510(k) · Cleared
ClearedStem Extension Line (U2 Total Knee System—PSA Type)
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
United Orthopedic Corporation · JWH Prosthesis, Knee, Patellofemorotibial, Semi-Constrained, Cemented, Polymer/Metal/Polymer
Cleared on Sep 25, 2025 as substantially equivalent to K082424 (United Orthopedic Corp., 2008) after a 28-day review. Its family tree reaches back 3 generations to 2002.
- Decided
- Sep 25, 2025
- Review
- 28 days
- Class
- Class II
- Product code
- JWH
- Recalls
- None
- Predicates
- 1
Its longest line of descent runs back 3 generations to K021657 (2002). 4 ancestors in all, the oldest K960279 (1996). No later device cites it as a predicate yet.
- Root · 3 generations backK021657 Uknee Total Knee SystemUnited Orthopedic Corp. · 2002
- 2 generations backK051640 U2 Total Knee SystemUnited Orthopedic Corp. · 2006 · Recalled
- 1 generation backK082424 United U2 Total Knee SystemUnited Orthopedic Corp. · 2008 · Recalled
- This deviceK252725 Stem Extension Line (U2 Total Knee System—PSA Type)United Orthopedic Corporation · 2025
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −3 | K021657 | Uknee Total Knee System | United Orthopedic Corp. | 2002 | — |
| −2 | K051640 | U2 Total Knee System | United Orthopedic Corp. | 2006 | 1 |
| −1 | K082424 | United U2 Total Knee System | United Orthopedic Corp. | 2008 | 2 |
| 0 (this device) | K252725 | Stem Extension Line (U2 Total Knee System—PSA Type) | United Orthopedic Corporation | 2025 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1996 | 1 | 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 JWH? 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 JWH device
- #1 K221479 Persona Personalized Knee Systemscore 22.4 · 11 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (1)
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 |
|---|---|---|---|
| * | K082424 | United U2 Total Knee SystemSummary page 5…Product Codes JWH Legally Marketed Predicate Devices Predicate Predicate Trade Name Product Code K082424 U2 Total Knee System—PSA Type JWH Device Description “UNITED” U2 Total Knee System – Pos… | 2008 |
What descends from it?
No later submission names this one as a predicate yet.
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 23 years and passes through 2 companies; a new generation was cleared every 3.6 years on median.
- 3 of the 4 ancestors have a recall of any class.
- 8 other devices also cite its predicate K082424.
How does its category compare?
All JWH devicesJWH Prosthesis, Knee, Patellofemorotibial, Semi-Constrained, Cemented, Polymer/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 · JWH
20in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · JWH
55in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · JWH
2in 2025
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · JWH
9,306in 2025
MAUDE reports naming product code JWH, 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 | 18 | 74 | 14 | 1,305 |
| 2008 | 17 | 81 | 10 | 1,483 |
| 2009 | 11 | 168 | 109 | 1,870 |
| 2010 | 19 | 85 | 32 | 3,286 |
| 2011 | 25 | 87 | 27 | 5,133 |
| 2012 | 33 | 85 | 85 | 5,203 |
| 2013 | 31 | 128 | 31 | 6,135 |
| 2014 | 33 | 98 | 13 | 6,722 |
| 2015 | 27 | 87 | 11 | 6,881 |
| 2016 | 18 | 88 | 17 | 7,586 |
| 2017 | 25 | 118 | 61 | 12,263 |
| 2018 | 25 | 90 | 14 | 14,071 |
| 2019 | 28 | 133 | 5 | 14,987 |
| 2020 | 22 | 59 | 2 | 12,592 |
| 2021 | 24 | 61 | 8 | 9,408 |
| 2022 | 17 | 56 | 12 | 8,364 |
| 2023 | 20 | 57 | 67 | 8,947 |
| 2024 | 19 | 89 | 7 | 10,828 |
| 2025 | 20 | 55 | 2 | 9,306 |
| 2026 | 12 | 63 | 4 | — |
What is it indicated for?
This device is indicated in knee arthroplasty in skeletally mature patients with severe knee pain and disability due to rheumatoid arthritis, osteoarthritis, primary and secondary traumatic arthritis, polyarthritis, collagen disorders, avascular necrosis of the femoral condyle or pseudogout, posttraumatic loss of joint configuration, particularly when there is patellofemoral joint surface erosion, dysfunction or prior patellectomy, moderate valgus…
Read the full statement (122 words)
This device is indicated in knee arthroplasty in skeletally mature patients with severe knee pain and disability due to rheumatoid arthritis, osteoarthritis, primary and secondary traumatic arthritis, polyarthritis, collagen disorders, avascular necrosis of the femoral condyle or pseudogout, posttraumatic loss of joint configuration, particularly when there is patellofemoral joint surface erosion, dysfunction or prior patellectomy, moderate valgus, varus, or flexion contraction. This device is intended for use in patients who require augmentation and/or stem extensions due to inadequate bone stock and/or require increased stabilization for tibiofemoral joint due to soft tissue imbalance. The femoral and tibial augments are to be attached to their respective components with a fixation screw or screws.
Note: In the US, this device is for cemented use only.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K252725 · printed Nov 6, 2026
Cite this page
510(k) Report. “K252725: Stem Extension Line (U2 Total Knee System—PSA Type).” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K252725
Report an extraction error
Are you the manufacturer?
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