KRO · Class II · 21 CFR 888.3510

FDA Product Code KRO: Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/polymer

Constrained knee designs address the most challenging revision and deformity cases in orthopedic surgery. FDA product code KRO covers constrained cemented femorotibial knee prostheses.

These implants provide mechanical constraint of varus-valgus and rotational motion through a linked hinge or post-cam mechanism, compensating for severe ligamentous insufficiency that cannot be managed with less constrained designs.

KRO devices are Class II medical devices, regulated under 21 CFR 888.3510 and reviewed by the FDA Orthopedic panel.

Leading manufacturers include Howmedica Osteonics Corp., Dba Stryker Orthopaedics, Waldemar Link GmbH & Co. KG and Microport Orthopedics, Inc..

13
Total
13
Cleared
86d
Avg days
2021
Since

List of Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/polymer devices cleared through 510(k)

13 devices
1–13 of 13
Cleared Dec 15, 2025
Triathlon® Tritanium® Asymmetric Patella
K252898
Howmedica Osteonics Corp., Dba Stryker Orthopaedics
Orthopedic · 95d
Cleared Aug 22, 2025
Stem Extension Line (USTAR II System)
K252303
United Orthopedic Corporation
Orthopedic · 29d
Cleared Jul 25, 2025
Triathlon® Hinge Knee System
K251665
Howmedica Osteonics Corp., Dba Stryker Orthopaedics
Orthopedic · 56d
Cleared Nov 21, 2024
ATTUNE™ Revision Hinge Knee
K242871
Depuy Ireland UC
Orthopedic · 59d
Cleared Apr 01, 2024
EVOLUTION® Hinge Knee System
K240043
Microport Orthopedics, Inc.
Orthopedic · 87d
Cleared Mar 21, 2024
ATTUNE Total Knee System, ATTUNE Cementless Knee System, LPS Limb Preservation System, Sigma High Performance (HP) Partial Knee System
K233980
Depuy Ireland UC
Orthopedic · 94d
Cleared Sep 27, 2023
EVOLUTION® Hinge Knee System
K230563
Microport Orthopedics, Inc.
Orthopedic · 210d
Cleared May 19, 2023
Triathlon® Hinge Knee System
K230416
Stryker
Orthopedic · 92d
Cleared Apr 21, 2023
Modular Rotating Hinge Knee Systems and Compatible Components
K223069
Howmedica Osteonics Corp., Dba Stryker Orthopaedics
Orthopedic · 203d
Cleared Jan 20, 2023
Triathlon® Hinge Knee System
K223528
Howmedica Osteonics Corp., Dba Stryker Orthopaedics
Orthopedic · 58d
Cleared May 03, 2022
LINK Endo-Model EVO Knee System
K220628
Waldemar Link GmbH & Co. KG
Orthopedic · 60d
Cleared Jun 30, 2021
LINK Endo-Model Knee System, Femoral Segments (Augments), UHMWPE
K211768
Waldemar Link GmbH & Co. KG
Orthopedic · 22d
Cleared Mar 02, 2021
GMK Revision & Hinge Extension - TiNbN Coating
K210010
Medacta International S.A.
Orthopedic · 57d

How to use this database

This page lists all FDA 510(k) submissions for Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/polymer devices (product code KRO). Click any device to view full submission details, including the decision date, manufacturer information, predicate device, and a link to the official FDA record.

These devices fall under the Orthopedic FDA review panel. Browse all Orthopedic devices →