Moderately disabling joint disease of the knee resulting from painful osteo- or post traumatic arthritis
Revision of previous unsuccessful surgical procedures, either involving, or not involving, previous use of a unicompartmental knee prosthesis
As an alternative to tibial osteotomy in patients with unicompartmental osteoarthritis
Where bone stock is of poor quality or inadequate for other reconstructive techniques as indicated by deficiencies of the femoral condyle/tibial plateau.
These components are intended for implantation with bone cement.

Mako X3® Uni Onlay Tibial Inserts are components of the RESTORIS™ Multicompartmental Knee (MCK) System that is indicated for single or multi-compartmental knee replacement used in conjunction with RIO®, the Robotic Arm Interactive Orthopedic System, in individuals with osteoarthritis or post-traumatic arthritis of the tibiofemoral and/or patellofemoral articular surfaces. The specific knee replacement configurations include:

Medial unicondylar
Lateral unicondylar
Patellofemoral
Medial bi-compartmental (medial unicondylar and patellofemoral)
RESTORIS™ Multicompartmental Knee (MCK) System is for single use only and is intended for implantation with bone cement.

Device Description

The subject Triathlon PKR X3® Tibial Inserts and Mako X3® Uni Onlay Tibial Inserts are identical in design to their currently marketed predicates. The subject inserts will use a different method of terminal sterilization of ethylene oxide per ISO 11135 and will be formed by consolidating GUR1020 resin via conventional methods which meet the specifications of ASTM F648. The device sterilization method is identical to that used for the reference Triathlon X3 Tibial Inserts and Patellar Components.

AI/ML Overview

This FDA 510(k) summary (K180612) describes a premarket notification for new versions of tibial inserts for knee replacement systems. Crucially, the document explicitly states that "Clinical Testing was not required as a basis for substantial equivalence." This means that the device's acceptance criteria and proof of meeting them are not based on clinical performance data (e.g., patient outcomes, diagnostic accuracy of an AI). Instead, the substantial equivalence determination relies on comparisons to legally marketed predicate devices through non-clinical testing.

Therefore, many of the questions you asked, which are relevant to clinical studies (especially those involving AI or human readers), cannot be answered from this document.

Here's an analysis based on the provided text, addressing what can be inferred and explaining why other information is not present:

Device Acceptance Criteria and Performance (Based on Non-Clinical Testing)

Since clinical testing was not required, the acceptance criteria are based on mechanical and material properties, sterilization efficacy, and biocompatibility, demonstrating that the new devices are equivalent to established predicates.

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria Category	Specific Criteria (Implicitly Met by Testing)	Reported Device Performance (Summary from Document)
Material Properties	Conform to ASTM F648 for UHMWPE.	New device uses GUR1020 resin consolidated via conventional methods, meeting ASTM F648 specifications.
Biocompatibility	Meet EN ISO 10993-1:2010 and FDA Guidance.	Biocompatibility testing per EN ISO 10993-1:2010.
Sterilization Efficacy	Meet EN ISO 11135:2014 for Ethylene Oxide (EtO) sterilization.	Ethylene Oxide Sterilization Validation per EN ISO 11135:2014.
Pyrogenicity	Bacterial endotoxin limit <20 EU/Device.	Bacterial endotoxin testing (BET) per ANSI/AAMI ST72:2011 achieved <20 EU/Device.
Mechanical Performance	Equivalent to predicates for: Static Shear Insert Baseplate Locking Mechanism; Posterior Edge Fatigue.	Static Shear Insert Baseplate Locking Mechanism Test and Posterior Edge Fatigue Test performed, demonstrating equivalence to predicates.
MR Safety	Conform to ASTM F2503-05 and related ASTM standards for MR-conditional labeling.	MR safety evaluation per ASTM F2052, F2213, F2119, F2182. Labeled as MR-conditional.
Design & Operational Principles	Identical to predicate devices.	"identical in design," "identical in intended use, indications, design, and operational principles as the predicate devices."

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

Sample Size: Not applicable in the traditional sense of a clinical test set with patient data. The "test set" here refers to physical samples of the device and materials used for the non-clinical laboratory tests. The document does not specify the number of samples used for each test (e.g., how many inserts were subjected to fatigue testing).
Data Provenance: The data provenance is from laboratory testing performed by the manufacturer (Howmedica Osteonics Corp aka Stryker Orthopaedics). The document does not specify the country of origin of the labs, but it's likely internal or contracted labs supporting the US market submission. The nature of the data is pre-market non-clinical laboratory testing.

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

Not applicable. There is no "ground truth" in the diagnostic or clinical sense established by human experts in this type of submission. The "ground truth" for non-clinical tests is established by adherence to recognized international standards (e.g., ASTM, ISO) and the physical measurements themselves.

4. Adjudication Method for the Test Set

Not applicable. Adjudication methods like 2+1 or 3+1 are used for clinical test sets where there's human interpretation involved. For non-clinical lab tests, results are typically objective measurements against a validated standard, not requiring adjudication.

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

No, not applicable. This submission is for knee joint implants, not an AI-assisted diagnostic device. The document explicitly states: "Clinical Testing: Clinical testing was not required as a basis for substantial equivalence."

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

No, not applicable. This is not an algorithmic device.

7. The Type of Ground Truth Used

For non-clinical testing: The "ground truth" for the non-clinical tests is based on established engineering and material science standards (e.g., ASTM, ISO). For example, the ground truth for material properties is the specified values and tolerances in ASTM F648; for sterilization, it's the sterility assurance level defined in ISO 11135.

8. The Sample Size for the Training Set

Not applicable. There is no "training set" as this is not an AI/machine learning device.

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

Not applicable. As above, no training set or AI model.

Conclusion from the Document:

The FDA determined that the Triathlon® PKR X3® Tibial Inserts and Mako X3® Uni Onlay Tibial Inserts are substantially equivalent to their predicate devices (Triathlon PKR System X3 Tibial Inserts - K071881, K172326; Restoris Multicompartmental Knee (MCK) System X3 Tibial Inserts - K150307, K172326). This determination was made based on non-clinical testing that confirmed:

Identical intended use, indications, design, and operational principles to the predicate devices.
Material properties meeting the same standards (ASTM F648) as the predicate.
The only significant change was the terminal sterilization method (from Gas Plasma to Ethylene Oxide), which was validated to meet relevant standards (EN ISO 11135:2014) and found acceptable by comparison to a previously cleared device with the same sterilization change (K172634).
Other non-clinical tests (biocompatibility, mechanical performance, pyrogenicity, MR safety) were performed and found to support equivalence.

No human clinical data, AI performance metrics, or diagnostic accuracy studies were part of this 510(k) submission.

Summary

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Image /page/0/Picture/0 description: The image shows the logos of the Department of Health and Human Services and the Food and Drug Administration (FDA). The Department of Health and Human Services logo is on the left, and the FDA logo is on the right. The FDA logo is a blue square with the letters "FDA" in white, followed by the words "U.S. Food & Drug Administration" in blue.

June 7, 2018

Howmedica Osteonics Corp aka Stryker Orthopaedics Emily DiMambro Regulatory Affairs Specialist 325 Corporate Drive Mahwah, New Jersey 07430

Re: K180612

Trade/Device Name: Triathlon® PKR X3® Tibial Inserts, Mako X3® Uni Onlay Tibial Inserts Regulation Number: 21 CFR 888.3520 Regulation Name: Knee Joint Femorotibial Metal/Polymer Non-Constrained Cemented Prosthesis Regulatory Class: Class II Product Code: HSX, HRY, NPJ Dated: February 28, 2018 Received: March 8, 2018

Dear Emily DiMambro:

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 CFR Part 807); labeling (21 CFR Part 801); medical device reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820);

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1000-1050.

and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR

K180612

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 http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm.

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/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). 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 (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerely.

Katherine D. Kavlock -S

for

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

Enclosure

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DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2020 See PRA Statement below.

510(k) Number (if known) K180612

Device Name:

Mako X3® Uni Onlay Tibial Inserts

Indications for Use (Describe)

Mako X3® Uni Onlay Tibial Inserts are components of the RESTORIS Multicompartmental Knee (MCK) System that is indicated for single or multi-compartment used in conjunction with RIO®, the Robotic Arm Interactive Orthopedic System, in individuals with osteoarthritis of the tibiofemoral and/or patellofemoral articular surfaces. The specific knee replacement configurations include:

Medial unicondylar
Lateral unicondylar
· Patellofemoral

· Medial bi-compartmental (medial unicondylar and patellofemoral)

RESTORIS Multicompartmental Knee (MCK) System is for single use only and is intended for implantation with bone cement.

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 NECESSARY

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 time to review instructions, search existing data sources, gather and maintain the data needed and complete and review the collection of information. 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."

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DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration

Indications for Use

Form Approved: OMB No. 0910-0120 Expiration Date: 06/30/2020 See PRA Statement below.

510(k) Number (if known)

K180612

Device Name:

Triathlon® PKR X3® Tibial Inserts

Indications for Use (Describe)

Triathlon® PKR X3® Tibial Inserts are components of the Triathlon® PKR System that is indicated for:

· Moderately disabling joint disease of the knee resulting from painful osteo- or post traumatic arthritis
· Revision of previous unsuccessful surgical procedures, either involving, or not involving, previous use of a unicompartmental knee prosthesis
· As an alternative to tibial osteotomy in patients with unicompartmental osteoarthritis

· Where bone stock is of poor quality or inadequate for other reconstructive techniques as indicated by deficiencies of the femoral condyle/tibial plateau.

These components are intended for implantation with bone cement.

	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)

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.

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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510(k) Summary

Sponsor	Howmedica Osteonics Corp aka Stryker Orthopaedics325 Corporate Drive Mahwah, NJ 07430
Contact Person	Emily DiMambroRegulatory Affairs SpecialistHowmedica Osteonics Corp325 Corporate DriveMahwah, NJ 07430Phone: (201) 831-5140; Fax: (201) 831-4559
Alternate Contact	Karen AriemmaSr. Manager, Regulatory AffairsHowmedica Osteonics Corp325 Corporate DriveMahwah, NJ 07430Phone: (201) 831-5718 ; Fax: (201)-831-4559
Date Prepared:	February 28, 2018
Proprietary Name:	Triathlon® PKR X3® Tibial Inserts and Mako X3® Uni Onlay TibiaInserts
Common Name:	Partial Knee Joint Replacement
Classification Name:	21 CFR 888.3520 - Knee joint femorotibial metal/polymer non constrained cemented prosthesis
Product Codes:	HSX, HRY, NPJ

Legally Marketed Devices to Which Substantial Equivalence is Claimed:

Triathlon PKR System X3 Tibial Inserts (K071881, K172326) .
Restoris Multicompartmental Knee (MCK) System X3 Tibial Inserts (K150307, ● K172326)

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Legally Marketed Reference Devices Used to Support Substantial Equivalence:

. Triathlon X3 Tibial Inserts and Patellar Components (K172634)
Device Description: The subject Triathlon PKR X3® Tibial Inserts and Mako X3® Uni Onlay Tibial Inserts are identical in design to their currently marketed predicates. The subject inserts will use a different method of terminal sterilization of ethylene oxide per ISO 11135 and will be formed by consolidating GUR1020 resin via conventional methods which meet the specifications of ASTM F648. The device sterilization method is identical to that used for the reference Triathlon X3 Tibial Inserts and Patellar Components.

Intended Use:

The subject devices have the same intended use as those specified in the 510(k) clearances for the predicate devices listed.

Indications:

Device Name: Triathlon® PKR X3® Tibial Inserts

Indications for Use:

Triathlon® PKR X3® Tibial Inserts are components of the Triathlon® PKR System that is indicated for:

Moderately disabling joint disease of the knee resulting from painful osteo- or post traumatic arthritis
Revision of previous unsuccessful surgical procedures, either involving, or not involving, . previous use of a unicompartmental knee prosthesis
. As an alternative to tibial osteotomy in patients with unicompartmental osteoarthritis
Where bone stock is of poor quality or inadequate for other reconstructive techniques as ● indicated by deficiencies of the femoral condyle/tibial plateau.

These components are intended for implantation with bone cement.

Device Name: Mako X3® Uni Onlay Tibial Inserts

Indications for Use:

Medial unicondylar
Lateral unicondylar
· Patellofemoral
Medial bi-compartmental (medial unicondylar and patellofemoral)

RESTORIS™ Multicompartmental Knee (MCK) System is for single use only and is intended for implantation with bone cement.

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Summary of Technological Characteristics: The subject components are identical in intended use, indications, design, and operational principles as the predicate devices. The subject devices are different from the predicate devices in their terminal sterilization method. The subject devices are terminally sterilized by Ethylene Oxide, whereas the predicate devices are sterilized using Gas Plasma. Consolidation of the X3® polyethylene material will be performed via conventional methods. The X3® UHMWPE continues to meet the same ASTM F648 specification. Both the subject and predicate Triathlon PKR X3® Tibial Inserts and Mako X3® Uni Onlay Tibial Inserts are labeled as MR-conditional according to the terminology specified in ASTM F2503-05. MR-conditional labeling for the predicate devices was cleared in K172326.

An identical change in sterilization for the Triathlon X3® Total Knee Tibial Insert and Patellar Components was cleared in K172634.

Non-Clinical Testing: The following non-clinical laboratory testing was performed to determine substantial equivalence:

1. Material Testing per ASTM F648, ASTM F2565, and FDA Guidance, "Characterization of Ultrahigh Molecular Weight Polyethylene (UHMWPE) Used in Orthopedic Devices" (February 12, 2016).
1. Biocompatibility Testing per EN ISO 10993-1:2010 and FDA Guidance, "Use of International Standard ISO 10993-1, "Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process" (June 16, 2016)
1. Ethylene Oxide Sterilization Validation per EN ISO 11135:2014
1. Static Shear Insert Baseplate Locking Mechanism Test
1. Posterior Edge Fatigue Test
1. Bacterial endotoxin testing (BET) as specified in ANSI/AAMI ST72:2011 was used for pyrogenicity testing to achieve an Endotoxin limit of <20 EU/Device
1. MR safety evaluation per ASTM F2052-2015, ASTM F2213-2011, ASTM F2119-2007, and ASTM F2182-2011

Clinical Testing: Clinical testing was not required as a basis for substantial equivalence.

Conclusion: The subject Triathlon PKR X3® Tibial Inserts and Mako X3® Uni Onlay Tibial Inserts are substantially equivalent to the predicate devices identified in this premarket notification.

Device comparison showed that the proposed devices are substantially equivalent in intended use, materials, and performance characteristics to their respective predicate devices. The proposed modification does not affect safety or effectiveness.

Regulation Number and Section

§ 888.3520 Knee joint femorotibial metal/polymer non-constrained cemented prosthesis.

(a)
Identification. A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device limits minimally (less than normal anatomic constraints) translation in one or more planes. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral condylar resurfacing component or components made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components made of ultra-high molecular weight polyethylene and are intended for use with bone cement (§ 888.3027).(b)
Classification. Class II.