510(k) Report

510(k) · Cleared

Cleared

Triathlon® Hinge Knee System

K251665510(k) TraditionalCleared Jul 25, 202556-day reviewClass II21 CFR 888.3510

Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly, last Nov 3, 2026

Howmedica Osteonics Corp., Dba Stryker Orthopaedics · KRO Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/Polymer

Cleared on Jul 25, 2025 as substantially equivalent to K230416 (Stryker, 2023) and 7 other predicates after a 56-day review. Its family tree reaches back 12 generations to 1994. 2 later devices descend from it.

Decided
Jul 25, 2025
Review
56 days
Class
Class II
Product code
KRO
Recalls
None
Predicates
8

Its longest line of descent runs back 12 generations to K943462 (1994). 97 ancestors in all, the oldest K811630 (1981). 2 later devices descend from it, 2 citing it directly.

Other ancestors, by year clearedDescendants, by year cleared 2023: 2 other ancestors2014: 1 other ancestor2006: 6 other ancestors2002: 6 other ancestors2000: 5 other ancestors2017: 1 other ancestor2015: 1 other ancestor2013: 3 other ancestors2008: 3 other ancestors2007: 6 other ancestors2005: 8 other ancestors2004: 9 other ancestors2003: 8 other ancestors1995: 3 other ancestors1991: 3 other ancestors1981: 1 other ancestor2010: 1 other ancestor1999: 2 other ancestors1998: 3 other ancestors1997: 3 other ancestors1996: 3 other ancestors1993: 1 other ancestor1990: 1 other ancestor2001: 4 other ancestors1988: 1 other ancestor2025: 1 descendant cleared2026: 1 descendant clearedK943462 · Darwin Knee System · Johnson & Johnson Professionals, Inc. · 1994 · recalled×2: 2 generations cleared close together, K033272 (2004), K040166 (2004) K061648 · Depuy Graduated Compartmental Knee (GCK) · DePuy Orthopaedics, Inc. · 2006 · recalledK070849 · Depuy GCK Femoral and Tibial Components · DePuy Orthopaedics, Inc. · 2007K082172 · Mako Modular Knee Compartmental Implant System · Mako Surgical Corporation · 2008 · recalledK090763 · Restoris Multicompartmental Knee (MCK) System · Mako Surgical Corporation · 2009 · recalledK133039 · Restoris Multicompartmental Knee System · Mako Surgical Corporation · 2013K150307 · RESTORIS Multicompartmental Knee System · Mako Surgical Corp. · 2015K172326 · Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee System · Stryker Orthopaedics · 2017 · recalled×2: 2 generations cleared close together, K223528 (2023), K230416 (2023) 19801990200020102020
Other ancestors, by generationDescendants, by generation 1 generation back: 6 other ancestors2 generations back: 23 other ancestors3 generations back: 18 other ancestors4 generations back: 12 other ancestors5 generations back: 17 other ancestors6 generations back: 9 other ancestors 1 generation forward: 2 descendants K230416 · Triathlon® Hinge Knee System; Triathlon® Revision Insert X3® · Stryker · 2023K223528 · Triathlon® Hinge Knee System · Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2023 · recalledK172326 · Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee System · Stryker Orthopaedics · 2017 · recalledK150307 · RESTORIS Multicompartmental Knee System · Mako Surgical Corp. · 2015K133039 · Restoris Multicompartmental Knee System · Mako Surgical Corporation · 2013K090763 · Restoris Multicompartmental Knee (MCK) System · Mako Surgical Corporation · 2009 · recalledK082172 · Mako Modular Knee Compartmental Implant System · Mako Surgical Corporation · 2008 · recalledK070849 · Depuy GCK Femoral and Tibial Components · DePuy Orthopaedics, Inc. · 2007K061648 · Depuy Graduated Compartmental Knee (GCK) · DePuy Orthopaedics, Inc. · 2006 · recalledK040166 · Depuy Sigma XLK Tibial Inserts · DePuy Orthopaedics, Inc. · 2004K033272 · Depuy Sigma Tibial Inserts · DePuy Orthopaedics, Inc. · 2004 · recalledK943462 · Darwin Knee System · Johnson & Johnson Professionals, Inc. · 1994 · recalled−10−50
  1. Root · 12 generations backK943462 Darwin Knee SystemJohnson & Johnson Professionals, Inc. · 1994 · Recalled
  2. 8 generations between
  3. 3 generations backK172326 Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee…Stryker Orthopaedics · 2017 · Recalled
  4. 2 generations backK223528 Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2023 · Recalled
  5. 1 generation backK230416 Triathlon® Hinge Knee System; Triathlon® Revision Insert X3®Stryker · 2023
  6. This deviceK251665 Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025
  7. Descendant · cites it directly · 0 of its ownK261898 Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total…Howmedica Osteonics Corp. dba Stryker Orthopaedics · 2026
  8. Descendant · cites it directly · 0 of its ownK252898 Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium®…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025 · Recalled
Show all 12 generations
  1. Root · 12 generations backK943462 Darwin Knee SystemJohnson & Johnson Professionals, Inc. · 1994 · Recalled
  2. 11 generations backK033272 Depuy Sigma Tibial InsertsDePuy Orthopaedics, Inc. · 2004 · Recalled
  3. 10 generations backK040166 Depuy Sigma XLK Tibial InsertsDePuy Orthopaedics, Inc. · 2004
  4. 9 generations backK061648 Depuy Graduated Compartmental Knee (GCK)DePuy Orthopaedics, Inc. · 2006 · Recalled
  5. 8 generations backK070849 Depuy GCK Femoral and Tibial ComponentsDePuy Orthopaedics, Inc. · 2007
  6. 7 generations backK082172 Mako Modular Knee Compartmental Implant SystemMako Surgical Corporation · 2008 · Recalled
  7. 6 generations backK090763 Restoris Multicompartmental Knee (MCK) SystemMako Surgical Corporation · 2009 · Recalled
  8. 5 generations backK133039 Restoris Multicompartmental Knee SystemMako Surgical Corporation · 2013
  9. 4 generations backK150307 RESTORIS Multicompartmental Knee SystemMako Surgical Corp. · 2015
  10. 3 generations backK172326 Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee…Stryker Orthopaedics · 2017 · Recalled
  11. 2 generations backK223528 Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2023 · Recalled
  12. 1 generation backK230416 Triathlon® Hinge Knee System; Triathlon® Revision Insert X3®Stryker · 2023
  13. This deviceK251665 Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025

Most influential descendants

Showing 2 of 2 · See all
  • K261898Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total Knee SystemHowmedica Osteonics Corp. dba Stryker Orthopaedics · 2026 · cites it directly0descendants
  • K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025 · cites it directly0descendants
View FIG. 1 as a table

Line of descent and top descendants

GenerationNumberDeviceApplicantDecidedRecalls
−12K943462Darwin Knee SystemJohnson & Johnson Professionals, Inc.19948
−11K033272Depuy Sigma Tibial InsertsDePuy Orthopaedics, Inc.200451
−10K040166Depuy Sigma XLK Tibial InsertsDePuy Orthopaedics, Inc.2004—
−9K061648Depuy Graduated Compartmental Knee (GCK)DePuy Orthopaedics, Inc.20061
−8K070849Depuy GCK Femoral and Tibial ComponentsDePuy Orthopaedics, Inc.2007—
−7K082172Mako Modular Knee Compartmental Implant SystemMako Surgical Corporation20082
−6K090763Restoris Multicompartmental Knee (MCK) SystemMako Surgical Corporation20095
−5K133039Restoris Multicompartmental Knee SystemMako Surgical Corporation2013—
−4K150307RESTORIS Multicompartmental Knee SystemMako Surgical Corp.2015—
−3K172326Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee SystemStryker Orthopaedics20171
−2K223528Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics20231
−1K230416Triathlon® Hinge Knee System; Triathlon® Revision Insert X3®Stryker2023—
0 (this device)K251665Triathlon® Hinge Knee SystemHowmedica Osteonics Corp., Dba Stryker Orthopaedics2025—
+1K261898Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total Knee SystemHowmedica Osteonics Corp. dba Stryker Orthopaedics2026—
+1K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric…Howmedica Osteonics Corp., Dba Stryker Orthopaedics20251

Other ancestors by year cleared

Year clearedDevicesWith a Class I recall
198110
198810
199010
199130
199310
199530
199630
199730
199830
199920
200050
200140
200260
200380
200490
200580
200660
200760
200830
201010
201330
201410
201510
201710
202320

Descendants by year cleared

Year clearedDevicesWith a Class I recall
202510
202610
FIG. 1 — Lineage of K251665, 1994–2026Source: FDA 510(k) summaries, read by 510(k) Report · How lineage is built

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Notable FDA decisions, review times and new Class I recalls. See an issue.

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. #1 K230416 Triathlon® Hinge Knee System; Triathlon®…score 17.4 · 11 generations · no Class I recall
  2. #2 Held for the reportin the report
  3. #3 Held for the reportin the report
Get a 510(k) Report

What was it cleared against? (8)

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.

TypeNumberDeviceApplicantDecidedRecalls
*K230416Triathlon® Hinge Knee System; Triathlon® Revision Insert X3®
Summary page 6
…KRO Legally Marketed Primary Predicate Device to which Substantial Equivalence is Claimed: ▪ Triathlon® Hinge Knee System; Triathlon® Revision Insert X3® - K230416 Legally Marketed Additional Predicate Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System…
Stryker2023—
*K053514Triathlon Total Knee System
Summary page 6
…iathlon® Revision Insert X3® - K230416 Legally Marketed Additional Predicate Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207,…
Stryker Orthopaedics20062
*K141056Triathlon Knee System Posterior Stabilized Components
Summary page 6
…Revision Insert X3® - K230416 Legally Marketed Additional Predicate Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552…
Stryker Orthopaedics201411
*K172326Triathlon Total Knee System, Triathlon PKR System, Restoris MCK Knee System
Summary page 6
…Insert X3® - K230416 Legally Marketed Additional Predicate Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552 Reason…
Stryker Orthopaedics20171
*K023087Global Modular Replacement System (GMRS)
Summary page 6
…redicate Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552 Reason for 510(k) Submission: The purpose of this Tradition…
Howmedica Osteonics Corp.20022
*K222056Global Modular Replacement System, Modular Replacement System, Modular Rotating Hinge Knee
Summary page 6
…Devices Used to Support Substantial Equivalence: ▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552 Reason for 510(k) Submission: The purpose of this Traditional 510(k)…
Howmedica Osteonics Corp., Dba Stryker Orthopaedics20231
*K994207Howmedica Osteonics Modular Rotating Hinge Knee
Summary page 6
…▪ Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552 Reason for 510(k) Submission: The purpose of this Traditional 510(k) Premarket Notification is to support the marketin…
Howmedica Osteonics Corp.2000—
*K002552Howmedica Osteonics Modular Rotating Hinge Knee
Summary page 6
…Triathlon® Total Knee System - K053514, K141056, K172326 ▪ GMRS Tibial Rotating Component - K023087, K222056 ▪ MRH Tibial Rotating Component- K994207, K002552 Reason for 510(k) Submission: The purpose of this Traditional 510(k) Premarket Notification is to support the marketing clearan…
Howmedica Osteonics Corp.2000—

Also cleared against K230416: 2 other devices →

What descends from it? (2)

2 later devices cite it directly; ranked here by how many devices descend from each in turn.

NumberDeviceApplicantDecidedDescendants
K261898Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total Knee SystemHowmedica Osteonics Corp. dba Stryker Orthopaedics20260
K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella…Howmedica Osteonics Corp., Dba Stryker Orthopaedics20250

Has anything in its family been recalled? (0 Class I)

No FDA recall names this device.

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 2.2 years on median.
  • 50 of the 97 ancestors have a recall of any class.
  • Of its descendants, K261898 (Howmedica Osteonics Corp. dba Stryker Orthopaedics, 2026) has gone furthest, with 0 descendants of its own.
  • 2 other devices also cite its predicate K230416.

How does its category compare?

All KRO devices

KRO 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

2007: 12008: 32009: 32010: 12011: 22012: 22013: 32014: 22015: 62016: 32017: 12019: 32020: 12021: 32022: 12023: 42024: 32025: 32026 (partial year): 1
2007high 6 (2015) · low 0 (2018)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · KRO

56in 2025

2008: 126 days median2009: 86 days median2013: 189 days median2015: 113 days median2016: 148 days median2019: 244 days median2021: 57 days median2023: 148 days median2024: 87 days median2025: 56 days median
2007high 244 (2019) · low 56 (2025)2026

Receipt to decision; years with fewer than 3 clearances left blank.

Recalls per year · KRO

14so far in 2026, the most since 2007

2007: 12008: 32009: 82011: 12012: 12013: 22015: 12016: 52017: 42018: 12021: 12025: 12026 (partial year): 14
2007high 14 (2026) · low 0 (2010)2026

Class I (0 since 2007) Class II/III not classified

Adverse event reports per year · KRO

915in 2025

2007: 372008: 442009: 662010: 1102011: 1192012: 1732013: 1942014: 4062015: 3332016: 3692017: 5432018: 6142019: 7592020: 7492021: 7702022: 8922023: 7462024: 8552025: 915
2007high 915 (2025) · low 37 (2007)2025

MAUDE reports naming product code KRO, not matched to any one device; reports are not rates.

View these four charts as a table
YearDecisionsMedian 510(k) review, daysRecalls (Class I)MAUDE reports
20071—137
20083126344
2009386866
20101—0110
20112—1119
20122—1173
201331892194
20142—0406
201561131333
201631485369
20171—4543
20180—1614
201932440759
20201—0749
20213571770
20221—0892
202341480746
20243870855
20253561915
20261—14—

What is it indicated for?

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…

Read the full statement (135 words)

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

Indications for use as stated in the FDA summary.

Also cleared against K230416

2 other devices cite the same predicate.

  • K261898Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total Knee SystemHowmedica Osteonics Corp. dba Stryker Orthopaedics · 2026
  • K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella; Triathlon® Symmetric…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 20251 recall

More from Howmedica Osteonics Corp., Dba Stryker…

31 FDA decisions under this applicant name. See the company

  • K261624Omnifit® 20° Series I Insert;Omnifit® Crossfire® 10° Series II Insert; Constrained Acetabular Insert…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 20262 recalls
  • K253637Triathlon® Total Knee System - Triathlon® X3® Medial Stabilized Tibial Bearing InsertHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2026
  • K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella; Triathlon® Symmetric…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 20251 recall
  • K252044Triathlon® Total Knee System - Triathlon® Gold Femoral ComponentsHowmedica Osteonics Corp., Dba Stryker Orthopaedics · 2025
  • K243817Scorpio Universal Dome Patella; Scorpio Total Stabilizer Insert; Scorpio-Flex Posterior Stabilized Tibial…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 20252 recalls

Recent decisions in KRO

The KRO category page

  • K261898Triathlon® Knee System; Triathlon® Hinge Knee System; Scorpio® Total Knee SystemHowmedica Osteonics Corp. dba Stryker Orthopaedics · 2026
  • K252898Triathlon® Tritanium® Asymmetric Patella; Triathlon® Tritanium® Symmetric Patella; Triathlon® Symmetric…Howmedica Osteonics Corp., Dba Stryker Orthopaedics · 20251 recall
  • K252303Stem Extension Line (USTAR II System)United Orthopedic Corporation · 2025
  • K242871ATTUNE™ Revision Hinge KneeDepuy Ireland UC · 202411 recalls
  • K240043EVOLUTION® Hinge Knee System;GUARDIAN™ limb Salvage System;DCW Modular Distal Femoral System;REPIPHYSIS™…Microport Orthopedics, Inc. · 2024

https://510kreport.com/device/K251665 · printed Nov 4, 2026

Cite this page

510(k) Report. “K251665: Triathlon® Hinge Knee System.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 4, 2026. https://510kreport.com/device/K251665

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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