Identity Imprint Cruciate Retaining (CR) Knee Replacement System and Identity Imprint Posterior Stabilized (PS) Knee Replacement System
K213389 · Conformis, Inc. · JWH · Nov 10, 2021 · Orthopedic
Device Facts
Record ID
K213389
Device Name
Identity Imprint Cruciate Retaining (CR) Knee Replacement System and Identity Imprint Posterior Stabilized (PS) Knee Replacement System
Applicant
Conformis, Inc.
Product Code
JWH · Orthopedic
Decision Date
Nov 10, 2021
Decision
SESE
Submission Type
Special
Regulation
21 CFR 888.3560
Device Class
Class 2
Attributes
Therapeutic
Indications for Use
The Identity Imprint CR Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis. The Indications for Use include: · Painful joint disease due to osteoarthritis, traumatoid arthritis or osteonecrosis of the knee. - · Post traumatic loss of joint function - · Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability. · Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants · Revision procedures provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans. This implant is intended for cemented use only. The Identity Imprint PS Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis. The Indications for Use include: · Painful joint disease due to osteoarthritis, traumatoid arthritis, polyarthritis, polyarthritis or osteonecrosis of the knee. · Post traumatic loss of joint function · Moderate varus, valgus or flexion deformity · Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartental implants · Revision procedures provided that the anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans. This implant is intended for cemented use only.
Device Story
Semi-constrained total knee replacement system; includes femoral, tibial, and patellar components. Uses patient imaging (CT/MR) to select standard implants matching patient anatomy. Provided with patient-specific and standard manual surgical instruments for intraoperative positioning and bone cutting. Used by surgeons in clinical settings. Benefits include restoration of joint function and pain relief. Subject submission specifically introduces alternate packaging (PETG trays with Tyvek lids) for standardized implants.
Clinical Evidence
No clinical data. Substantial equivalence supported by non-clinical performance evaluation of packaging configuration, including stability studies and risk assessments previously cleared in K192198.
Indicated for patients with knee joint pain/disability requiring total knee replacement due to osteoarthritis, traumatic/rheumatoid arthritis, osteonecrosis, post-traumatic loss of function, or failed prior implants (osteotomies, hemiarthroplasties, unicondylar/patellofemoral/bicompartmental). Suitable for moderate varus, valgus, or flexion deformity if ligamentous stability is achievable. Intended for cemented use only.
Regulatory Classification
Identification
A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented 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 alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).
Predicate Devices
Identity Imprint Knee Replacement System (K212411/K210191)
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November 10, 2021
Image /page/0/Picture/1 description: The image shows the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.
Conformis Inc. Kara Johnson Sr. Director, Regulatory Affairs 600 Technology Park Drive, 4th Floor Billerica, Massachusetts 01821
## Re: K213389
Trade/Device Name: Identity Imprint Cruciate Retaining (CR) Knee Replacement System, Identity Imprint Posterior Stabilized (PS) Knee Replacement System Regulation Number: 21 CFR 888.3560 Regulation Name: Knee Joint Patellofemorotibial Polymer Semi-Constrained Cemented Prosthesis Regulatory Class: Class II Product Code: JWH, OIY, OOG Dated: October 14, 2021 Received: October 15, 2021
Dear Kara Johnson:
We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.
If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.
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Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/combination-products/guidance-regulatory-information/postmarketing-safety-reportingcombination-products); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-
542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to https://www.fda.gov/medical-device-safety/medical-device-reportingmdr-how-report-medical-device-problems.
For comprehensive regulatory information about medical devices and radiation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/medicaldevices/device-advice-comprehensive-regulatory-assistance) and CDRH Learn (https://www.fda.gov/training-and-continuing-education/cdrh-learn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (https://www.fda.gov/medical-device-advice-comprehensive-regulatoryassistance/contact-us-division-industry-and-consumer-education-dice) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely.
Ting Song, Ph.D., R.A.C. Assistant Director DHT6A: Division of Joint Arthroplasty Devices OHT6: Office of Orthopedic Devices Office of Product Evaluation and Quality Center for Devices and Radiological Health
Enclosure
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## Indications for Use
510(k) Number (if known) K213389
#### Device Name
Identity Imprint Knee Replacement System (including Identity Imprint Posterior Stabilized (PS) KRS and Identity Imprint Cruciate Retaining (CR) KRS)
# Indications for Use (Describe)
Identity Imprint CR KRS
The Identity Imprint CR Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
· Painful joint disease due to osteoarthritis, traumatoid arthritis or osteonecrosis of the knee.
- · Post traumatic loss of joint function
- · Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.
· Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants
· Revision procedures provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
This implant is intended for cemented use only.
Identity Imprint PS KRS
The Identity Imprint PS Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
· Painful joint disease due to osteoarthritis, traumatoid arthritis, polyarthritis, polyarthritis or osteonecrosis of the knee.
· Post traumatic loss of joint function
· Moderate varus, valgus or flexion deformity
· Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartental implants
· Revision procedures provided that the anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
This implant is intended for cemented use only.
Type of Use (Select one or both, as applicable)
X Prescription Use (Part 21 CFR 801 Subpart D)
Over-The-Counter Use (21 CFR 801 Subpart C)
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Image /page/4/Picture/1 description: The image shows the logo for Conformis. The logo consists of the word "CONFORMIS" in a sans-serif font. The letters "CONF" are in black, while the letters "ORMIS" are in orange. Above the word is a stylized "C" shape, with the top half in orange and the bottom half in black.
## 510(k) SUMMARY
| Submitter's Name and Address: | Conformis, Inc.<br>600 Technology Park Drive<br>Billerica, MA 01821 |
|---------------------------------------|------------------------------------------------------------------------------------------------------------------|
| Establishment Registration Number(s): | 3009844603 and 3004153240 |
| Date Summary was Prepared: | October 27, 2021 |
| Contact Person: | Kara Johnson<br>Sr. Director, Regulatory Affairs<br>Telephone: 781-832-5402<br>Email: kara.johnson@conformis.com |
#### Trade/Device Name(s):
Identity Imprint Knee Replacement System (including Identity Imprint Posterior Stabilized (PS) KRS and Identity Imprint Cruciate Retaining (CR) KRS)
#### Common Name:
Knee Replacement System
Device Class: Class II
# Regulation Numbers:
888.3560
#### Classification Names and Product Codes:
Prosthesis, Knee, Patellofemorotibial, Semi-Constrained, Cemented, Polymer/Metal/PolymerKnee Arthroplasty Implantation System; JWH, OIY, OOG
# Legally Marketed Predicate Device
#### (Primary Predicate):
Identity Imprint Knee Replacement System (including Identity Imprint Posterior Stabilized (PS) KRS and Identity Imprint Cruciate Retaining (CR) KRS (K212411/K210191)
#### (Secondary Predicates):
Conformis iTotal Hip Replacement System (K192198)
#### Device Description:
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Image /page/5/Picture/1 description: The image shows the logo for Conformis. The logo consists of a stylized letter "C" in orange and black, with the word "CONFORMIS" written in black and orange below it. The "O", "R", "M", and "I" in "CONFORMIS" are in orange, while the rest of the letters are in black.
The subject device. Identity Imprint Knee Replacement System, is a knee replacement system including standardized implant sizes combined with standard and patient-specific ancillary surgical instrumentation. As with all Conformis Knee Replacement Systems (KRS), the Identity Imprint Knee Replacement System is semi-constrained knee implants which consist of a femoral, tibial, and/or patellar components. The products are intended for treatment of severe pain and/or disability of the knee damaged by osteoarthritis or trauma.
Using patient imaging (either CT or MR scans), a standard implant is selected that best meets the geometric and anatomic requirements of the specific patient. The femoral components of the subject devices are manufactured from cobalt chromium molybdenum (CoCrMo) alloy. The tibial component includes a metal tray manufactured from titanium alloy and polyethylene inserts. The patellar components are manufactured from UHMWPE.
For user convenience, single-use, standard and patient-specific ancillary orthopedic manual surgical instruments designed for use with the selected Identity Imprint implants are provided to assist in the positioning of the total knee replacement components intraoperatively and in guiding the cutting of bone. In addition, reusable orthopedic manual surgical instruments are provided separately.
# Indications for Use: Identity Imprint CR KRS
The Identity Imprint CR Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
- Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis or osteonecrosis of the knee.
- Post traumatic loss of joint function .
- Moderate varus, valgus, or flexion deformity in which the ligamentous structures can ● be returned to adequate function and stability.
- . Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants
- . Revision procedures provided that anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
This implant is intended for cemented use only.
# Identity Imprint PS KRS
The Identity Imprint PS Knee Replacement System is intended for use as a total knee replacement in patients with knee joint pain and disability whose conditions cannot be solely addressed by the use of a prosthetic device that treats only one or two of the three knee compartments, such as unicondylar, patellofemoral or bicompartmental prosthesis.
The Indications for Use include:
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Image /page/6/Picture/1 description: The image shows the logo for Conformis. The logo consists of a stylized letter "C" in orange and black, with the word "CONFORMIS" written in black and orange letters below it. The letters "FORMI" are in orange, while the rest of the word is in black.
- Painful joint disease due to osteoarthritis, traumatic arthritis, rheumatoid arthritis, polyarthritis or osteonecrosis of the knee.
- . Post traumatic loss of joint function
- Moderate varus, valgus or flexion deformity
- . Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartental implants
- Revision procedures provided that the anatomic landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.
This implant is intended for cemented use only.
## Technological Characteristics:
The subject device single-use, disposable patient-specific instrumentation, implants, and reusable instruments remain identical to the predicate device in operating principle, fundamental technology, design, materials, and manufacturing methods. This submission seeks clearance for additional packaging configuration options for use with the Identity Imprint Knee Replacement System (including Identity Imprint Posterior Stabilized (PS) KRS and Identity Imprint Cruciate Retaining (CR) KRS) (K212411). Specifically. this submission seeks clearance to use PETG trays with Tyvek lids as an alternate packaging configuration for the standardized implants sterilized via Ethylene Oxide. The PETG trays with Tyvek lids were cleared for use with the Conformis Hip System in K192198.
#### Non-Clinical Performance Evaluation:
The proposed packaging configuration has been previously verified/validated and cleared for use with the Conformis iTotal Hip Replacement System (K192198). A rationale (TD-04858) for the proposed packaging configuration for use with the Identity Imprint Knee Replacement System summarizes packaging design testing, applicable stability studies, and risk assessments/rationale. This rationale supports that the proposed packaging configuration for use with the subject device are as safe, effective, and perform as well or better than the predicate device(s) packaging configuration. No new issues of safety or efficacy were raised.
#### Conclusion:
Based on a comparison of the intended use and technological characteristics to the predicate device(s) and on the results of the packaging Performance Evaluation it is concluded that the proposed Identity Imprint KRS is substantially equivalent.
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