510(k) Report

510(k) · Cleared

Cleared

Unicap Unicompartmental Knee Resurfacing Prosthesis

K050373510(k) TraditionalCleared Oct 11, 2005239-day reviewClass II21 CFR 888.3520

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

Arthrosurface, Inc. · HSX Prosthesis, Knee, Femorotibial, Non-Constrained, Cemented, Metal/Polymer

Cleared on Oct 11, 2005 as substantially equivalent to K880155 (Zimmer, Inc., 1988) and 3 other predicates after a 239-day review. Its family tree reaches back 2 generations to 1993. 2 later devices descend from it.

Decided
Oct 11, 2005
Review
239 days
Class
Class II
Product code
HSX
Recalls
None
Predicates
4

Its longest line of descent runs back 2 generations to K923011 (1993). 8 ancestors in all, the oldest K880155 (1988). 2 later devices descend from it, 1 citing it directly.

Other ancestors, by year clearedDescendants, by year cleared 2003: 1 other ancestor1996: 2 other ancestors1988: 1 other ancestor1999: 1 other ancestor1998: 1 other ancestor2023: 1 descendant cleared2024: 1 descendant clearedK923011 · Osteonics Unix Unicompartmental · Osteonics Corp. · 1993K033769 · Eius Unicompartmental Knee System · Howmedica Osteonics Corp. · 20041990200020102020
Other ancestors, by generationDescendants, by generation 1 generation back: 3 other ancestors2 generations back: 3 other ancestors 1 generation forward: 1 descendant2 generations forward: 1 descendant K033769 · Eius Unicompartmental Knee System · Howmedica Osteonics Corp. · 2004K923011 · Osteonics Unix Unicompartmental · Osteonics Corp. · 19930
  1. Root · 2 generations backK923011 Osteonics Unix UnicompartmentalOsteonics Corp. · 1993
  2. 1 generation backK033769 Eius Unicompartmental Knee SystemHowmedica Osteonics Corp. · 2004
  3. This deviceK050373 Unicap Unicompartmental Knee Resurfacing ProsthesisArthrosurface, Inc. · 2005
  4. Descendant · cites it directly · 1 of its ownK221292 Uni Knee Resurfacing SystemOverture Resurfacing, Inc. · 2023
  5. Descendant · 2 generations on · 0 of its ownK242746 OvertureTi Knee Resurfacing SystemTMOverture Orthopaedics · 2024

Most influential descendants

Showing 2 of 2 · See all
  • K221292Uni Knee Resurfacing SystemOverture Resurfacing, Inc. · 2023 · cites it directly1descendant
  • K242746OvertureTi Knee Resurfacing SystemTMOverture Orthopaedics · 2024 · 2 generations on0descendants
View FIG. 1 as a table

Line of descent and top descendants

GenerationNumberDeviceApplicantDecidedRecalls
−2K923011Osteonics Unix UnicompartmentalOsteonics Corp.1993—
−1K033769Eius Unicompartmental Knee SystemHowmedica Osteonics Corp.2004—
0 (this device)K050373Unicap Unicompartmental Knee Resurfacing ProsthesisArthrosurface, Inc.2005—
+1K221292Uni Knee Resurfacing SystemOverture Resurfacing, Inc.2023—
+2K242746OvertureTi Knee Resurfacing SystemTMOverture Orthopaedics2024—

Other ancestors by year cleared

Year clearedDevicesWith a Class I recall
198810
199620
199810
199910
200310

Descendants by year cleared

Year clearedDevicesWith a Class I recall
202310
202410
FIG. 1 — Lineage of K050373, 1993–2024Source: 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 HSX? 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 HSX device

  1. #1 K261609 Freedom Partial Knee Systemscore 15.1 · 12 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? (4)

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
*K880155Miller/Galante Precoat Unicompartmental Knee
Summary page 2
…llowing legally marketed devices to which the sponsor claims substantial equivalence: Miller/Galante Precoat Unicompartmental Knee System (Zimmer, Inc.) (K880155) Link® Endo-Model TM Sled Uni-Knee System, (Link America, Inc). (K954186) EUIS® Unicompartmental Knee Sys…
Zimmer, Inc.19881
*K954186Sled Unicompartment Knee System
Summary page 2
…Miller/Galante Precoat Unicompartmental Knee System (Zimmer, Inc.) (K880155) Link® Endo-Model TM Sled Uni-Knee System, (Link America, Inc). (K954186) EUIS® Unicompartmental Knee System (Howmedica Osteonics) (K033769) Stelkast Unicondylar Knee System (Ste…
Link America, Inc.199632
*K033769Eius Unicompartmental Knee System
Summary page 2
…80155) Link® Endo-Model TM Sled Uni-Knee System, (Link America, Inc). (K954186) EUIS® Unicompartmental Knee System (Howmedica Osteonics) (K033769) Stelkast Unicondylar Knee System (Stelkast Co.) (K032824) Device Description Summary The Unicompartmental Knee…
Howmedica Osteonics Corp.2004—
*K032824Stelkast Unicondylar Knee System
Summary page 2
…c). (K954186) EUIS® Unicompartmental Knee System (Howmedica Osteonics) (K033769) Stelkast Unicondylar Knee System (Stelkast Co.) (K032824) Device Description Summary The Unicompartmental Knee Resurfacing Prosthesis (UniCAPT M ) incorporates a low-profile femoral ar…
Stelkast Company20031

Also cleared against K880155: 4 other devices →

What descends from it? (2)

1 later device cites it directly; ranked here by how many devices descend from each in turn.

NumberDeviceApplicantDecidedDescendants
K221292Uni Knee Resurfacing SystemOverture Resurfacing, Inc.20231

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 12 years and passes through 3 companies; a new generation was cleared every 10.2 years on median.
  • 5 of the 8 ancestors have a recall of any class.
  • Of its descendants, K221292 (Overture Resurfacing, Inc., 2023) has gone furthest, with 1 descendant of its own.
  • 4 other devices also cite its predicate K880155.

How does its category compare?

All HSX devices

HSX Prosthesis, Knee, Femorotibial, Non-Constrained, Cemented, Metal/Polymer: FDA decisions, review times, recalls and adverse event reports over 20 years.

FDA decisions per year · HSX

4in 2025

2007: 62008: 42009: 22010: 32011: 12012: 52013: 22015: 12016: 32017: 52018: 22019: 72020: 42021: 72022: 22023: 12024: 42025: 42026 (partial year): 2
2007high 7 (2019) · low 0 (2014)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · HSX

59in 2025

2007: 33 days median2008: 102 days median2010: 74 days median2012: 88 days median2016: 147 days median2017: 160 days median2019: 90 days median2020: 40 days median2021: 81 days median2024: 133 days median2025: 59 days median
2007high 160 (2017) · low 33 (2007)2026

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

Recalls per year · HSX

2in 2020

2009: 492013: 12016: 12017: 42020: 2
2007high 49 (2009) · low 0 (2007)2026

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

Adverse event reports per year · HSX

175in 2025

2007: 62008: 42009: 212010: 582011: 1142012: 832013: 792014: 662015: 572016: 1072017: 1132018: 1592019: 1772020: 2732021: 2402022: 2572023: 2312024: 1722025: 175
2007high 273 (2020) · low 4 (2008)2025

MAUDE reports naming product code HSX, 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
200763306
2008410204
20092—4921
2010374058
20111—0114
2012588083
20132—179
20140—066
20151—057
201631471107
201751604113
20182—0159
20197900177
20204402273
20217810240
20222—0257
20231—0231
202441330172
20254590175
20262—0—

What is it indicated for?

The Unicompartmental Knee Resurfacing Prosthesis (UniCAP TM) is indicated for

use as a partial replacement of the articulating surfaces of the knee when only

one side of the joint is affected due to the compartmental primary degenerative or

post-traumatic degenerative disease, previous tibial condyle or plateau fractures,

deformity or revision of previous arthroplasty. This device is intended to be used

with bone cement.

Indications for use as stated in the FDA summary.

Also cleared against K880155

4 other devices cite the same predicate.

  • K161592Persona Partial Knee SystemBiomet, Inc. · 20162 recalls
  • K120262HLS Uni Evolution & U-KneetecTornier, Inc. · 2012
  • K081293Univation Unicondylar Knee SystemAesculap Implant Systems, Inc. · 20088 recalls
  • K033363Zimmer Unicompartmental Knee SystemZimmer, Inc. · 20043 recalls

More from Arthrosurface, Inc.

26 FDA decisions under this applicant name. See the company

  • K203375OVOMotion Reverse Shoulder Arthroplasty SystemArthrosurface, Inc. · 2021
  • K200718Arthrosurface WristMotion Total Wrist Arthroplasty SystemArthrosurface, Inc. · 2020
  • K190261BOSS Toe Fixation SystemArthrosurface, Inc. · 2019
  • K181280Patello-Femoral Wave (Kahuna) Arthroplasty SystemArthrosurface, Inc. · 20183 recalls
  • K173964OVOMotion Shoulder Arthroplasty SystemArthrosurface, Inc. · 2018

Recent decisions in HSX

The HSX category page

  • K261609Freedom Partial Knee SystemMaxx Orthopedics, Inc. · 2026
  • K260796Tahoe Unicondylar Knee System with TiNbN OvercoatShalby Advanced Technologies, Inc. Dba Consensus Orthopedics · 2026
  • K251771Cambridge Partial KneeSignature Orthopaedics Pty, Ltd. · 2025
  • K251834Persona Partial KneeZimmer Biomet · 2025
  • K251618MOTO Partial Knee System ExtensionMedacta International S.A. · 2025

https://510kreport.com/device/K050373 · printed Nov 6, 2026

Cite this page

510(k) Report. “K050373: Unicap Unicompartmental Knee Resurfacing Prosthesis.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K050373

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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