The P.F.C. Sigma Porous Modular Keel Tibial Tray is indicated for use in total knee replacements of patients suffering from severe pain and disability due to permanent structural damage in the knee joint from rheumatoid arthritis, osteoarthritis, post-traumatic arthritis, collagen disorders, or pseudogout. This damage may also be the result of trauma or failed prior surgical intervention.

In accordance with Federal (USA) requirements, the P.F.C. Sigma Knee Modular Keel Tibial Tray is indicated for use only with PMMA bone cement.

Device Description

The P.F.C. Sigma Porous Modular Keel Tibial Tray is manufactured from titanium alloy (Ti-6Al-4V). The distal surface, including approximately one-third of the stem and P.F.C. Sigma Porous Modular Keel Tibial Tray portions, is coated with commercially pure titanium porous coating to enhance cement fixation. If additional fixation is required, the tibial tray is designed with four screw holes that accept bone screws.

The distal tip of the P.F.C. Sigma Porous Modular Keel Tibial Tray is manufactured with a UHMWPE plug. When a long stem device is required the UHMWPE plug is removed to allow the tibial tray to accept attachment of a metallic extension.

The P.F.C. Sigma Porous Modular Keel Tibial Tray is designed for use with both P.F.C. Modular and P.F.C. Sigma tibial inserts, including curved posterior lipped and stabilized.

AI/ML Overview

The provided text describes a 510(k) summary for a medical device called the "P.F.C. Sigma Porous Modular Keel Tibial Tray." It primarily focuses on the device's description, indications for use, and a demonstration of substantial equivalence to previously marketed devices. This type of submission (510(k)) does not typically include a detailed "study" in the sense of a clinical trial with acceptance criteria and reported performance in the manner one might expect for a novel drug or a high-risk medical device with complex performance metrics.

Instead, the "acceptance criteria" and "study" for a Class II knee prosthesis like this, under a 510(k) pathway, usually revolve around demonstrating substantial equivalence to a predicate device. This is achieved through:

Bench Testing/Performance Testing: To ensure the device meets established engineering and material standards for safety and function.
Material Equivalence: Demonstrating that the materials used are common, well-characterized, and equivalent to those used in the predicate.
Design Equivalence: Showing that the design principles and features are substantially similar to the predicate.
Sterilization and Packaging Equivalence: Ensuring these aspects are comparable to established methods.

Therefore, the "acceptance criteria" are generally compliance with recognized standards and demonstration of equivalence, rather than specific sensitivity/specificity thresholds or clinical outcomes from a human study.

Here's a breakdown of the requested information based on the provided document:

Acceptance Criteria and Study for P.F.C. Sigma Porous Modular Keel Tibial Tray

The "acceptance criteria" and "study" for this device are framed within the context of a 510(k) submission, which aims to demonstrate substantial equivalence to a legally marketed predicate device rather than presenting a de novo clinical study with pre-defined performance thresholds like those seen in diagnostic AI.

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for a 510(k) submission of this nature are not typically expressed as a table of clinical performance metrics (e.g., sensitivity, specificity) but rather as adherence to recognized standards and demonstration of equivalence to existing devices.

Acceptance Criteria Category	Specific Criteria	Reported Device Performance/Evidence Provided
Intended Use	The device is indicated for use in total knee replacements for severe pain and disability due to permanent structural damage (rheumatoid arthritis, osteoarthritis, post-traumatic arthritis, collagen disorders, pseudogout, trauma, failed prior surgical intervention). It must be used only with PMMA bone cement.	The P.F.C. Sigma Porous Modular Keel Tibial Tray is described with this specific Indication for Use statement, which is identical or highly similar to its predicate devices, affirming its intended purpose. The FDA's response explicitly states this letter will allow you to begin marketing your device as described in your 510(k) premarket notification immediately.
Material Equivalence	Materials of construction (titanium alloy, porous coating, UHMWPE plug) must be biologically compatible and functionally equivalent to predicate devices.	Manufactured from titanium alloy (Ti-6Al-4V) with commercially pure titanium porous coating and a UHMWPE plug. These materials are commonly used in knee prostheses and are considered equivalent to those used in the cited predicate devices (e.g., K892394, K961685, K923807, K864671, K961379).
Design Equivalence	Design features (e.g., modularity, keel, porous coating, screw holes for fixation, compatibility with inserts) must be substantially similar in principle to predicate devices, ensuring comparable mechanical function and clinical performance.	The device features a porous modular keel design, four screw holes for additional fixation, a removable UHMWPE plug for stem extension, and compatibility with P.F.C. Modular and P.F.C. Sigma tibial inserts. These design elements are demonstrated to be "substantially equivalent in terms of [...] design" to the predicate devices listed. The reference to "P.F.C. Sigma tibial inserts, including curved posterior lipped and stabilized" further shows design compatibility within the system.
Performance Testing	Device must meet relevant voluntary performance standards (e.g., ASTM standards) for mechanical strength, fatigue, fixation, and other relevant properties to ensure safe and effective performance.	The determination of substantial equivalence was based on "performance testing and conformance with voluntary performance standards. e.g. ASTM F-1580, ASTM F620 and ASTM F1044." This indicates mechanical and material tests were conducted to demonstrate compliance with these established standards for implantable medical devices.
Sterilization & Packaging	Method of sterilization (not explicitly stated but implied to be standard for implants) and packaging must ensure sterility and device integrity until use, comparable to predicate devices.	The summary states the device is "substantially equivalent in terms of [...] sterilization method, and packaging" to the predicate devices, implying these aspects meet established industry and regulatory requirements.
Labeling	Labeling must clearly state indications for use, contraindications, and any specific requirements (e.g., "for cemented use only"). Must comply with general control provisions (annual registration, listing, GMP, misbranding, adulteration).	The FDA letter explicitly mandates: "This device may not be labeled or promoted for non-cemented use." and "All labeling for this device...must prominently state that the device is intended for cemented use only." This demonstrates that the labeling requirements (acceptance criteria) were identified and addressed as a condition of clearance. The general control provisions are also explicitly mentioned in the FDA letter.

2. Sample Size Used for the Test Set and Data Provenance

For a 510(k) submission for a knee prosthesis, especially one demonstrating substantial equivalence through bench testing, there isn't a "test set" in the clinical trial sense with human patients. Instead, the "test set" refers to the number of devices or material samples subjected to the specified performance tests.

Sample Size for Test Set: Not explicitly stated in the provided document. The ASTM standards (F-1580, F620, F1044) cited would specify the minimum number of samples required for each particular test (e.g., fatigue, tensile strength, shear strength).
Data Provenance: The "study" here is primarily bench testing conducted by the manufacturer (DePuy Orthopaedics, Inc.) according to recognized industry standards. This data would be generated in a laboratory setting, likely within the United States (where the manufacturer is based), and is inherently a prospective generation of data for the submission.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

This question is not applicable to this type of 510(k) submission. "Ground truth" established by human experts is typically relevant for diagnostic devices or AI algorithms where the device's output is compared against expert interpretation of medical images or patient conditions. For a knee prosthesis whose clearance is based on substantial equivalence and performance testing to engineering standards, human expert "ground truth" for the test set is not a component of the submission described here.

4. Adjudication Method for the Test Set

Not applicable. As noted above, there isn't a clinical "test set" requiring expert adjudication for this 510(k) submission. The "adjudication" for the performance testing would be the interpretation of the physical test results against the pass/fail criteria defined by the ASTM standards.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study Was Done

No. An MRMC study is a type of clinical study typically used for diagnostic devices (especially imaging-based ones) to compare reader performance with and without AI assistance. This 510(k) submission is for an implantable knee prosthesis, not a diagnostic device, and therefore such a study was not performed or necessary for its clearance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Not applicable. This device is a physical knee prosthesis, not an algorithm or AI system.

7. The Type of Ground Truth Used

The "ground truth" in this context refers to the established scientific and engineering principles and standards that underpin the safety and effectiveness of implantable devices. This includes:

Material properties: Measured values meeting specified ranges (e.g., tensile strength, fatigue life).
Biocompatibility: Demonstrated non-toxicity and long-term acceptance by the body through established testing and material history.
Mechanical performance: Ability to withstand physiological loads and stresses as tested against ASTM or similar standards.
Clinical history of predicate devices: The safety and efficacy of the substantially equivalent predicate devices effectively serve as the "ground truth" for the clinical utility of the device in question.

8. The Sample Size for the Training Set

Not applicable. This device does not involve a "training set" in the context of machine learning or AI.

9. How the Ground Truth for the Training Set Was Established

Not applicable. As there is no training set, this question is not relevant.

In summary: The provided 510(k) summary and FDA clearance letter detail a process of demonstrating substantial equivalence for an implantable medical device. The "acceptance criteria" revolve around meeting established engineering standards and showing comparability to already-cleared predicate devices, rather than clinical performance metrics from a human study. The "study" primarily consists of bench testing, not clinical trials or AI algorithm validation.

Summary

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K991106

510(k) Summary P.F.C. Sigma Porous Modular Keel Tibial Tray

DePuy Orthopaedics, Inc. 700 Orthopaedic Drive Warsaw, IN 46581

A. Contact Person:

Janet G. Johnson, RAC Senior Regulatory Associate (219) 372-7484

B. Device Information:

Proprietary Name:	P.F.C. Sigma Porous Modular Keel Tibial Tray
Common Name:	Tibial Tray
Classification Name:	Knee Joint Patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis
Regulatory Class:	Class II, per 21 §CFR 888.3560
Product Code:	87 JWH

C. Indications for Use:

The P.F.C. Sigma Porous Modular Keel Tibial Tray is indicated for use in total knee The I .. . . Sigma Forde moveing from severe pain and disability due to permanent structural damage in the knew ing from rheumatoid arthritis, osteoarthritis, post-traumatic surthritis, collagen disorders, or pseudogout. This damage may also be the result of trauma or failed prior surgical intervention.

In accordance with Federal (USA) requirements, the P.F.C. Sigma Knee Modular Kccl Tibial Tray is indicated for use only with PMMA bone cement.

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D. Device Description:

The P.F.C. Sigma Porous Modular Keel Tibial Tray is designed for use with both P.F.C. Modular and P.F.C. Sigma tibial inserts, including curved posterior lipped and stabilized.

E. Substantial Equivalence:

The P.F.C. Sigma Porous Modular Keel Tibial Tray is substantially equivalent in terms of intended use, materials, design, sterilization method, and packaging to the P.F.C. Modular Tibial Tray -Porous (K892394 and K961685), P.F.C. Modular Plus Tibial Tray (K923807 and K961685), AMK Total Knee (K864671) and CRX Tibial Tray (K961379).

The determination of substantial equivalence for this device was based on a detailed device description, performance testing and conformance with voluntary performance standards. e.g. ASTM F-1580, ASTM F620 and ASTM F1044.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/2/Picture/2 description: The image shows the seal of the Department of Health & Human Services - USA. The seal is circular and contains the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. In the center of the seal is an abstract symbol that resembles an eagle or bird with stylized wings.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

d 1899 JUN

Janet G. Johnson, RAC Janet G. Johnson, Associate Senior Regardic, Inc. P.O. Box 988 700 Orthopaedic Drive 700 Orthopaedio Bossona 46581-0988
Warsaw, Indiana 46581-0988

K991106
P.F.C. Sigma Porous Modular Keel Tibial Tray
Classes Classes Classe, II Re : Regulatory Class : II Product Code: JHW Dated: March 30, 1999 April 1, 1999 Received:

Dear Ms. Johnson:

Deal nove reviewed your Section 510 (k) notification of intent to we have reviewed your Section 510(K) noce have determined the market the for no market the device referenced above and we indications for
device is substantially equivalent (for the indications for device is substantially equivalent (ib) the enables marketed in interestate
use stated in the May 28, 1976 the enactment date of the use stated in the enclosure) to devices manned date of the commerce prior to May 28, 1978, che chaobment Medical Device Amendents of to devices that work.
reclassified in accordance with the provisions of the based of reclassified in accordance with the provisions of the rood, Drug, and Cosmetic Act (Act). Thirs decises labeled
this device being equivalent only to similar devices labeled and intended to be fixed within bone with acrylic "bone and intended to be fixed within bone were your device subject to cement." You may, therefore, market your act and the following the general control limitations:

This device may not be labeled or promoted for non-1. cemented use.
All labeling for this device, including package label
s and for the led within the package, must 2. All labeling for this action the package, must and labeling included within the promises.
prominently state that the device is intended for cemented use only.

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Page 2 Janet G. Johnson, RAC

3 . Any non-cemented fixation of this device is considered 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 TTT (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 regulation may result in regulatory action. In addition, FDA may publish further announcements 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 Regulations.

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 viter 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 Other general information on your responsibilities under the Act may be

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Page 3 - Janet G. Johnson, RAC

obtained from the Division of Small Manufacturers Assistance obtained from the Division of Small Manufacearch 100 mg 1501 https://www.bac
at its toll-free number (800) 638-2041 or (301) 443-6597 obj. at its toll-free number (800) 638-2041 of (301) 449-697 08-11-2
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 - Reseord Device Evaluation Center for Devices and Radiological Health

Enclosure

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510(k) Number (if known)
Device Name

1991106 P.F.C. Sigma Porous Modular Keel Tibial Tray

Indications for Use

The P.F.C. Sigma Porous Modular Keel Tibial Tray is indicated for use in total knee
r in the many and commend simp from severe pain and disability due to permanent The P.F.C. Sigma Porous Modular Keel Tibal Tray Is Indiano Ior users and replacements of patients suffering from severe pain and only and on on or experientiality
structural danage in the knee as neardorout . This damage may also be the result of structural damage in the knee joint from rheumatoid artist. Shoolarines p
arthritis, collagen disorders, or pseudogout. This damage may also be the result of trauma
nt the r artifits, conagers surgical intervention.

In accordance with Federal (USA) requirements, the P.F.C. Sigma Knee Modular Keel
, In accordance with a more with RMMA bone cement. In accordance with Federal (USA) requirements,
Tibial Tray is indicated for use only with PMMA bone cement.

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Prescription Use_ × (Per 21 CFR §801.109) OR

Over-the-Counter Use_

(Optional Format 1-2-96)

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Division of General Restorative Devices K94104

Regulation Number and Section

§ 888.3560 Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.

(a)
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).(b)
Classification. Class II.