The Kinemax® Superstabilizer (K904208), Kinematic® II Modular Condylar and Stabilizer Inserts (K871349), PCA® Modular Inserts (K894403), Kinematio® Rotating Hinge Knee (K792089), Duracon® Unicompartmental Knee (K 926231), and the Modular Replacement Metal Encapsulated Components (K952970) are intended to be used with the PCA®, Duracon®, or Kinemax® family of femoral components, tibial baseplates, and patellar components in primary or revision cemented total knee arthroplasty.
Device Story
Duration® Stabilized UHMWPE knee components are orthopedic implants designed for primary or revision cemented total knee arthroplasty. The device utilizes a proprietary sterilization process (Duration® Stabilized) as an alternative to standard air-irradiated gamma sterilization to improve wear resistance. Components are intended for use with existing Howmedica knee systems (PCA®, Duracon®, Kinemax®). The device is implanted by orthopedic surgeons in a clinical/hospital setting. The primary benefit is reduced volumetric wear of the polyethylene component, potentially extending implant longevity. Clinical decision-making is supported by in vitro wear testing data demonstrating reduced wear rates compared to conventionally sterilized UHMWPE.
Clinical Evidence
Bench testing only. Three in vitro wear studies were conducted: 1) Reciprocating ring-on-block test (5 million cycles) showed 30% reduction in volumetric wear; 2) Reciprocating pin-on-disk test (4 million cycles) showed 68% reduction; 3) Reciprocating pin-on-disk test on aged samples (2.5 million cycles, simulated 7-9 years aging) showed 91% reduction. All tests used CoCr counterfaces and bovine calf serum lubricant. No clinical data provided; in vitro results not shown to correlate with clinical wear mechanisms.
Technological Characteristics
Material: Ultra-High Molecular Weight Polyethylene (UHMWPE). Sterilization: Duration® Stabilized process (alternate to standard air-irradiated gamma). Components are designed for cemented fixation only. Mechanical testing performed via reciprocating ring-on-block and pin-on-disk wear evaluations.
Indications for Use
Indicated for patients undergoing primary or revision cemented total knee arthroplasty. Intended for use with specific Howmedica femoral components, tibial baseplates, and patellar components. Contraindicated for non-cemented fixation.
Regulatory Classification
Identification
A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device limits translation and rotation in one or more planes via the geometry of its articulating surfaces. It has no linkage across-the-joint. This generic type of device includes prostheses that have a femoral component made of alloys, such as cobalt-chromium-molybdenum, and a tibial component or components and a retropatellar resurfacing component made of ultra-high molecular weight polyethylene. This generic type of device is limited to those prostheses intended for use with bone cement (§ 888.3027).
Modular Replacement Metal Encapsulated Components (K952970)
Submission Summary (Full Text)
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K97 2863
## 510(k) Summary
Proprietary Name: Duration® Stabilized UHMWPE Knee Components
Common Name: UHMWPE Knee Components
OCT 29 1997
21 CFR 888.3560 Classification Name and Reference:
Proposed Requiatory Class: Class II Device Product Code: JWH
For information contact: Frank Maas Manager, Regulatory Affairs Howmedica Inc. 359 Veterans Boulevard Rutherford, NJ 07070 Telephone: (201) 507-7875 (201) 507-6870 Fax: Date Summary Prepared: 8-1-97
This submission describes additional UHMWPE Knee components that can be sterilized by the Duration® Stabilized process previously cleared in submission K936292, as an alternate to standard air irradiated gamma sterilization. Corresponding wear claims, previously cleared in submission K 965173 and listed below, are also applicable to these additional components.
This submission includes the Kinemax® Superstabilizer (K904208), the Kinematic® II Modular Condylar and Stabilizer Inserts (K871349), the PCA Modular Inserts(K894403), the Kinematic® Rotating Hinge Knee (K792089), the Duracon® Unicompartmental Knee (K926231), and the Modular Replacement Metal Encapsulated Components (K952970). These components are intended to be used with the PCA®, Duracon®, or Kinemax® family of femoral components, tibial baseplates, and patellar components in primary or revision cemented total knee arthroplasty.
Following are the wear claims that will be made for these devices:
A block of Howmedica's Duration® Stabilized UHMWPE showed a 30% reduction in volumetric wear versus the same block of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating ring-on-block wear test for over 5 million cycles, using a circular disk, 2.83" in diameter, 1" wide, CoCr articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
{1}------------------------------------------------
In an independent laboratory test, a 9mm thick circular disk of Howmedica's Duration® Stabilized UHMWPE showed a 68% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating pin-on-disk wear evaluation over 4 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration® Stabilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging", showed a 91% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging". Testing was performed in a reciprocating pin-on-disk wear evaluations over 2.5 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
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## DEPARTMENT OF HEALTH & HUMAN SERVICES
Image /page/2/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo consists of a circular seal with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized image of an eagle with its wings spread.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
Mr. Frank Maas Requlatory Affairs Manager Howmedica, Inc. Pfizer Hospital Products Group 359 Veterans Boulevard Rutherford, New Jersey 07070-2584
OCT 2 9 1997
K972863 Re: Duration® Stabilized UHMWPE Trade Name: Knee Components Requlatory Class: II Product Code: JWH Dated: August 1, 1997 Received: August 4, 1997
Dear Mr. Maas:
We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). This decision is based on this device being equivalent only to similar devices labeled and intended to be fixed within bone with acrylic "bone cement." You may, therefore, market your device subject to the general controls provisions of the Act and the following limitations:
- This device may not be labeled or promoted for non-1. cemented use.
- All labeling for this device, including package label 2. and labeling included within the package, must prominently state that the device is intended for cemented use only.
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### Page 2 - Mr. Frank Maas
- Any non-cemented fixation of this device is considered 3. investigational and may only be investigated as a significant risk device in accordance with the investigational device exemption (IDE) regulation under 21 CFR, Part 812. All users of the device for noncemented fixation must receive approval from their respective institutional review boards (IRBs) and the Food and Drug Administration (FDA) to conduct the investigation.
The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practices, labeling, and prohibitions against misbranding and adulteration.
If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP requlation may result in regulatory In addition, FDA may publish further announcements action. concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal Laws or Requlations.
This letter will allow you to begin marketing your device as described in your 510(k) premarket notification immediately. An FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and permits your device to proceed to the market.
If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to
premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be
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Page 3 - Mr. Frank Maas
obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address "http://www.fda.gov/cdrh/dsmamain.html".
Sincerely yours,
Celia M. Witten, Ph.D., M.D.
Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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K972863
# DURATION® WEAR CLAIMS - KNEE COMPONENTS
A block of Howmedica's Duration® Stabilized UHMWPE showed a 30% reduction in volumetric wear versus the same block of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating ring-on-block wear test for over 5 million cycles, using a circular disk, 2.83" in diameter, 1" wide, CoCr articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration® Stabilized UHMWPE showed a 68% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE. Testing was performed in a reciprocating pin-on-disk wear evaluation over 4 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
In an independent laboratory test, a 9 mm thick circular disk of Howmedica's Duration® Stabilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging", showed a 91% reduction in volumetric wear versus the same circular disk of Howmedica's conventionally gamma sterilized UHMWPE, having undergone 23 days of heating in air to simulate 7-9 years of "aging". Testing was performed in a reciprocating pin-on-disk wear evaluations over 2.5 million cycles, using a CoCr cylindrical pin with a 1" spherical end as the articulating counterface and bovine calf serum as a lubricant. The results of in vitro tests have not been shown to correlate with clinical wear mechanisms.
Prescription Use
(Per 21 CFR 801.109)
ACotter
Sign-Off of General Restorative (k) Number
{6}------------------------------------------------
Indications for Use
K972863
510(k) Number (if known):
Device Name: Duration® Stabilized UHMWPE Knee Components
Indications for Use:
The Kinemax® Superstabilizer (K904208), Kinematic® II Modular Condylar and Stabilizer Inserts (K871349), PCA® Modular Inserts (K894403), Kinematio® Rotating Hinge Knee (K792089), Duracon® Unicompartmental Knee (K 926231), and the Modular Replacement Metal Encapsulated Components (K952970) are intended to be used with the PCA®, Duracon®, or Kinemax® family of femoral components, tibial baseplates, and patellar components in primary or revision cemented total knee arthroplasty.
SEE NEXT PAGE FOR DURATION® WEAR CLAIMS
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
| Prescription Use | <div style="text-align:left;">X</div> | OR | Over-The-Counter Use | |
|----------------------|---------------------------------------|----|----------------------|--|
| (Per 21 CFR 801.109) | | | | |
(Division Sign-Off)
Division of General Restorative Devices
(Optional Format 1-2-96)
| 510(k) Number | K972863 |
|---------------|---------|
|---------------|---------|
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Part 1 — Search, results, and everyday workflows 16 min
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1. Search: exact and fuzzy
Type a phrase like "coronary artery calcification" into the search box. You get two kinds of results. Exact results match the literal phrase — prefix searches work ("coronary artery calcificati") but suffix searches do not. Fuzzy results match on the meaning and intent of your phrase rather than the exact words, and are sorted by relevance score. Hover over the Exact or Fuzzy badge on any row to see exactly why it matched.
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Exact vs. fuzzy search: what's the difference?
Exact matches on the literal phrase (prefix search works, suffix does not). Fuzzy matches on the meaning and intent of the phrase rather than the exact words. Hover over the badge on any row to see why it matched.
You search "coronary artery calcification" and want only software devices with AI. What two filters do you apply?
Narrow by SaMD (software-only devices), then narrow by AI/ML (devices with AI).
2. The results table
Scroll right in the results table. The intended use is extracted for you — no need to open the PDF. The device story gives a high-level snapshot of what the device does and how it's used. The AI Performance sub-table shows each output name, acceptance criteria, observed values, and development/test dataset descriptions — the same format Innolitics uses for regulatory strategy outputs, and the fastest high-level fingerprint of an AI device. It is AI-generated but has been very reliable in practice.
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Scroll right in the search results table. The intended use column is extracted for you; no need to dig into the 510(k) summary PDF.
What does the AI Performance sub-table show, and why is it useful?
Output name, acceptance criteria, observed values, development dataset description, and test dataset description. It's the same format we use for regulatory strategy output and Fast 510(k) input, and the fastest high-level fingerprint of an AI device. AI-generated but reliable in practice.
3. Judging fuzzy relevance
Fuzzy results trail off in relevance as you scroll. Use three signals to decide how far down to go: the fuzzy badge explanations, the intended use column, and whether your target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, you're past the relevant zone. A top hit with a low score (~0.4) and a stretched explanation is a hint the closest predicates are far away — the project may be headed for De Novo. Note the fuzzy search is a pattern match: it doesn't handle negation ("not") well, and hardware devices can appear — filter by SaMD/AI ML to cut them.
How do you judge how far down fuzzy search results to go?
Use the relevancy signals: the fuzzy badge explanations, the intended use column, and whether the target output (e.g., Cobb angle) still appears in the AI Performance sub-table. Once it stops appearing, results are trailing off in relevancy.
4. Device detail page: chat and citations
Click a device name to open its detail page: device facts on the left, a chat window on the right. Ask something like "Describe the training data". The answer carries little citation bubbles — click one to jump to the highlighted passage in the source PDF, so you can verify every AI answer against the document. There's also a Download PDF button for sharing.
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Reading rule for every project: how many summaries do you read in full?
At least the three most relevant 510(k) or De Novo summaries, in full. After that, use targeted chat questions to confirm your memory quickly. The tool supports this professional habit — it doesn't replace it.
5. Side-by-side comparison
Select multiple rows in the results table (aim for under ~10), then open the PDF Viewer tab. Ask one question — it goes to all selected devices in parallel, each with citations. This is the fastest way to compare and contrast devices: training data, PCCP scope, how they handled adding new scanners, and so on.
What does the side-by-side PDF viewer mode do?
Select multiple devices, open the PDF viewer tab, and ask one question (e.g., "Describe the training data"). It queries all selected devices simultaneously with citations, so you can compare and contrast quickly.
6. Collections
With rows selected, go to the Collections tab and create a labeled collection (e.g., "Cobb Angle Project"). Reload that selection any time — before a client call, pull up the collection and ask questions across all of its devices at once.
How do you save a set of selected devices for later use?
Select the rows, go to the Collections tab, and create a labeled collection (e.g., "Cobb Angle Project"). You can reload the selection anytime and carry it into the PDF viewer and other tabs that support selections.
7. Product codes and the regulations tree
Click a product code in the results to jump to it in the regulations tree — identification text, sibling product codes, and devices you can open in a PDF viewer on the right. Click a regulation number to see its identification, special controls, and related product codes. You can also search by product code or regulation number at the top of the tree. Always read the special controls if any exist for your device — it broadens your search and sharpens pre-kickoff research.
What can you do from the regulations tree view?
Browse product codes and regulation numbers, read the identification text and special controls, browse sibling product codes, open device PDFs on the right, and search by product code or regulation number at the top of the tree.
8. Chart view
Click Show Chart and segment by regulation number (or product code) to see which regulations dominate your result set. Clicking a regulation takes you into the regulations tree. Great for spotting that most matches are, say, hardware laparoscopic devices — a cue to go back and filter.
How do you see which regulations dominate a search result set?
Click "Show Chart" and segment by Regulation Number. Clicking a regulation takes you to the regulations tree.
9. The predicate graph
Open the Predicates tab for a family-tree view of predicate relationships. Click a node to trace its parents and children; selections from search carry over pre-selected. Commonly predicated devices are worth reading — a lot of people predicated them for a reason. The visual lineage is also handy on client calls, e.g. to show how a predicate family evolved and justify why your predicate still holds.
In the predicate graph, why are commonly predicated devices worth reading?
A lot of people predicated them for a reason. Clicking a node traces parents and children, and selections from search carry over pre-selected.
10. Embeddings: the galaxy map
The Embeddings tab plots every matching document in a 2-D "galaxy map" where semantically similar devices cluster together. Hover or click clusters to explore, and let AI label the clusters for you. Embeddings beat product codes for grouping: two devices can carry different product codes (LLZ vs. QIH) yet do the same thing — the embedding captures the meaning of the intended use and device story. This is also exactly how retrieval-augmented generation (RAG) works under the hood, and it makes a great visual on client calls.
Try it yourself
Head to the search page and work through a few of these AI/ML fuzzy searches to build intuition: perivascular fat on CT · aortic valve calcification opportunistic screening on noncontrast CT · breast cancer prediction on digital pathology slides · autism detection · gestational age prediction · a hearing aid that can also detect a pulse · foundation model based analysis of ECG · large language models · penetration test. Watch how the relevance scores, intended use, and AI Performance tables tell you when results stop being meaningful.