Painful, disabling joint disease of the knee resulting from: noninflammatory degenerative . joint disease (including osteoarthritis, traumatic arthritis, or avascular necrosis), rheumatoid arthritis or post-traumatic arthritis.
Post-traumatic loss of knee joint configuration and function.
. Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.
Revision of previous unsuccessful knee replacement or other procedure. ●
Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture -management techniques.

The Triathlon® Tritanium® Total Knee System components are indicated for both uncemented and cemented use.

The Triathlon® Total Knee System beaded and beaded with Peri-Apatite components are intended for uncemented use only.

The Triathlon® All Polyethylene tibial components are indicated for cemented use only.

Additional Indications for Posterior Stabilized (PS) and Total Stabilizer (TS) Components:

. Ligamentous instability requiring implant bearing surface geometries with increased constraint.
Absent or non-functioning posterior cruciate ligament.
Severe anteroposterior instability of the knee joint. ●

Additional Indications for Total Stabilizer (TS) Components:

Severe instability of the knee secondary to compromised collateral ligament integrity or ● function.
Indications for Bone Augments:
Painful, disabling joint disease of the knee secondary to: degenerative arthritis, . rheumatoid arthritis, or post-traumatic arthritis, complicated by the presence of bone loss.
Salvage of previous unsuccessful total knee replacement or other surgical procedure, . accompanied by bone loss.

Additional Indications for Cone Augments:

Severe degeneration or trauma requiring extensive resection and replacement .
Femoral and Tibial bone voids ●
Metaphyseal reconstruction o

The Triathlon TS Cone Augment components are intended for cemented or cementless use.

Indications for Use for the Triathlon Tritanium Tibial Baseplate are:
General Total Knee Arthroplasty (TKR) Indications:

. Painful, disabling joint disease of the knee resulting from: non-inflammatory degenerative joint disease (including osteoarthritis, traumatic arthritis or avascular necrosis) or rheumatoid arthritis
Post-traumatic loss of knee joint configuration and function ●
Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be ● returned to adequate function and stability
Revision of previous unsuccessful knee replacement or other procedure
Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture management techniques

Additional General Total Knee Arthroplasty (TKR) Indications specific to the PS implant:

Ligamentous instability requiring implant bearing surface geometries with increased o constraint
. Absent or non-functioning posterior cruciate ligament
Severe anteroposterior instability of the knee joint .

The Triathlon Tritanium Tibial Baseplates are indicated for both cemented and uncemented use.

Indications for Use for the Triathlon Low Profile Tibial Tray are:
The Triathlon Low Profile Tibial Tray is intended to be used with commercially available Triathlon® femoral components and associated patellar components, and tibial bearing inserts in primary cemented total knee arthroplasty. The indications for the Triathlon® Low Profile Tibial Tray are outlined below:

Indications for Use:

· Painful, disabling joint disease of the knee resulting from: degenerative arthritis, rheumatoid arthritis or post-traumatic arthritis.
· Post-traumatic loss of knee joint configuration and function.
· Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.

Indications for Use for the Triathlon Metal Backed Patella are:

. Noninflammatory degenerative joint disease including osteoarthritis, traumatic arthritis or avascular necrosis;
Rheumatoid arthritis; .
Correction of functional deformity; ●
Revision procedures where other treatments or devices have failed; ●
Post traumatic loss of joint anatomy, particularly when there is patello-femoral erosion, ● dysfunction or prior patellectomy; and,
Irreparable fracture of the knee. .

These products are intended to achieve fixation without the use of bone cement.

Indications for Use for the Triathlon PKR System are:

. 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.

Indications for Use for the Restoris MCK System:
Restoris MCK is indicated for single or multi-compartmental knee replacement used in conjunction with RIQ, 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 Multi Compartmental Knee is for single use only and is intended for implantation with bone cement.

Device Description

The devices covered by this submission include femoral components, tibial baseplates, tibial inserts, all-polyethylene tibial components, patellar components, metal backed patellar components, tibial and femoral augments, stems, stem extenders and offset adaptors used in total knee arthroplasty procedures, as well as femoral components, tibial inserts, tibial baseplates, patellofemoral components and patellar components used in partial knee replacements. All devices have been previously determined substantially equivalent in prior 510(k) submissions and are commercially available. The Triathlon/Restoris Knee system components are manufactured from the following materials Cobalt Chromium Alloy, Titanium Alloy, Commercially Pure Titanium, Ultra-High Molecular Weight Polyethylene and Calcium Phosphate.

The purpose of this submission is to modify the labeling of the Triathlon Total Knee System, Triathlon PKR System, and Restoris MCK System to add MR Conditional labeling. Additionally, a revision to the contraindications for the Triathlon PKR System is being made.

AI/ML Overview

This document describes the premarket notification (510(k)) for the Stryker Orthopaedics Triathlon Total Knee System, Triathlon PKR System, and Restoris MCK System. The submission primarily focuses on modifying the labeling to add MR Conditional labeling and revising contraindications for the Triathlon PKR System. Therefore, the "device" in question is the existing knee replacement systems with updated MRI compatibility information.

As such, the provided text DOES NOT describe a study that proves a device meets acceptance criteria related to its functional performance (e.g., accuracy, sensitivity, specificity, or improvement in human reader performance for an AI/CAD device). Instead, it details the non-clinical testing performed to establish the MR compatibility of the knee systems.

Given this, I will tailor the answer to reflect the information available regarding the MR compatibility studies, rather than a clinical performance study often associated with AI/CAD devices.

Here's a breakdown of the acceptance criteria and the study that proves the device meets them, based on the provided text:

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

The acceptance criteria are implicitly defined by the standards and guidance used for MR compatibility testing. The reported performance is that the devices passed these tests and are therefore deemed "MR Conditional" under specific parameters.

Acceptance Criteria Category	Specific Criteria (Implicit from Standards)	Reported Device Performance
Magnetically Induced Displacement Force	Device should not experience significant displacement force in a specified MR environment (per ASTM F2052-15)	Tests performed, results indicate compliance for MR Conditional labeling.
Magnetically Induced Torque	Device should not experience significant torque in a specified MR environment (per ASTM F2213-06 (Reapproved 2011))	Tests performed, results indicate compliance for MR Conditional labeling.
Image Artifact	Device should not cause unacceptable image artifacts in MR images (per ASTM F2119-07 (Reapproved 2013))	Tests performed, results indicate compliance for MR Conditional labeling.
Heating by RF Fields	Device should not heat excessively during MR imaging (per ASTM F2182-11a and FDA guidance "Assessment of Radiofrequency-Induced Heating...")	Tests performed, results indicate compliance for MR Conditional labeling.
Labeling Compliance	Device labeling must reflect safe MR scanning parameters.	Labeling modified to include MR conditional symbol and parameters.
Contraindication Review	Contraindications are appropriate and updated as needed.	For certain devices, a contraindication was removed based on this update.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The text does not specify the sample size in terms of the number of devices tested for MR compatibility. Typically, for such non-clinical bench testing, a representative sample of device types and sizes would be tested according to the standards. The data provenance is "non-clinical laboratory testing." This is implicitly a prospective study conducted in a controlled lab setting, not involving human or animal data, and thus no country of origin for patients or retrospective/prospective human data is applicable.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This question is not applicable to the type of testing performed. For MR compatibility, the "ground truth" is established by the physical measurements taken according to standardized test methods (e.g., measuring temperature rise, displacement, torque, or evaluating artifact characteristics against defined limits). This does not involve human expert consensus on diagnostic images.

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

This question is not applicable to the type of testing performed. Adjudication methods are typically used when human interpretation of data (e.g., radiologist reads) is required to establish ground truth or evaluate performance, for example in clinical trials of AI algorithms. For MR compatibility testing, the results are objectively measured per established standards.

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 such study was performed or described. This type of study is relevant for AI/CAD devices where human reader performance is a key metric. This submission is for knee implants and their MR compatibility, not an AI device.

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

This question is not applicable. The device is a physical knee implant, not an algorithm.

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

The ground truth for MR compatibility testing is based on:

Physical measurements: Quantifiable measurements of magnetic force, torque, temperature rise, and the extent of image artifacts, as defined by the respective ASTM standards.
Standardized protocols: Adherence to established test methods that determine safety in the MR environment.

This is a form of objective, physical measurement ground truth, not based on expert consensus, pathology, or outcomes data.

8. The sample size for the training set

This question is not applicable. The device is a physical product (knee implant) and there is no mention of an AI/machine learning component that would require a training set.

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

This question is not applicable as there is no training set mentioned for this product.

Summary

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Image /page/0/Picture/0 description: The image contains the logos of the U.S. Department of Health & Human Services and the U.S. Food & Drug Administration (FDA). The Department of Health & Human Services logo is on the left, featuring a stylized eagle. To the right of that is the FDA logo, which includes the letters "FDA" in a blue square, followed by the words "U.S. FOOD & DRUG" in blue, with "ADMINISTRATION" underneath.

October 30, 2017

Stryker Orthopaedics Margaret Klippel Senior Regulatory Affairs Project Manager 325 Corporate Drive Mahwah, New Jersey 07430

Re: K172326

Trade/Device Name: Triathlon Total Knee System. Triathlon PKR System. Restoris MCK Knee System Regulation Number: 21 CFR 888.3560 Regulation Name: Knee joint patellofemorotibial polymer semi-constrained cemented prosthesis Regulatory Class: Class II Product Code: JWH, MBH, HRY, KRR, HSX, NPJ Dated: July 31, 2017 Received: August 1, 2017

Dear Ms. Klippel:

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 (QS) regulation (21 CFR Part 820);

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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 contact the Division of Industry and Consumer Education (DICE) at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm. 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 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 Industry and Consumer Education (DICE) at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely.

Mark N. Melkerson -S

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

Enclosure

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510(k) Number (if known):

Device Name: Triathlon Knee System

Indications for Use:

General Total Knee Arthroplasty (TKR) Indications:

Painful, disabling joint disease of the knee resulting from: noninflammatory degenerative . joint disease (including osteoarthritis, traumatic arthritis, or avascular necrosis), rheumatoid arthritis or post-traumatic arthritis.
Post-traumatic loss of knee joint configuration and function.
. Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.
Revision of previous unsuccessful knee replacement or other procedure. ●
Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture -management techniques.

The Triathlon® Tritanium® Total Knee System components are indicated for both uncemented and cemented use.

The Triathlon® Total Knee System beaded and beaded with Peri-Apatite components are intended for uncemented use only.

The Triathlon® All Polyethylene tibial components are indicated for cemented use only.

Additional Indications for Posterior Stabilized (PS) and Total Stabilizer (TS) Components:

. Ligamentous instability requiring implant bearing surface geometries with increased constraint.
Absent or non-functioning posterior cruciate ligament.
Severe anteroposterior instability of the knee joint. ●

Additional Indications for Total Stabilizer (TS) Components:

Severe instability of the knee secondary to compromised collateral ligament integrity or ● function.
Indications for Bone Augments:
Painful, disabling joint disease of the knee secondary to: degenerative arthritis, . rheumatoid arthritis, or post-traumatic arthritis, complicated by the presence of bone loss.
Salvage of previous unsuccessful total knee replacement or other surgical procedure, . accompanied by bone loss.

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Additional Indications for Cone Augments:

Severe degeneration or trauma requiring extensive resection and replacement .
Femoral and Tibial bone voids ●
Metaphyseal reconstruction o

The Triathlon TS Cone Augment components are intended for cemented or cementless use.

Prescription Use Over-The-Counter Use X AND/OR (Part 21 CFR 801 Subpart D) (21 CFR 807 Subpart C) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

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510(k) Number (if known):

Device Name: Triathlon Tritanium Tibial Baseplate

Indications for Use:

General Total Knee Arthroplasty (TKR) Indications:

. Painful, disabling joint disease of the knee resulting from: non-inflammatory degenerative joint disease (including osteoarthritis, traumatic arthritis or avascular necrosis) or rheumatoid arthritis
Post-traumatic loss of knee joint configuration and function ●
Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be ● returned to adequate function and stability
Revision of previous unsuccessful knee replacement or other procedure
Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture management techniques

Additional General Total Knee Arthroplasty (TKR) Indications specific to the PS implant:

Ligamentous instability requiring implant bearing surface geometries with increased o constraint
. Absent or non-functioning posterior cruciate ligament
Severe anteroposterior instability of the knee joint .

The Triathlon Tritanium Tibial Baseplates are indicated for both cemented and uncemented use.

Over-The-Counter Use Prescription Use X AND/OR (21 CFR 807 Subpart C) (Part 21 CFR 801 Subpart D) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

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510(k) Number (if known):

Device Name: Triathlon Low Profile Tibial Tray

Indications for Use:

The Triathlon Low Profile Tibial Tray is intended to be used with commercially available Triathlon® femoral components and associated patellar components, and tibial bearing inserts in primary cemented total knee arthroplasty. The indications for the Triathlon® Low Profile Tibial Tray are outlined below:

Indications for Use:

· Painful, disabling joint disease of the knee resulting from: degenerative arthritis, rheumatoid arthritis or post-traumatic arthritis.
· Post-traumatic loss of knee joint configuration and function.
· Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.

Prescription Use X Over-The-Counter Use AND/OR (Part 21 CFR 801 Subpart D) (21 CFR 807 Subpart C) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

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510(k) Number (if known):

Device Name: Triathlon Metal Backed Patella

Indications for Use:

Noninflammatory degenerative joint disease including osteoarthritis, traumatic arthritis or o avascular necrosis;
Rheumatoid arthritis; .
Correction of functional deformity; ●
Revision procedures where other treatments or devices have failed; ●
Post traumatic loss of joint anatomy, particularly when there is patello-femoral erosion, ● dysfunction or prior patellectomy; and,
Irreparable fracture of the knee.

These products are intended to achieve fixation without the use of bone cement.

Over-The-Counter Use Prescription Use X AND/OR (21 CFR 807 Subpart C) (Part 21 CFR 801 Subpart D) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

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510(k) Number (if known):

Device Name: Triathlon PKR System

Indications for Use:

. 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.

Over-The-Counter Use Prescription Use X AND/OR (21 CFR 807 Subpart C) (Part 21 CFR 801 Subpart D) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

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510(k) Number (if known):

Device Name: Restoris MCK

Restoris MCK is indicated for single or multi-compartmental knee replacement used in conjunction with RIQ, 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 Multi Compartmental Knee is for single use only and is intended for implantation with bone cement.

Prescription Use X (Part 21 CFR 801 Subpart D) AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)

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

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510(k) Summary

Sponsor	Stryker Orthopaedics325 Corporate DriveMahwah, NJ 07430
Contact Person	Margaret KlippelSenior Principal Regulatory Affairs Project ManagerStryker Orthopaedics325 Corporate DriveMahwah, NJ 07430Telephone: 201-831-5559Fax: 201-831-4559
Date Prepared:	October 26, 2017
Proprietary Name:	Triathlon Total Knee SystemTriathlon Partial Knee SystemRestoris MCK System
Common Name:	Total/Partial Knee Joint Replacement
Classification Name:	Knee joint patellofemorotibial metal/polymer porous-coateduncemented prosthesis. (888.3565)
	Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis (888.3560)
	Knee joint femorotibial metal/polymer semi- constrained cementedprosthesis (888.3530)
	Knee joint patellofemoral polymer/metal semi-constrained cementedprosthesis (888.3540)
	Knee joint femorotibial metal/polymer non-constrained cementedprosthesis (888.3520)
Product Codes:	JWH, MBH, HRY, KRR, HSX, NPJ

Legally Marketed Device to Which Substantial Equivalence is Claimed: Triathlon Total Knee System components cleared via the following 510(k) submissions: K031729, K040267, K042883, K042993, K050539, K051146, K051380, K053514, K061521, K062037, K063423, K070095, K072221, K072575, K123166, K123486, K132624, K141056 and K143393; Triathlon PKR System cleared via K071881; Restoris MCK System cleared via K090763 and K150307.

Device Description:

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Indications:

There are no changes to the previously cleared indications for use.

General Total Knee Arthroplasty (TKR) Indications:

Painful, disabling joint disease of the knee resulting from: noninflammatory degenerative o joint disease (including osteoarthritis, traumatic arthritis, or avascular necrosis), rheumatoid arthritis or post-traumatic arthritis.
Post-traumatic loss of knee joint configuration and function.
Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.
Revision of previous unsuccessful knee replacement or other procedure. ●
o Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture -management techniques.

The Triathlon® Tritanium® Total Knee System components are indicated for both uncemented and cemented use.

The Triathlon® Total Knee System beaded and beaded with Peri-Apatite components are intended for uncemented use only.

The Triathlon® All Polyethylene tibial components are indicated for cemented use only.

Additional Indications for Posterior Stabilized (PS) and Total Stabilizer (TS) Components:

Ligamentous instability requiring implant bearing surface geometries with increased ● constraint.
Absent or non-functioning posterior cruciate ligament.
Severe anteroposterior instability of the knee joint. ●

Additional Indications for Total Stabilizer (TS) Components:

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0 Severe instability of the knee secondary to compromised collateral ligament integrity or function.
Indications for Bone Augments:
Painful, disabling joint disease of the knee secondary to: degenerative arthritis, . rheumatoid arthritis, or post-traumatic arthritis, complicated by the presence of bone loss.
o Salvage of previous unsuccessful total knee replacement or other surgical procedure, accompanied by bone loss.

Additional Indications for Cone Augments:

Severe degeneration or trauma requiring extensive resection and replacement 0
Femoral and Tibial bone voids ●
. Metaphyseal reconstruction

The Triathlon TS Cone Augment components are intended for cemented or cementless use.

Indications for Use for the Triathlon Tritanium Tibial Baseplate are:

General Total Knee Arthroplasty (TKR) Indications:

Painful, disabling joint disease of the knee resulting from: non-inflammatory . degenerative joint disease (including osteoarthritis, traumatic arthritis or avascular necrosis) or rheumatoid arthritis
Post-traumatic loss of knee joint configuration and function .
Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability
Revision of previous unsuccessful knee replacement or other procedure
. Fracture of the distal femur and/or proximal tibia that cannot be stabilized by standard fracture management techniques

Additional General Total Knee Arthroplasty (TKR) Indications specific to the PS implant:

Ligamentous instability requiring implant bearing surface geometries with increased constraint
Absent or non-functioning posterior cruciate ligament ●
Severe anteroposterior instability of the knee joint ●

The Triathlon Tritanium Tibial Baseplates are indicated for both cemented and uncemented use.

Indications for Use for the Triathlon Low Profile Tibial Tray are:

The Triathlon Low Profile Tibial Tray is intended to be used with commercially available Triathlon® femoral components and associated patellar components, and tibial bearing inserts in

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primary cemented total knee arthroplasty. The indications for the Triathlon® Low Profile Tibial Tray are outlined below:

Indications for Use:

· Painful, disabling joint disease of the knee resulting from: degenerative arthritis, rheumatoid arthritis or post-traumatic arthritis.
· Post-traumatic loss of knee joint configuration and function.
· Moderate varus, valgus, or flexion deformity in which the ligamentous structures can be returned to adequate function and stability.

Indications for Use for the Triathlon Metal Backed Patella are:

. Noninflammatory degenerative joint disease including osteoarthritis, traumatic arthritis or avascular necrosis:
Rheumatoid arthritis; ●
Correction of functional deformity: ●
Revision procedures where other treatments or devices have failed; ●
Post traumatic loss of joint anatomy, particularly when there is patello-femoral erosion, . dysfunction or prior patellectomy; and,
Irreparable fracture of the knee. .

These products are intended to achieve fixation without the use of bone cement.

Indications for Use for the Triathlon PKR System are:

. 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.

Indications for Use for the Restoris MCK System:

The specific knee replacement configurations include:

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

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Restoris Multi Compartmental Knee is for single use only and is intended for implantation with bone cement.

Summary of Technological Characteristics: There have been no changes to the technological characteristics of the subject knee system devices as a result of the revision to the labeling. The subject devices have the same design and are manufactured from the same materials as the predicate devices.

Non-Clinical Testing:

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

Non-clinical testing as outlined in the FDA guidance document "Establishing Safety and Compatibility of Passive Implants in the Magnetic Resonance (MR) Environment - Guidance for Industry and FDA Staff', dated December 11, 2014 was conducted to characterize the compatibility of Stryker Orthopaedics partial/total knee passive implants in the MR environment. FDA guidance "Assessment of Radiofrequency-Induced Heating in the Magnetic Resonance (MR) Environment for Multi-Configuration Passive Medical Devices – Guidance for Industry and FDA Staff", dated March 22, 2016 was also consulted for the heating evaluations performed. Testing was performed according to the standards listed below:

Magnetically Inducted Displacement Force performed per ASTM F2052-15, Standard Test . Method for Measurement of Magnetically Induced Displacement Force on Medical Devices in the MR Environment
Magnetically Induced Torque - performed per ASTM F2213-06 (Reapproved 2011), Standard Test Method for Measurement of Magnetically Induced Torque on Medical Devices in the MR Environment
Image Artifact performed per ASTM F2119-07 (Reapproved 2013), Standard Test Method ● for Evaluation of MR Image Artifacts from passive Implants
. Heating by RF Fields per ASTM F2182-11a, Standard Test Method for Measurement of Radio Frequency Induced Heating near Passive Implants during MR Imaging

The labeling has been modified to include the MR conditional symbol, and to provide the parameters under which a patient who has the device can be safely scanned. Additionally, for certain devices, a contraindication was removed.

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

Conclusion: The Triathlon Knee System components, Triathlon PKR components and Restoris MCK components are substantially equivalent to the predicate devices identified in this premarket notification.

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.