The iTotal® 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 a unicondylar, patello-femoral or bi-compartmental 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, hemiarthoplasties, and unicondylar, patello-femoral or bi-compartmental implants. The iTotal® CR Knee Replacement System is intended for cemented use only.

Device Description

The proposed iTotal CR Knee Replacement System (hereafter referred to as the "iTotal CR KRS") is a patient specific tri- compartmental faceted posterior cruciate ligament (PCL) retaining knee replacement system.. The iTotal CR KRS is a semi-constrained cemented knee implant which consists of a femoral, tibial and patellar component. The product design incorporates a bone preserving approach with minimal bone resection of the tibia and femur for the treatment of severe pain and/or disability of a knee damaged by osteoarthritis or trauma. Using patient imaging (either CT or MR scans), a patient-specific implant is designed that best meets the geometric and anatomic requirements of the specific patient. The device is manufactured from cobalt chromium molybdenum ("CoCrMo") alloy. The tibial component includes a metal tray manufactured from CoCrMo alloy and either one or two polyethylene inserts manufactured from UHMWPE of identical configuration. The patellar component is manufactured from UHMWPE.

AI/ML Overview

The ConforMIS iTotal® Cruciate Retaining (CR) Knee Replacement System received 510(k) clearance based on demonstrating substantial equivalence to predicate devices through non-clinical laboratory testing. No clinical studies or human-in-the-loop performance studies were performed to establish acceptance criteria or device performance in a clinical setting.

Here's a breakdown of the information provided:

1. Table of Acceptance Criteria and Reported Device Performance

Since this is a 510(k) submission based on substantial equivalence and non-clinical testing, there isn't a direct "acceptance criteria" table with specific performance metrics and reported values in the way one might see for an AI algorithm or a diagnostic device. Instead, the acceptance was based on the device meeting the performance objectives of a series of bench tests, indicating it performed as safely and effectively as legally marketed predicate devices. The document states: "Non-clinical laboratory testing was performed demonstrating that the device is safe and can be considered substantially equivalent to the predicate devices for the proposed intended use." and "Results of the bench testing conducted demonstrate that the iTotal KRS is substantially equivalent to the Predicate Knee Systems."

The types of testing performed, which serve as the implicit "acceptance criteria" by demonstrating equivalence, include:

Test Performed	Implied Acceptance Criteria / Objective	Reported Device Performance
Femoral Fatigue Testing	Demonstrate adequate fatigue life and strength of the femoral component, comparable to predicate devices.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Kinematic Range of Motion Testing	Demonstrate functional range of motion consistent with predicate devices and expected physiological movement.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Stability Characteristics Testing	Demonstrate satisfactory stability of the knee replacement system.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Patello-Femoral Lateral Stability Testing	Demonstrate adequate lateral stability of the patello-femoral articulation.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Contact Area and Surface Stress for the Patello-Femoral Articulation testing	Demonstrate acceptable contact mechanics (area and stress) in the patello-femoral joint.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Tibial-Femoral Contact Areas and Stress Testing	Demonstrate acceptable contact mechanics (area and stress) in the tibial-femoral joint.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
Modular Assembly and Disassembly Characteristics of the iTotal Tibial Plateau Testing	Demonstrate proper and secure assembly/disassembly of modular components.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.
UHMWPE Characterization	Characterize the material properties of the Ultra-High Molecular Weight Polyethylene (UHMWPE) components, ensuring they meet specifications.	Results are not explicitly quantified in the provided text, but the overall conclusion is that the testing demonstrated substantial equivalence to predicate devices.

2. Sample Size Used for the Test Set and Data Provenance

This submission is for a medical device (knee replacement system) and relies on non-clinical bench testing, not a test set of patient data/images. Therefore, the concepts of "sample size for the test set" and "data provenance" (country of origin, retrospective/prospective) are not applicable in this context. The "samples" would refer to the physical devices or components subjected to laboratory testing.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

Not applicable. There was no "ground truth" expert review of a test set as this was a physical device, not a diagnostic or AI-driven system.

4. Adjudication Method for the Test Set

Not applicable. There was no test set requiring adjudication in the context of this device submission.

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

Not applicable. This is not an AI-assisted diagnostic device, nor was an MRMC study conducted.

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

Not applicable. This is a physical knee replacement device, not an algorithm.

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

Not applicable in the typical sense for a diagnostic device. The "ground truth" for this device's safety and performance was established through engineering principles, material science, and mechanical testing standards relevant to orthopedic implants. The performance was compared to established predicate devices using these physical and mechanical tests.

8. The Sample Size for the Training Set

Not applicable. This device is not an AI algorithm and does not have a "training set."

9. How the Ground Truth for the Training Set was Established

Not applicable. As there is no training set for an AI algorithm.

Summary

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K094050 #1/5

5.0 510(k) SUMMARY

SEP 1 3 2010

This 510(k) Summary for the ConforMIS iTotal® Cruciate Retaining (CR) Knee Replacement System is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92.

Submitter's Name and Address:	ConforMIS Inc.2 Fourth Ave.Burlington, MA 01804
Contact Person:	Amita S. Shah, Director, Quality Assurance and Regulatory Affairs
Date:	December 29, 2009
Name of Medical Device:	Device Regulation: 21 CFR 888.3560Product Code: OR (87) JWH, Knee joint patellofemorotibialpolymer/metal/polymer semi-constrained cemented prosthesisCommon/Usual Name: Cruciate Retaining Total Knee Replacement SystemProprietary Name: ConforMIS iTotal Cruciate Retaining Knee Replacement System
Device Classification:	Class II
Indications for Use:	The iTotal® 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 a unicondylar, patello-femoral or bi-compartmental 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, hemiarthoplasties, and unicondylar, patello-femoral or bi-compartmental implants. The iTotal® CR Knee Replacement System is intended for cemented use only.
Device Description:	The proposed iTotal CR Knee Replacement System (hereafterreferred to as the "iTotal CR KRS") is a patient specific tri-compartmental faceted posterior cruciate ligament (PCL) retainingknee replacement system.. The iTotal CR KRS is a semi-constrainedcemented knee implant which consists of a femoral, tibial andpatellar component. The product design incorporates a bonepreserving approach with minimal bone resection of the tibia andfemur for the treatment of severe pain and/or disability of a kneedamaged by osteoarthritis or trauma.
	Using patient imaging (either CT or MR scans), a patient-specificimplant is designed that best meets the geometric and anatomicrequirements of the specific patient. The device is manufacturedfrom cobalt chromium molybdenum ("CoCrMo") alloy. The tibialcomponent includes a metal tray manufactured from CoCrMo alloyand either one or two polyethylene inserts manufactured fromUHMWPE of identical configuration. The patellar component ismanufactured from UHMWPE.
Substantial Equivalence:	The product subject of this premarket notification is substantiallyequivalent to the ConforMIS Tri-Compartmental Resurfacing (tCR)device (K052687), the Stryker Triathlon CR Total Knee System(K040267) and the Smith & Nephew Journey Bicruciate StabilizedKnee System (K042515) all of which are cemented total kneereplacement systems. See Table 5-1 below for a more detailedcomparison.

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K094050 #2/5

510(k) SUMMARY

Table 5-1: Comparison of the Proposed iTotal CR KRS and Predicate Knee Systems

Feature	Proposed DeviceiTotal CR KneeReplacement System	Predicate DeviceConforMISTri-CompartmentalResurfacing(tCR) device(K052687)	Predicate DeviceStryker TriathlonCR Total KneeSystem(K040267)	Predicate DeviceJourney BicruciateStabilized Knee System(K042515)
Indications forUse	The iTotal® CR KneeReplacement System isintended for use as a total	The ConforMISInc., Tri-Compartmental	The Triathlon CR TotalKnee System consists offemoral component, tibial	Total knee components areindicated for rheumatoid arthritis;post-traumatic arthritis,
knee replacement inpatients with knee jointpain and disability whoseconditions cannot be solelyaddressed by the use of aprosthetic device thattreats only one or two ofthe three kneecompartments, such as aunicondylar, patellofemoralor bi-compartmentalprosthesis. The indicationsfor use include:Painful joint diseasedue to osteoarthritis,traumatic arthritis orrheumatoid arthritisor osteonecrosis ofthe knee Post traumatic loss ofjoint function. Moderate varus,valgus or flexiondeformity in whichthe ligamentousstructures can bereturned to adequatefunction and stability Failed osteotomies,hemiarthoplasties,unicondylar,patellofemoral orbicompartmentalimplants. The iTotal® CR KneeReplacement System isintended for cemented useonly.	Resurfacing (ICR)Device is intendedfor use in patientswith severe kneejoint pain anddisability. Theindication for useinclude:Painful jointdisease duetoosteoarthritis, traumaticarthritis orrheumatoidarthritis of theknee Posttraumatic lossof jointfunction Valgus orvarusdeformity ofthe knee The ConforMIS Tri-compartmentalResurfacing (tCR)device is intendedfor use only withbone cement.	insert, and allpolyethylene patellarcomponents that areintended to be used withpreviously clearedTriathlon PrimaryCemented Tibial Tray inprimary or revision totalknee arthroplasty. TheTriathlon All PolyethylenePatellar components areintended to be used withfemoral components ofthe previously releasedDuracon Total KneeSystem, as well as thepreviously releasedTriathlon PS femoralcomponent in situationswhere replacement of thearticular surface of thepatella is required. TheTriathlon CR Total KneeSystem is intended toaccommodate theposterior cruciate ligament(PCL) if it is present.Specific indication andcontraindications arelisted belowIndications:Painful, disablingjoint disease of theknee resulting from:non inflammatorydegenerative jointdisease (includingosteoarthritis,traumatic arthritis oravascular necrosis)or rheumatoidarthritis Post- traumatic lossof knee jointconfiguration andfunction Moderate varus,valgus or flexiondeformity in whichthe ligamentousstructures can bereturned to adequatefunction andstability. Revision of previousunsuccessful kneereplacement or otherprocedure	osteoarthritis, or degenerativearthritis in older patients whoseage, weight, and activity level arecompatible with an adequate long-term result: failed osteotomies,unicompartmental replacement, ortotal knee replacement. Posteriorstabilized knee systems aredesigned for use in patients inprimary and revision surgery,where the anterior and posteriorcruciate are absent orincompetent and collateralligaments remain intact. Smith &Nephew, Inc., High PerformanceKnee components are indicatedfor use only with cement and aresingle use devices.

			femur and/orproximal tibia thatcannot be stabilizedby standard fracturemanagementtechniques.
Intended forCement use only	Yes	Yes	Yes	Yes
Components	• Femoral Component• Tibial Implant• Metal backed tibialcomponent• Patellar component	• FemoralComponent• Tibial Implant• All Polytibialcomponent• Patellarcomponent	• Femoral Component• Tibial Implant• Metal backedtibialcomponent• Patellar component	• Femoral Component• Tibial Implant• Metal backed tibialcomponent• Patellar component
Materials	• Femoral Implant-CoCrMo• Metal-Backed TibialComponents:• Tibial tray-CoCrMo• Tibial Inserts-UHMWPE• All Polymer PatellarComponent-(UHMWPE)	• FemoralImplant-CoCrMo• All poly tibiacomponent-UHMWPE• All PolymerPatellarComponent-(UHMWPE	• Femoral Implant-CoCrMo• Metal-Backed TibialComponents:• Tibial tray* -CoCrMo• Tibial Insert-UHMWPE withCoCrMolocking wire• All Polymer PatellarComponent-(UHMWPE)	• Femoral Implant- OxidizedZirconium• Metal-Backed TibialComponents:• Tibial tray- CoCrMo• Tibial Insert-UHMWPE• All Polymer PatellarComponent-(UHMWPE)
Design	Knee jointpatellofemorotibial semi -constrained cementedprosthesis	Same	Same	Same
Principle ofOperation	Cemented Usefixed Bearing Design	Same	Same	Same
Patient-Specific	Yes	Yes	No	No
PatellarDesign/Dimensions	Symmetrical, offered insizes ranging from 32, 35,38 and 41 mm, withcorresponding heights of6, 7, 8.5 and 10 mm	Offset Dome	Symmetrical orAsymmetrical, offered insizes ranging from 27 to39 mm in diameter and 8to 11 mm in thickness.	Symmetrical, offered in sizesranging from 26 to 41mm indiameter and 7 to 9 mm inthickness
MinimumThickness ofTibial Insert(UHMWPE)	6 mm	All poly tibialcomponent -6mm	6mm	6mm
PosteriorCruciateLigament(PCL) Sparing	Yes	Yes	Yes	NoPosterior stabilized

Traditional 510(k) – ConforMIS iTotal CR Knee Replacement System

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K094050-03/5

Traditional 510(k) – ConforMIS iTotal CR Knee Replacement System

・

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Koryato 4/5

Traditional 510(k) – ConforMIS iTotal CR Knee Replacement System

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K094050 * 5/5

Safety and Performance:

The determination of substantial equivalence for this device was based on a detailed device description. Non-clinical laboratory testing was performed demonstrating that the device is safe and can be considered substantially equivalent to the predicate devices for the proposed intended use.

The following testing was performed on the subject device: Femoral Fatigue Testing, Kinematic Range of Motion Testing, Stability Characteristics Testing, Patello-Femoral Lateral Stability Testing, Contact Area and Surface Stress for the Patello-Femoral Articulation testing, Tibial-Femoral Contact Areas and Stress Testing, Modular Assembly and Disassembly Characteristics of the iTotal Tibial Plateau Testing and UHMWPE Characterization. Clinical data is not necessary to demonstrate substantial equivalence. Results of the bench testing conducted demonstrate that the iTotal KRS is substantially equivalent to the Predicate Knee Systems.

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Image /page/5/Picture/0 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized symbol that resembles an abstract caduceus or a bird-like figure with three wing-like shapes.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Room -WO66-G609 Silver Spring, MD 20993-0002

ConforMIS, Inc. % Ms. Amita S. Shah 2 Fourth Avenue Burlington, Massachusetts 01803

SEP 1 3 2010

Re: K094050

Trade/Device Name: ConforMIS iTotal® Cruciate Retaining (CR) Knee Replacement

System

Regulation Number: 21 CFR 888.3560

Regulation Name: Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prothesis

Regulatory Class: II Product Code: JWH Dated: July 16, 2010 Received: July 19, 2010

Dear Ms. Shah:

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. 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 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

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Page 2 - Ms. Amita S. Shah

CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm' for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm1.

Sincerely yours,

Mark A. Milkein

Mark N. Melkerson Director Division of Surgical. Orthopedic and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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INDICATION FOR USE STATEMENT 4.0

510(k) Number (if known): KO9YOSO

Device Name: ConforMIS iTotal® Cruciate Retaining (CR) Knee Replacement System

Indications for Use:

The iTotal® 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 bothe use of a prosthetic device that treats only one or two of the three knee compartments, such as a unicondylar, patello-femoral or bi-compartmental 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, hemiarthoplasties, and unicondylar, patello-femoral or bi-compartmental . implants.

The iTotal CR KRS is intended for cemented use only.

Prescription Use _____________________________________________________________________________________________________________________________________________________________ (Part 21 CFR 801 Subpart D)

AND/OR

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

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Soutu for mxm

and Restorative Devices

510(k) Number Ko 94050

Traditional 510(k) - ConforMIS iTotal CR Knee Replacement System

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.