FDA product code · Orthopedic · Class 2
KRO: Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/Polymer
KRO is FDA's product code for "Prosthesis, Knee, Femorotibial, Constrained, Cemented, Metal/Polymer": a Class 2 device classified under 21 CFR 888.3510, reviewed by the Orthopedic panel. FDA flags it as an implant.
510(k) review time for KRO
Across 19 510(k) clearances under KRO decided from 2018-01-01 to 2026-10-06, the median was 87 days from FDA receipt to decision. Half took between 58 and 151 days, and 80% were decided within 206 days. These are past clearances, not a forecast for a new submission.
| Fastest | 22 |
|---|---|
| 25th percentile | 58 |
| Median | 87 |
| 75th percentile | 151 |
| 80th percentile | 206 |
| 90th percentile | 248 |
| Slowest | 437 |
Source: openFDA 510(k) records, snapshot of 2026-10-06 (openFDA data as of 2026-09-28). Compare 510(k) review times across all device types, see every code side by side in the Clearance Timeline Estimator, or browse the clearances themselves in PredicateScope.
KRO in the public FDA record
| 510(k) clearances, all years | 87 |
|---|---|
| Device recalls | 123 |
| Establishment listings | 580 |
| GUDID device identifiers | 6,436 |
Counts of records, not of devices or events. Adverse event reports for KRO are in MAUDEScope, as counts with the query shown: MAUDE has no denominator, so a report count is not a rate and does not show that a device caused an event.
FDA-recognized standards that cite KRO
29 FDA recognized consensus standards cite KRO, among them ASTM F983-86 (Reapproved 2018); ASTM F565-04 (Reapproved 2018); ISO 7207-1 Third edition 2007-02-01. Horizontal standards such as biocompatibility, sterilization and software standards can apply without citing the code.
- 11-197 ASTM F983-86 (Reapproved 2018) — Standard Practice for Permanent Marking of Orthopaedic Implant Components
- 11-199 ASTM F565-04 (Reapproved 2018) — Standard Practice for Care and Handling of Orthopedic Implants and Instruments
- 11-232 ISO 7207-1 Third edition 2007-02-01 — Implants for surgery - Components for partial and total knee joint prostheses - Part 1: Classification definitions and designation of dimensions
- 11-311 ISO 14243-2 Third edition 2016-09-01 — Implants for surgery - Wear of total knee-joint prostheses - Part 2: Methods of measurement
- 11-364 ISO 14243-1 Second edition 2009-11-15 — Implants for surgery - Wear of total knee-joint prostheses - Part 1: Loading and displacement parameters for wear-testing machines with load control and corresponding environmental conditions for test [Including AMENDMENT1 (2020)]
- 11-365 ASTM F1800-19 e1 — Standard Practice for Cyclic Fatigue Testing of Metal Tibial Tray Components of Total Knee Joint Replacements
- 11-366 ASTM F2381-19 — Standard Test Method for Evaluating Trans-Vinylene Yield in Irradiated Ultra-High Molecular Weight Polyethylene Fabricated Forms Intended for Surgical Implants by Infrared Spectroscopy
- 11-367 ISO 14243-3 Second edition 2014-11-01 — Implants for surgery - Wear of total knee-joint prostheses - Part 3: Loading and displacement parameters for wear-testing machines with displacement control and corresponding environmental conditions for test [Including AMENDMENT1 (2020)]
- 11-370 ISO 14879-1 Second edition 2020-07 — Implants for surgery - Total knee-joint prostheses - Part 1: Determination of endurance properties of knee tibial trays
- 11-373 ASTM F1223-20 — Standard Test Method for Determination of Total Knee Replacement Constraint
- 11-374 ISO 7207-2 Second edition 2011-07-01 — Implants for surgery - Components for partial and total knee joint prostheses - Part 2: Articulating surfaces made of metal ceramic and plastics materials [Including AMENDMENT 1 (2016) and AMENDMENT 2 (2020)]
- 11-395 ASTM F1814-22 — Standard Guide for Evaluating Modular Hip and Knee Joint Components
- 11-400 ISO 21536 Third edition 2023-07 — Non-active surgical implants - Joint replacement implants - Specific requirements for knee-joint replacement implants
- 11-406 ASTM F3141-23 — Standard Guide for Total Knee Replacement Loading Profiles
- 11-424 ASTM F983-24 — Standard Practice for Permanent Marking of Orthopaedic Implant Components
The first 15 of 29 are shown. Source: FDA Recognized Consensus Standards, snapshot of 2026-09-01. Search them all in the Consensus Standards Lookup.