The iTotal Identity Cruciate Retaining (CR) Knee Replacement System (KRS) 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 compartments, such as a 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 finction and stability.
Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants.
Revision procedures provided that analy landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.

This implant is for cemented use only.

The iTotal PS Knee Replacement System (KRS) is intended for use as a total knee replacement in patients with knee joint I rie 1 olar 1 5 Kince Replacement be solely addressed by the use of a prosthetic device that treats only one or two of the three compartments, such as a 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 bicompartmental implants.
Revision procedures provided that and only landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.

Device Description

iTotal Identity® Cruciate Retaining (CR) Knee Replacement System (KRS) and iTotal Identity® Posterior Stabilized (PS) Knee Replacement System (KRS) are patient specific tri-compartmental faceted knee replacements systems. The iTotal Identity CR KRS is a faceted posterior cruciate ligament retaining knee replacement system. It is a semi-constrained, cemented knee implant which consists of femoral, tibial, and patellar components. iTotal Identity® PS KRS is a semi-constrained, cemented knee implant consisting of femoral, tibial, patellar and articular tibial insert components.

Using patient imaging and a combination of proprietary and off-the-shelf software, a patient-specific implant is designed that best meets the geometric and anatomic requirements of the specific patient. The femoral component is manufactured from cobalt chromium molybdenum (CoCrMo) alloy. The tibial component includes a metal tray and tray keel stem extension manufactured from titanium (Ti6AL4V-ELI) alloy, a tibial tray keel (stem) cap manufactured from polyethylene (UHMWPE) and either one or two polyethylene inserts (Two piece is available with the CR KRS only). The polyethylene inserts may be manufactured from either UHMWPE (iPoly®) or iPoly® XE (a highly cross-linked vitamin E stabilized UHMWPE). The patellar component is provided in either a round or oval dome shape and may be manufactured from either UHMWPE or iPoly® XE.

For user convenience, single-use, patient-specific ancillary orthopedic manual surgical instruments designed for use with the proposed iTotal Identity® CR KRS or iTotal Identity® PS KRS 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.

AI/ML Overview

This document describes the 510(k) clearance for the iTotal Identity® Cruciate Retaining (CR) Knee Replacement System and iTotal Identity® Posterior Stabilized (PS) Knee Replacement System. This clearance specifically focuses on adding an additional sterilization process (Vaporized Hydrogen Peroxide Low-Temperature Sterilant-Vacuum (VHP LTS-V)) to the existing approved methods. No device modifications were made.

Therefore, the acceptance criteria and study proving the device meets these criteria relate to the sterilization process and its impact on the safety and effectiveness of the device, rather than the device's functional performance as a knee replacement system itself.

Here's the breakdown of the information requested, based on the provided text:

1. A table of acceptance criteria and the reported device performance

Acceptance Criteria	Reported Device Performance
Sterilization Validation (Sterility Assurance Level)	Established a Sterility Assurance Level (SAL) of 1x10⁻⁶ using VHP LTS-V.
VHP Residual Testing	Not explicitly stated what the acceptance criteria were for residuals, but the "testing results conclude that the addition of the use of VHP LTS-V sterilization raises no new issues regarding safety or effectiveness." This implies residuals were within acceptable limits.
Biocompatibility	Risk-based biocompatibility testing was performed. The testing results conclude that the addition of the use of VHP LTS-V sterilization raises no new issues regarding safety or effectiveness.
Equivalence to Predicate	The VHP LTS-V sterilized subject devices were shown to be equivalent to the primary predicate devices using currently cleared sterilization processes (EO, VHP gas plasma). No new issues of safety and effectiveness were raised.

2. Sample size used for the test set and the data provenance

Sample Size: The document does not specify the exact sample sizes used for sterilization validation (e.g., number of devices or sterilization cycles). Sterilization validation typically involves a statistically determined number of units.
Data Provenance: The document does not explicitly state the country of origin or whether the data was retrospective or prospective. Given that this is a 510(k) submission for a medical device, the testing would be conducted post-development and pre-market, implying prospective testing specific to the sterilization method change.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

This type of information is not applicable to this submission. The "ground truth" here is objective scientific measurement (e.g., microbial load reduction for SAL, chemical residue levels for VHP residuals, biological response for biocompatibility). These are established through standardized testing protocols, not through expert consensus on images or clinical outcomes.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This is not applicable. Adjudication methods like 2+1 or 3+1 refer to a process where multiple human readers assess data (e.g., medical images) and their disagreements are resolved by an independent expert. This submission concerns engineering and material testing for sterilization, not human interpretation of clinical data.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This is not applicable. This submission is for enabling an additional sterilization process for an existing knee replacement system. It does not involve AI, human readers, or image interpretation.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This is not applicable. This is not an algorithm or software submission; it's a submission for a physical medical device and its manufacturing/sterilization process.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

The "ground truth" for this sterile medical device submission is based on scientific and engineering measurements from validated laboratory testing. This includes:

Microbiological testing: To establish Sterility Assurance Level (SAL) (e.g., bioburden testing, overkill methods, half-cycle testing).
Chemical analysis: To measure residual levels of the sterilant.
Biological assays: For biocompatibility testing to ensure the sterilized material does not elicit an adverse biological response.

8. The sample size for the training set

This is not applicable. A "training set" refers to data used to train machine learning models. This submission is for a physical medical device and its sterilization process, not an AI/ML product.

9. How the ground truth for the training set was established

This is not applicable for the same reason as above.

Summary

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February 17, 2021

Image /page/0/Picture/1 description: The image contains 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 square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

Conformis Inc. Mary Kruitwagen Sr. Regulatory Affairs Specialist 600 Technology Park Drive, 4th Floor Billerica. Massachusetts 01821

Re: K210252

Trade/Device Name: iTotal Identity® Cruciate Retaining (CR) Knee Replacement System, iTotal Identity® Posterior Stabilizing (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: January 25, 2021 Received: January 29, 2021

Dear Mary Kruitwagen:

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.

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

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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 Ouality Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known)

Device Name

iTotal Identity Cruciate Retaining (CR) Knee Replacement System

Indications for Use (Describe)

The iTotal Identity Cruciate Retaining (CR) Knee Replacement System (KRS) 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 replatent in pations with rate join of the three compartments, such as a 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 finction and stability.
Failed osteotomies, hemiarthroplasties, and unicondylar, patellofemoral or bicompartmental implants.
Revision procedures provided that analy landmarks necessary for alignment and positioning of the implant are identifiable on patient imaging scans.

This implant is for cemented use only.

Type of Use (Select one or both, as applicable)
Prescription Use (Part 21 CFR 801 Subpart D)
	Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the i ne burden instructions, search existing data sources, gather and maintain the data needed and complete tirrie to review instruction. Send comments regarding this burden estimate or any other aspect aft this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

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Indications for Use

510(k) Number (if known)

Device Name

iTotal Identity Posterior Stabilizing (PS) Knee Replacement System

Indications for Use (Describe)

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 bicompartmental implants.
Revision procedures provided that and only landmarks necessary for alignment and positioning of the implant are

identifiable on patient imaging scans.

Type of Use (Select one or both, as applicable)

Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use (21 CFR 801 Subpart C)

CONTINUE ON A SEPARATE PAGE IF NEEDED.

This section applies only to requirements of the Paperwork Reduction Act of 1995.

DO NOT SEND YOUR COMPLETED FORM TO THE PRA STAFF EMAIL ADDRESS BELOW.

The burden time for this collection of information is estimated to average 79 hours per response, including the I he burden instructions, search existing data sources, gather and maintain the data needed and complete time to review instruction. Send comments regarding this burden estimate or any other aspect of this information collection, including suggestions for reducing this burden, to:

Department of Health and Human Services Food and Drug Administration Office of Chief Information Officer Paperwork Reduction Act (PRA) Staff PRAStaff(@fda.hhs.gov

"An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB number."

page 350 of 127

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510(K) Summary

Subject Device: (Proprietary/Tradename):	iTotal Identity® Cruciate Retaining (CR) Knee Replacement SystemiTotal Identity® Posterior Stabilized (PS) Knee ReplacementSystem
Common Usual Name:	Knee Replacement System
Type of Submission:	Special 510(k)
Device Class:	II
Regulation Number:	888.3560
Regulation Description:	Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Primary Product Classification(Product Code) and Description:	JWHKnee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Secondary Product Classifications(Product Code) and Descriptions:	OOG, OIYKnee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Reviewing Agency:	Orthopedics
Date of Summary Preparation:	January 27, 2021
Submitter's Name and Address:	Conformis Inc.600 Technology Park DriveFourth FloorBillerica, MA 01821USA
Telephone Number:	781-345-9001
Establishment RegistrationNumber(s):	30098446033004153240
Contact Name:	Mary Kruitwagen
Contact Telephone:	781-345-9038
Contact email:	Mary.Kruitwagen@conformis.com
Alternate Contact:	Kara Johnson
Alternate Contact Telephone:	781-832-5402
Alternate Contact email:	Kara.Johnson@conformis.com
Primary Predicate Device:	iTotal Identity® Cruciate Retaining (CR) Knee Replacement SystemiTotal Identity® Posterior Stabilized (PS) Knee ReplacementSystem
Primary Predicate Device 510(k):	K203447; December 22, 2020
Primary Predicate Device ProductClassification (ProCode) andDescription:	JWH, OOG, OIYKnee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Secondary Predicate Device:	iUni Unicondylar Knee Replacement System, iDuoBicompartmental Knee Repair System, iTotal CR KneeReplacement System, iTotal PS Knee Replacement System
Secondary Predicate Device 510(k):	K193105; March 13, 2020
Secondary Predicate DeviceClassification (ProCode) andDescription:	JWH, OOG, OIY, NPJ, HSXKnee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Modification	This submission is to seek clearance for use of an additional sterilization processfor the subject devices iTotal Identity® Cruciate Retaining (CR) KneeReplacement System and iTotal Identity® Posterior Stabilized (PS) KneeReplacement System. This submission seeks to add Vaporized HydrogenPeroxide Low-Temperature Sterilant-Vacuum (VHP LTS-V) to the portfolio ofsterilization processes for the subject devices. There are no devicemodifications.
Device Description	iTotal Identity® Cruciate Retaining (CR) Knee Replacement System (KRS) andiTotal Identity® Posterior Stabilized (PS) Knee Replacement System (KRS) arepatient specific tri-compartmental faceted knee replacements systems. TheiTotal Identity CR KRS is a faceted posterior cruciate ligament retaining kneereplacement system. It is a semi-constrained, cemented knee implant whichconsists of femoral, tibial, and patellar components. iTotal Identity® PS KRS is asemi-constrained, cemented knee implant consisting of femoral, tibial, patellarand articular tibial insert components.Using patient imaging and a combination of proprietary and off-the-shelfsoftware, a patient-specific implant is designed that best meets the geometricand anatomic requirements of the specific patient. The femoral component ismanufactured from cobalt chromium molybdenum (CoCrMo) alloy. The tibialcomponent includes a metal tray and tray keel stem extension manufacturedfrom titanium (Ti6AL4V-ELI) alloy, a tibial tray keel (stem) cap manufacturedfrom polyethylene (UHMWPE) and either one or two polyethylene inserts (Twopiece is available with the CR KRS only). The polyethylene inserts may bemanufactured from either UHMWPE (iPoly®) or iPoly® XE (a highly cross-linkedvitamin E stabilized UHMWPE). The patellar component is provided in either around or oval dome shape and may be manufactured from either UHMWPE oriPoly® XE.For user convenience, single-use, patient-specific ancillary orthopedic manualsurgical instruments designed for use with the proposed iTotal Identity® CR KRSor iTotal Identity® PS KRS are provided to assist in the positioning of the totalknee replacement components intraoperatively and in guiding the cutting ofbone. In addition, reusable orthopedic manual surgical instruments areprovided separately.
Indications for Use	iTotal Identity® Cruciate Retaining (CR) Knee Replacement SystemThe iTotal Identity® Cruciate Retaining (CR) Knee Replacement System (KRS) isintended for use as a total knee replacement in patients with knee joint pain

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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 a 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.

iTotal Identity® Posterior Stabilized (PS) Knee Replacement System

The iTotal PS Knee Replacement System (KRS) 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 a unicondylar, patellofemoral or bicompartmental prosthesis.

The Indications for Use include:

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 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.

Technological Characteristics

The proposed and predicate devices are cemented knee implants that consist of three primary components; femoral, tibial, and patellar implants. Single-use, patient-specific ancillary surgical instruments are provided for use to assist with surgical implantation. Reusable ancillary surgical instruments, provided in a reusable instrument tray, assist with surgical implantation.

The subject devices iTotal Identity Cruciate Retaining (CR) Knee Replacement System and iTotal Identity® Posterior Stabilized (PS) Knee Replacement System are the same as the predicate devices with regards to:

Indications for Use
Device design

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Device usage Operating principles Packaging Sterilization processes (methods) Biocompatibility Shelf-life Materials of composition The modification is to add an additional sterilization process (method) for the subject devices. There are no design changes to the subject device beyond the added sterilization process. The manufacture of the subject device is unchanged from that described in the 510(k) submissions of the predicate devices.
Performance Data	Non-clinical testing was performed including sterilization and risk-based biocompatibility testing. The results support that the device components are effectively sterilized using VHP LTS-V. Testing includes: Sterilization Validation testing to establish a SAL of 1x10-6 VHP Residual Testing
	The testing results conclude that the addition of the use of VHP LTS-V sterilization raises no new issues regarding safety or effectiveness. The performance of the subject devices sterilized by VHP LTS-V is expected to be the same as the currently marketed predicate devices.
SubstantialEquivalence	The modification to add an additional sterilization process shows equivalency to the VHP LTS-V sterilization as described in the secondary predicate. Results support that the VHP LTS-V sterilized subject devices would be equivalent to the primary predicate devices using currently cleared sterilization processes (EO, VHP gas plasma). No new issues of safety and effectiveness were raised.
Conclusion	Based on the results of the testing performed, the subject iTotal Identity® Cruciate Retaining (CR) Knee Replacement System and iTotal Identity® Posterior Stabilized (PS) Knee Replacement System, are substantially equivalent to the predicate devices iTotal Identity® Cruciate Retaining (CR) Knee Replacement System and iTotal Identity® Posterior Stabilized (PS) Knee Replacement System and can be sterilized to a SAL of 1x10-6 utilizing VHP LTS-V sterilization.

Regulation Number and Section

§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.

(a)
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).(b)
Classification. Class II.