The TriGen Hindfoot Fusion Nail (HFN) is indicated for degeneration, deformity, or trauma of both the tibiotalar and talocalcaneal articulations in the hindfoot; tibiocalcaneal arthrodesis; combined arthrodesis of the ankle and sub-talar joints; avascular necrosis of the ankle and sub-talar joints; failed total ankle replacement with sub-talar intrusion; failed ankle arthrodesis with insufficient talar body; rheumatoid arthritis; severe deformity secondary to untreated talipes equinovarus or neuromuscular disease; and severe pilon fractures with trauma to the subtalar joints. The TriGen HFN is for single use only.

Device Description

The TriGen Hindfoot Fusion Nail (HFN) is an intramedullary nail used for fixation of the ankle and hind foot. The TriGen HFN nails are made from titanium alloy conforming to ASTM F 1472 and are used with existing bone screws.

AI/ML Overview

This document is a 510(k) premarket notification for a medical device called the "TriGen Hindfoot Fusion Nail." This type of submission is for demonstrating "substantial equivalence" to a predicate device, not for proving effectiveness through comprehensive clinical studies with acceptance criteria in the way a PMA (Premarket Approval) submission would.

Therefore, much of the requested information regarding acceptance criteria, specific study design details, ground truth establishment, sample sizes for training/test sets, expert involvement, and comparative performance metrics (like MRMC studies or standalone algorithm performance) is not applicable or available in this type of regulatory document.

Here's a breakdown based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Mechanical Equivalence to Predicate Devices	"A review of the mechanical test data indicated that the TriGen HFN is equivalent to devices currently used clinically and is capable of withstanding expected in vivo loading without failure."
Substantial Equivalence (Overall Regulatory)	The FDA determined the device is "substantially equivalent...to legally marketed predicate devices" based on similarities in indications for use, design features, operational principles, and material composition.

2. Sample size used for the test set and the data provenance

Not Applicable. This submission relies on demonstrating substantial equivalence to predicate devices and mechanical testing, not a clinical study on a "test set" of patients with specific outcomes.
The "test set" here refers to the mechanical tests conducted. No sample size for a patient test set is mentioned.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

Not Applicable. There is no mention of "ground truth" establishment by experts in the context of a patient test set for performance evaluation. The "ground truth" for substantial equivalence is based on the characteristics of the predicate devices.

4. Adjudication method for the test set

Not Applicable. No clinical trial or patient test set requiring adjudication is described.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not Applicable. This is a physical orthopedic implant; AI assistance for readers is not relevant.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not Applicable. This is a physical orthopedic implant; there is no "algorithm only" performance to evaluate.

7. The type of ground truth used

For regulatory substantial equivalence: The "ground truth" is established by the safety and effectiveness profile of the predicate devices (Smith & Nephew, Inc. Tibia-Talus-Calcaneus Nail K950394 and Encore Orthopedics UltiMax Ankle Fusion Rod System K991790). The new device is compared against these already-marketed devices.
For mechanical testing: The "ground truth" for mechanical integrity is likely derived from established engineering standards and performance of reference devices under simulated physiological loading conditions.

8. The sample size for the training set

Not Applicable. There is no "training set" in the context of device performance in this type of submission. If "training set" refers to data used to design or refine the device, that is not explicitly detailed here.

9. How the ground truth for the training set was established

Not Applicable. (See #8)

Summary

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K043052

NOV 2 4 2004

Smith & Nephew, Inc. Summary of Safety and Effectiveness TriGen Hindfoot Fusion Nail

Date of Summary: November 4, 2004

Contact Person and Address

Janet Johnson Akil Director, Regulatory Affairs Smith & Nephew, Inc. Orthopaedic Division 1450 Brooks Road Memphis, TN 38116 1901) 399-5153

Name of Device: TriGen Hindfoot Fusion Nail Common Name: Intramedullary Fixation Rod

Device Description

Device Classification

21 CFR 888.3020 Intramedullary fixation rod - Class II

Mechanical and Clinical Data

A review of the mechanical test data indicated that the TriGen HFN is equivalent to devices currently used clinically and is capable of withstanding expected in vivo loading without failure.

Indications for Use

Substantial Equivalence Information

The substantial equivalence of the TriGen HFN is based on its similarities in indications for use, design features, operational principles, and material composition to the following predicate devices - the Smith & Nephew, Inc. Tibia-Talus-Calcaneus Nail (K950394) and the Encore Orthopedics UltiMax Ankle Fusion Rod System (K991790).

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Image /page/1/Picture/1 description: The image shows the logo for the Department of Health & Human Services - USA. The logo consists of a circle with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" around the perimeter. Inside the circle is an abstract image of an eagle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

NOV 2 4 2004

Ms. Janet Johnson Akil Director, Regulatory Affairs Smith & Nephew, Inc. Orthopaedic Division 1450 Brooks Road Memphis, Tennessee 38116

Re: K043052

Trade/Device Name: TriGen Hindfoot Fusion Nail Regulation Number: 21 CFR 888.3020 Regulation Name: Intramedullary fixation rod Regulatory Class: II Product Code: HSB Dated: October 4, 2004 Received: October 5, 2004

Dear Ms. Akil:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), 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 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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Page 2 - Ms. Janet Johnson Akil

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (240) 276-0120. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely yours,

Mark A. Milburn

Celia M. Witten, Ph.D., M.D. Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known):

Device Name: TriGen Hindfoot Fusion Nail

Indications for Use:

The TriGen Hindfoot Fusion Nail (HFN) is indicated for degeneration, deformity, or rauma of both The Tricen Hindbot rusion Nak (11), is marbated for asso ;
the tibiotalar and talocalcaneal articulations in the hindfoot; tibiocalcaneal arthrodest combined the tiblotalial and sub-talarons in the hillering in the nike and sub-talar joints;
arthrodesis of the ankle and sub-talar joints; avascular necrosis of the anily incriff ris annrodesis of the ankle and sub-talar intrusion; failed ankle arthrodesis with insufficient lalled lotal anke replacentern with secondary to untreated talipes equinovarus or lalar body; medihatolu annitis; corors aufemily so the subtalar joints. The TriGen HFN is for single use only.

Prescription Use (Part 21 CFR 801 Subpart D)	X
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AND/OR

Over-The-Counter Use (21 CFR 807 Subpart C)
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(Please do not WRITE BELOW THIS LINE – CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Confurrence of CORH,

510(k) Number K043052

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Regulation Number and Section

§ 888.3020 Intramedullary fixation rod.

(a)
Identification. An intramedullary fixation rod is a device intended to be implanted that consists of a rod made of alloys such as cobalt-chromium-molybdenum and stainless steel. It is inserted into the medullary (bone marrow) canal of long bones for the fixation of fractures.(b)
Classification. Class II.