comments may be seen 
in the Dockets Management Branch between 9 a.m. and 4 p.m., Monday 
through Friday.

    Dated: February 8, 1999.
 Linda S. Kahan,
 Deputy Director for Regulations Policy, Center for Devices and 
Radiological Health.
[FR Doc. 99-4213 Filed 2-19-99; 8:45 am]
BILLING CODE 4160-01-F