The VariAx 2 Distal Radius System is indicated for the fixation of fractures, nonunions, and malunions of the bones of the hand and wrist, including osteopenic bone.
The VariAx 2 Distal Ulna System is indicated for the fixation of fractures, nonunions, and malunions of the wrist, including osteopenic bone.

Device Description

The distal radius plates consist of an anatomically shaped Dorsal DR Plate for the double column DR fractures. The anatomically shaped Dorsal Lateral DR, Dorsal Medial DR, Lateral DR and Volar Rim DR plates are used for fragment specific plating of the distal radius. Lateral DR plate for the radial styloid fractures, a Dorsal Medial DR Plate and a Dorsal Lateral DR Plate for the medially or laterally displaced dorsal DR fractures, and a Volar Rim DR Plate for the volar rim DR fractures. The Lateral DR plate, Dorsal Medial DR and Dorsal Lateral DR plates will provide screw/peg fixation of the distal DR fragments as an optional to fixation with K-wires. The Wrist Spanning plate is intended for temporary internal fixation of the comminuted distal radius fractures and wrist and serves as an alternative to an External Fixator. Additionally, it can be applied for complementary stabilization in combination with the other fracture fixation plates.
The VariAx 2 Distal Ulna (DU) plates consist of the DU Base Plate and the DU Hook Plate. The DU hook plate is used for fixation of ulnar styloid fractures and the DU base plate is used for fractures of the distal ulnar head and/or shaft.
All new VariAx 2 implants will use the well-established SmartLock technology to allow variable angle screw locking. The plates will be available non-sterile in VariAx 2 Wrist Tray, and also sterile-packaged. The plates can be used with non-locking and locking VariAx 2 T8 screws. The VariAx 2 T8 screws have received 510(k) clearance (K180500).
All plates (except the Wrist Spanning plate) are made from CP Ti Grade 2 (anodized Type II). The Wrist Spanning plate is made from Ti Alloy (Ti6Al4V ELI).

AI/ML Overview

This document describes the regulatory clearance (K212581) for the VariAx 2 Distal Radius System and VariAx 2 Distal Ulna System, which are single/multiple component metallic bone fixation appliances and accessories.

Crucially, this document is a 510(k) summary for a medical device that is not an AI-powered diagnostic or therapeutic device. It's a traditional mechanical orthopedic implant. Therefore, the questions related to AI-specific acceptance criteria, ground truth, expert adjudication, MRMC studies, and training/test set sample sizes for AI algorithms are not applicable to this device.

The study described in this document focuses on non-clinical performance data to demonstrate substantial equivalence to predicate devices, rather than clinical performance or AI algorithm validation.

Here's a breakdown based on the provided text, addressing the relevant points and explaining why others are not applicable:

1. Table of Acceptance Criteria and Reported Device Performance

For this type of device (metallic bone fixation), acceptance criteria are typically defined by engineering and mechanical performance standards, ensuring the device is robust enough for its intended use and performs at least as well as legally marketed predicate devices.

Acceptance Criteria Category	Specific Test/Standard	Reported Device Performance (Conclusion)
Mechanical Performance	Dynamic component/construct test (4-point bending according to ASTM F382 and DQI 30-021)	Demonstrated substantial equivalence to predicate systems.
	Dynamic cantilever bending	Demonstrated substantial equivalence to predicate systems.
	Static cantilever bending	Demonstrated substantial equivalence to predicate systems.
	Torque to failure	Demonstrated substantial equivalence to predicate systems.
	Push out force	Demonstrated substantial equivalence to predicate systems.
MR Compatibility	Magnetically-induced displacement force (ASTM F2052)	MR conditional
	Magnetically-induced torque (ASTM F2213)	MR conditional
	RF-induced heating (ASTM F2182)	MR conditional
	Image artifacts (ASTM F2119)	MR conditional
Packaging	ISO 11607-1	Tests performed (implied compliance)
	ISO 11607-2	Tests performed (implied compliance)
Sterilization	Radiation (for sterile-packaged plates)	Method stated (implied validation)

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

Sample Size for Test Set: Not specified in terms of clinical cases or patient data, as the validation was primarily non-clinical (mechanical testing of physical devices). The "test set" here refers to the number of physical devices/components subjected to mechanical and MR compatibility testing. The exact number of units tested per mechanical test is not provided in this summary but would be detailed in the full test reports.
Data Provenance: The data comes from bench testing conducted by the manufacturer, Stryker GmbH. It is inherently "prospective" in the sense that the tests were designed and executed to evaluate the new device's performance against predefined standards. There is no indication of country of origin for "data" as it relates to patient information, as no clinical data was used for substantial equivalence.

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

Not applicable. Ground truth for mechanical performance is established by engineering principles and standardized test methods (e.g., ASTM standards), not by human expert consensus or interpretation of images.

4. Adjudication method for the test set

Not applicable. As described above, there's no expert interpretation or consensus needed for the mechanical and physical property tests performed.

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 device is a mechanical implant, not an AI-powered diagnostic or assistive tool. Therefore, MRMC studies are irrelevant.

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

Not applicable. This is not an algorithm or software device.

7. The type of ground truth used

The "ground truth" for this device's performance is objective, quantifiable mechanical and physical properties as defined by international standards (e.g., ASTM, ISO). It's based on:

Engineering measurements
Material science properties
Adherence to established performance benchmarks (demonstrating equivalence to predicate devices and resistance to various forces/conditions).

8. The sample size for the training set

Not applicable. There is no AI model involved, so there's no training set for an algorithm.

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

Not applicable. There is no AI model involved, so no ground truth for a training set was established.

Summary of Device and its Validation Approach:

The VariAx 2 Distal Radius and VariAx 2 Distal Ulna Systems are orthopedic implants. Their regulatory clearance (K212581) was based on demonstrating substantial equivalence to existing predicate devices already on the market. This was achieved primarily through non-clinical performance testing, specifically mechanical and material property tests (e.g., bending, torque, push-out force, and MR compatibility). The testing showed that the new devices perform at least as safely and effectively as their predicate counterparts, and do not raise new questions of safety or effectiveness. Clinical data was explicitly stated as "not needed" for this demonstration of substantial equivalence.

Summary

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January 19, 2022

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 blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

Stryker GmbH Keith Neligan Senior Staff Regulatory Affairs Specialist Contact Address325 Corporate Drive Mahwah, New Jersey 07430

Re: K212581

Trade/Device Name: VariAx 2 Distal Radius System, VariAx 2 Distal Ulna System Regulation Number: 21 CFR 888.3030 Regulation Name: Single/Multiple Component Metallic Bone Fixation Appliances And Accessories Regulatory Class: Class II Product Code: HRS Dated: August 11, 2021 Received: August 16, 2021

Dear Keith Neligan:

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,

Shumaya Ali, MPH Assistant Director DHT6C: Division of Restorative, Repair and Trauma 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) K212581

Device Name VariAx 2 Distal Radius

Indications for Use (Describe)

The VariAx 2 Distal Radius System is indicated for the fixation of fractures, nonunions, and malunions of the bones of the hand and wrist, including osteopenic bone.

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.

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Indications for Use

510(k) Number (if known) K212581

Device Name VariAx 2 Distal Ulna

Indications for Use (Describe)

The VariAx 2 Distal Una System is indicated for the fixation of fractures, nonunions, and malunions of the wrist, including osteopenic bone.

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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K212581 - 510(k) Summary

Proprietary Name:	VariAx 2 Distal Radius & VariAx 2 Distal Ulna
Common Name:	Plate, Fixation, Bone
Regulation Description:	Single/multiple component metallic bone fixation appliances and accessories.
Regulation Number:	21 CFR 888.3030
Classification Product Code:	HRS
Device Class:	II
Sponsor:	Stryker GMBHBohnackerweg 12545 Selzach, Switzerland
Contact Person:	Keith NeliganSenior Staff Regulatory Affairs SpecialistIDA Business & Technology Park, Carrigtwohill,Co. Cork, Ireland T45 HX08Phone: +00 353 87 7995645Fax: +
Date:	JAN 19, 2022
Predicate Device:	Primary Predicate: VariAx Distal Radius Plating System Line Extension(K133974)
	Additional Predicate Devices: VariAx 2 Mini Fragment & VariAx 2 System(K191412), TriMed Wrist Fixation System (K060041), LCP Distal UlnaPlate (K063049)
Device Description:	The distal radius plates consist of an anatomically shaped Dorsal DR Platefor the double column DR fractures. The anatomically shaped Dorsal LateralDR, Dorsal Medial DR, Lateral DR and Volar Rim DR plates are used forfragment specific plating of the distal radius. Lateral DR plate for the radialstyloid fractures, a Dorsal Medial DR Plate and a Dorsal Lateral DR Plate forthe medially or laterally displaced dorsal DR fractures, and a Volar Rim DRPlate for the volar rim DR fractures. The Lateral DR plate, Dorsal Medial DRand Dorsal Lateral DR plates will provide screw/peg fixation of the distal DRfragments as an optional to fixation with K-wires. The Wrist Spanning plateis intended for temporary internal fixation of the comminuted distal radiusfractures and wrist and serves as an alternative to an External Fixator.Additionally, it can be applied for complementary stabilization incombination with the other fracture fixation plates.The VariAx 2 Distal Ulna (DU) plates consist of the DU Base Plate and theDU Hook Plate. The DU hook plate is used for fixation of ulnar styloidfractures and the DU base plate is used for fractures of the distal ulnar headand/or shaft.K212581 - Page 1
	All new VariAx 2 implants will use the well-established SmartLocktechnology to allow variable angle screw locking. The plates will be availablenon-sterile in VariAx 2 Wrist Tray, and also sterile-packaged. The plates canbe used with non-locking and locking VariAx 2 T8 screws. The VariAx 2 T8screws have received 510(k) clearance (K180500).
	All plates (except the Wrist Spanning plate) are made from CP Ti Grade 2(anodized Type II). The Wrist Spanning plate is made from Ti Alloy(Ti6Al4V ELI).
Indications for Use:	The VariAx 2 Distal Radius System is indicated for the fixation of fractures,osteotomies, nonunions and malunions of the bones of the hand and wrist,including osteopenic bone.
	The VariAx 2 Distal Ulna System is indicated for the fixation of fractures,osteotomies, nonunions and malunions of the wrist, including osteopenicbone.
Comparison to PredicateDevice:	The intended use of the subject devices are similar to those detailed in thepredicate devices. There is no change in the fundamental scientifictechnology shared by both the subject devices and predicate devices.
Performance Data (Nonclinical):	Non-Clinical Performance and Conclusions:The VariAx 2 Distal Radius and VariAx 2 Distal Ulna plates are single usedevices, available in sterile and non-sterile forms. Sterile plate are sterilizedby means of radiation.
	Comparative assessment and mechanical testing to the predicate systemsdemonstrated substantial equivalence. The following factors wereconsidered:● Dynamic component/construct test (4-point bending according toASTM F382 and DQI 30-021)● Dynamic cantilever bending● Static cantilever bending● Torque to failure● Push out force
	The aforementioned testing demonstrated that the VariAx 2 Distal Radiusand VariAx 2 Distal Ulna systems are substantially equivalent to thepredicate devices. Additionally, MR assessments of magnetically-induceddisplacement force per ASTM F2052, magnetically-induced torque perASTM F2213, RF-induced heating per ASTM F2182, and image artifacts perASTM F2119 demonstrate that the VariAx 2 Distal Radius and VariAx 2Distal Ulna systems are MR conditional.
	Packaging tests were performed according ISO 11607-1 and ISO 11607-2.All bench tests performed in accordance with ASTM standards.
	Clinical Performance and Conclusions:Clinical data and conclusions were not needed for these devices todemonstrate substantial equivalence to the predicate devices.
Conclusion:	The subject devices have similar intended use and similar indications for useas the predicate devices. The subject devices use the same operating

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K212581 - Page 2

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principle, incorporate the same basic design and labeling and are manufactured and sterilized using the same materials and processes as the predicate devices.

The performance data and analyses demonstrate that:

· any differences do not raise new questions of safety and effectiveness as established with performance testing; and

• the subject devices are at least as safe and effective as the legally marketed predicate devices

Regulation Number and Section

§ 888.3030 Single/multiple component metallic bone fixation appliances and accessories.

(a)
Identification. Single/multiple component metallic bone fixation appliances and accessories are devices intended to be implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a plate, a nail/plate combination, or a blade/plate combination that are made of alloys, such as cobalt-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners, such as screws and nails, or bolts, nuts, and washers. These devices are used for fixation of fractures of the proximal or distal end of long bones, such as intracapsular, intertrochanteric, intercervical, supracondylar, or condylar fractures of the femur; for fusion of a joint; or for surgical procedures that involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force (traction) may be applied to the skeletal system.(b)
Classification. Class II.