510(k) · Cleared
Recalled · Class II · 2026Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella; Triathlon® Symmetric Patella; Triathlon® Asymmetric Patella; Scorpio® Universal Dome Patella; Triathlon® Hinge Bumper
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Howmedica Osteonics Corp., Dba Stryker Orthopaedics · KRO Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/Polymer
Cleared on Dec 15, 2025 as substantially equivalent to K242831 (Howmedica Osteonics Corp., Dba Stryker Orthopaedics, 2024) and 8 other predicates after a 95-day review. Its family tree reaches back 14 generations to 1994. It has been recalled once.
- Decided
- Dec 15, 2025
- Review
- 95 days
- Class
- Class II
- Product code
- KRO
- Recalls
- 1
- Predicates
- 9
Its longest line of descent runs back 14 generations to K943462 (1994). 114 ancestors in all, the oldest K811630 (1981). No later device cites it as a predicate yet.
- Root · 14 generations backK943462 Darwin Knee SystemJohnson & Johnson Professionals, Inc. · 1994 · Recalled
- 10 generations between
- 3 generations backK190402 Triathlon Total Knee System-Additional ComponentsStryker Orthopaedics (Aka Howmedica Osteonics Corp.) · 2019
- 2 generations backK230952 Triathlon® Total Knee System - Triathlon® Pro Posterior Stabilized…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2023
- 1 generation backK242831 Triathlon Knee System; Triathlon Pro Posterior Stabilized Femoral…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2024
- This deviceK252898 Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium®…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025
Show all 14 generations
- Root · 14 generations backK943462 Darwin Knee SystemJohnson & Johnson Professionals, Inc. · 1994 · Recalled
- 13 generations backK033272 Depuy Sigma Tibial InsertsDePuy Orthopaedics, Inc. · 2004 · Recalled
- 12 generations backK040166 Depuy Sigma XLK Tibial InsertsDePuy Orthopaedics, Inc. · 2004
- 11 generations backK061648 Depuy Graduated Compartmental Knee (GCK)DePuy Orthopaedics, Inc. · 2006 · Recalled
- 10 generations backK070849 Depuy GCK Femoral and Tibial ComponentsDePuy Orthopaedics, Inc. · 2007
- 9 generations backK082172 Mako Modular Knee Compartmental Implant SystemMako Surgical Corporation · 2008 · Recalled
- 8 generations backK090763 Restoris Multicompartmental Knee (MCK) SystemMako Surgical Corporation · 2009 · Recalled
- 7 generations backK133039 Restoris Multicompartmental Knee SystemMako Surgical Corporation · 2013
- 6 generations backK150307 RESTORIS Multicompartmental Knee SystemMako Surgical Corp. · 2015
- 5 generations backK172326 Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee…Stryker Orthopaedics · 2017 · Recalled
- 4 generations backK173849 Triathlon Total Knee SystemStryker Orthopaedics · 2018 · Recalled
- 3 generations backK190402 Triathlon Total Knee System-Additional ComponentsStryker Orthopaedics (Aka Howmedica Osteonics Corp.) · 2019
- 2 generations backK230952 Triathlon® Total Knee System - Triathlon® Pro Posterior Stabilized…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2023
- 1 generation backK242831 Triathlon Knee System; Triathlon Pro Posterior Stabilized Femoral…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2024
- This deviceK252898 Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium®…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −14 | K943462 | Darwin Knee System | Johnson & Johnson Professionals, Inc. | 1994 | 8 |
| −13 | K033272 | Depuy Sigma Tibial Inserts | DePuy Orthopaedics, Inc. | 2004 | 51 |
| −12 | K040166 | Depuy Sigma XLK Tibial Inserts | DePuy Orthopaedics, Inc. | 2004 | — |
| −11 | K061648 | Depuy Graduated Compartmental Knee (GCK) | DePuy Orthopaedics, Inc. | 2006 | 1 |
| −10 | K070849 | Depuy GCK Femoral and Tibial Components | DePuy Orthopaedics, Inc. | 2007 | — |
| −9 | K082172 | Mako Modular Knee Compartmental Implant System | Mako Surgical Corporation | 2008 | 2 |
| −8 | K090763 | Restoris Multicompartmental Knee (MCK) System | Mako Surgical Corporation | 2009 | 5 |
| −7 | K133039 | Restoris Multicompartmental Knee System | Mako Surgical Corporation | 2013 | — |
| −6 | K150307 | RESTORIS Multicompartmental Knee System | Mako Surgical Corp. | 2015 | — |
| −5 | K172326 | Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee System | Stryker Orthopaedics | 2017 | 1 |
| −4 | K173849 | Triathlon Total Knee System | Stryker Orthopaedics | 2018 | 3 |
| −3 | K190402 | Triathlon Total Knee System-Additional Components | Stryker Orthopaedics (Aka Howmedica Osteonics Corp.) | 2019 | — |
| −2 | K230952 | Triathlon® Total Knee System - Triathlon® Pro Posterior Stabilized (PS)… | Howmedica Osteonics Corp., Dba Stryker Orthopaedics | 2023 | — |
| −1 | K242831 | Triathlon Knee System; Triathlon Pro Posterior Stabilized Femoral Components… | Howmedica Osteonics Corp., Dba Stryker Orthopaedics | 2024 | — |
| 0 (this device) | K252898 | Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric… | Howmedica Osteonics Corp., Dba Stryker Orthopaedics | 2025 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1981 | 1 | 0 |
| 1988 | 1 | 0 |
| 1990 | 1 | 0 |
| 1991 | 3 | 0 |
| 1992 | 2 | 0 |
| 1993 | 2 | 0 |
| 1995 | 3 | 0 |
| 1996 | 3 | 0 |
| 1997 | 3 | 0 |
| 1998 | 4 | 0 |
| 1999 | 2 | 0 |
| 2000 | 6 | 0 |
| 2001 | 5 | 0 |
| 2002 | 6 | 0 |
| 2003 | 9 | 0 |
| 2004 | 10 | 0 |
| 2005 | 10 | 0 |
| 2006 | 6 | 0 |
| 2007 | 6 | 0 |
| 2008 | 3 | 0 |
| 2010 | 1 | 0 |
| 2013 | 3 | 0 |
| 2014 | 1 | 0 |
| 2015 | 1 | 0 |
| 2017 | 1 | 0 |
| 2021 | 1 | 0 |
| 2023 | 4 | 0 |
| 2025 | 2 | 0 |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in KRO? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new KRO device
- #1 K251665 Triathlon® Hinge Knee Systemscore 19.0 · 12 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (9)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K242831 | Triathlon Knee System; Triathlon Pro Posterior Stabilized Femoral Components; Triathlon…Summary page 7…K252898 - Page 2 of 4 Legally Marketed Predicate Device to Which Substantial Equivalence is Claimed: The primary predicate for this submission is K242831. Legally Marketed Additional Predicate Devices Device Previous Premarket Notif… | 2024 |
| * | K132624 | Triathlon Tritanium Metal-Backed PatellaSummary page 7…Device Previous Premarket Notifications Triathlon® Tritanium® Asymmetric Patella K132624, K141056 ® ® Triathlon Tritanium Symmetric Patella Triathlon® Symmetric Patella… | 2013 |
| * | K141056 | Triathlon Knee System Posterior Stabilized ComponentsSummary page 7…Device Previous Premarket Notifications Triathlon® Tritanium® Asymmetric Patella K132624, K141056 ® ® Triathlon Tritanium Symmetric Patella Triathlon® Symmetric Patella… | 2014 |
| * | K040267 | Triathlon Cruciate Retaining (CR) Total KneeSummary page 7…K132624, K141056 ® ® Triathlon Tritanium Symmetric Patella Triathlon® Symmetric Patella K040267, K141056 ® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlo… | 2004 |
| * | K972967 | Osteonics Scorpio Total Knee Universal Dome Patellar Component;Osteonics Scorpio Total…Summary page 7…tric Patella K040267, K141056 ® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlon® Hinge Bumper K223528, K230416, K251665 Rationale for Bundling: The change propose… | 1998 |
| * | K243817 | Scorpio Universal Dome Patella; Scorpio Total Stabilizer Insert; Scorpio-Flex Posterior…Summary page 7…lla K040267, K141056 ® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlon® Hinge Bumper K223528, K230416, K251665 Rationale for Bundling: The change proposed is only… | 2025 |
| * | K223528 | Triathlon® Hinge Knee SystemSummary page 7…7, K141056 ® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlon® Hinge Bumper K223528, K230416, K251665 Rationale for Bundling: The change proposed is only related to updating the packaging configuration of the Ul… | 2023 |
| * | K230416 | Triathlon® Hinge Knee System; Triathlon® Revision Insert X3®Summary page 7…6 ® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlon® Hinge Bumper K223528, K230416, K251665 Rationale for Bundling: The change proposed is only related to updating the packaging configuration of the Ultra High… | 2023 |
| * | K251665 | Triathlon® Hinge Knee SystemSummary page 7…® Triathlon Asymmetric Patella Scorpio® Universal Dome Patella K972967, K243817 Triathlon® Hinge Bumper K223528, K230416, K251665 Rationale for Bundling: The change proposed is only related to updating the packaging configuration of the Ultra High Molecular… | 2025 |
What descends from it?
No later submission names this one as a predicate yet.
Has anything in its family been recalled? (0 Class I)
Recalls of this device
| Date | Class | Recall | Root cause | Reason |
|---|---|---|---|---|
| Jul 30, 2026 | Class II | Z-3206-2026 | Process change control | Affected devices were manufactured with Ultra High Molecular Weight Polyethylene (UHMWPE) raw material aged in excess of five years. Product has the potential for elevated levels of oxidation, which may result in increased wear, leading… |
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 31 years and passes through 7 companies; a new generation was cleared every 1.5 years on median.
- 59 of the 114 ancestors have a recall of any class.
- 2 other devices also cite its predicate K242831.
How does its category compare?
All KRO devicesKRO Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/Polymer: FDA decisions, review times, recalls and adverse event reports over 20 years. 2025, this device’s year, is highlighted.
FDA decisions per year · KRO
3in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · KRO
56in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · KRO
14so far in 2026, the most since 2007
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · KRO
915in 2025
MAUDE reports naming product code KRO, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 1 | — | 1 | 37 |
| 2008 | 3 | 126 | 3 | 44 |
| 2009 | 3 | 86 | 8 | 66 |
| 2010 | 1 | — | 0 | 110 |
| 2011 | 2 | — | 1 | 119 |
| 2012 | 2 | — | 1 | 173 |
| 2013 | 3 | 189 | 2 | 194 |
| 2014 | 2 | — | 0 | 406 |
| 2015 | 6 | 113 | 1 | 333 |
| 2016 | 3 | 148 | 5 | 369 |
| 2017 | 1 | — | 4 | 543 |
| 2018 | 0 | — | 1 | 614 |
| 2019 | 3 | 244 | 0 | 759 |
| 2020 | 1 | — | 0 | 749 |
| 2021 | 3 | 57 | 1 | 770 |
| 2022 | 1 | — | 0 | 892 |
| 2023 | 4 | 148 | 0 | 746 |
| 2024 | 3 | 87 | 0 | 855 |
| 2025 | 3 | 56 | 1 | 915 |
| 2026 | 1 | — | 14 | — |
What is it indicated for?
Triathlon® Symmetric and Asymmetric Patella • 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…
Read the full statement (393 words)
Triathlon® Symmetric and Asymmetric Patella
• 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.
Triathlon® Tritanium® Asymmetric and Symmetric Patella
• 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 Tibial Baseplate and Tritanium Metal-Backed Patella components are indicated for both uncemented and cemented use.
Triathlon® Hinge Bumper
Triathlon® Hinge Knee System is intended to be implanted with bone cement for the following condition(s):
• There is destruction of the joint surfaces, with or without significant bone deformity.
• The cruciate and/or collateral ligaments do not stabilize the knee joint.
• The ligaments are inadequate and/or the musculature is weak. And/or
• Revision is required of a failed prosthesis where there has been gross instability, with or without bone loss or inadequate soft tissue.
When used with MRH femur and/or MRH tibial baseplate replacement indicated in revision of an existing prosthesis:
• Revision is required of a failed prosthesis where there has been gross instability, with or without bone loss or inadequate soft tissue.
When used with compatible GMRS components:
• Where segmental resection and/or replacement of femur and/or proximal tibia is required.
Scorpio® Universal Dome Patella
• 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.
• Revision of previous unsuccessful knee replacement or other procedure.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K252898 · printed Nov 4, 2026
Cite this page
510(k) Report. “K252898: Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella; Triathlon® Symmetric Patella; Triathlon® Asymmetric Patella; Scorpio® Universal Dome Patella; Triathlon® Hinge Bumper.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 4, 2026. https://510kreport.com/device/K252898
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026