The Hoffmann® II Micro" External Fixation System is intended for use to provide stabilization of open and/or unstable fractures in children and adults where soft tissue injury precludes the use of other fracture treatments such as IM rodding or other means of internal fixation and for use in reconstruction procedures in conjunction with commercially available Fixation Pins and/or Kirschner Wires. Specific indications include, but are not limited to:

Bone fracture fixation .
. Ostcotomy
. Arthrodesis
Correction of deformity .
Revision procedure where other treatments or devices have been unsuccessful .
Non-unions and delayed unions .
Compression/distraction and lengthening t

Device Description

This line extension is to add new components to the Hoffmann ® II Micro " External Fixation System. This component is an external fixation frame component and can be used with the components in other Howmedica Osteonics' external fixation systems such as the Hoffmann® II Micro" External Fixation System, Hoffmann® II External Fixation System, Hoffmann® II Compact™ External Fixation System, Hoffmann® II Hybrid Frame System, Monotube Triax™ External Fixation System.

AI/ML Overview

Here's an analysis of the provided 510(k) notification for the Hoffmann® II Micro™ External Fixation System Line Extension, focusing on acceptance criteria and study details.

Important Note: The provided document is a 510(k) Summary and the FDA's clearance letter. It states that equivalence is based on "mechanical performance demonstrating substantial equivalence to the predicate devices." This type of submission relies on demonstrating that the new device is as safe and effective as a legally marketed predicate device, often through bench testing and, in this case, direct comparison of materials and design. It is not a clinical study with human patients that aims to prove a certain performance metric (like accuracy for an AI device) against acceptance criteria. Therefore, many of the questions regarding clinical study design (sample size, experts, ground truth, MRMC, standalone performance) are not applicable to this type of device and submission.

Acceptance Criteria and Device Performance (Based on Substantial Equivalence)

Acceptance Criteria (Implied)	Reported Device Performance
Mechanical Performance: Exhibit similar or superior mechanical strength, durability, and functionality as the predicate devices for stabilization of fractures and reconstruction procedures. This would typically involve:	The 510(k) states: "Equivalency is based on similarities in intended use, materials and design to the predicate devices and the mechanical performance demonstrating substantial equivalence to the predicate devices." This implies that bench testing was performed to compare the mechanical properties (e.g., bending strength, torsional rigidity, fatigue life) of the new components against those of the predicate devices, and that the new components met or exceeded the performance of the predicate. Specific numerical performance data or acceptance thresholds are not provided in this summary.
Material Equivalence: Use biocompatible materials with similar or identical properties to the predicate devices.	The 510(k) states: "Equivalency is based on similarities in intended use, materials and design to the predicate devices..." This suggests that the materials used in the new components are either the same as, or have been demonstrated to be equivalent to, those used in the predicate devices.
Design Equivalence: Incorporate design features that are consistent with the predicate devices and existing Hoffmann® II systems, ensuring compatibility and functionality.	The 510(k) states: "Equivalency is based on similarities in intended use, materials and design to the predicate devices..." This indicates that the design of the new components is consistent with the established external fixation system, allowing for proper assembly and function with other components.
Intended Use Equivalence: Operate within the same indications for use as the predicate devices.	The "Intended Use" section clearly aligns with the existing Hoffmann® II Micro™ External Fixation System, serving to stabilize fractures and assist in reconstruction procedures. The clearance letter confirms the FDA's acceptance of these indications for use as substantially equivalent to the predicate.

Study Details (Applicable to 510(k) Substantial Equivalence, Not a Clinical AI Study)

Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not applicable. This was a 510(k) submission based on substantial equivalence, which primarily relies on comparing the new device to a predicate through bench testing (mechanical performance) and design/material analysis, rather than a "test set" of clinical data. If mechanical testing was performed, the "sample size" would refer to the number of devices or components tested. This number is not provided in the summary.
- Data Provenance: Not applicable in the context of clinical data. For mechanical testing, the data would be generated in a lab setting, likely in the US (where the company is based). The data would be prospective in the sense that the tests are conducted specifically for the submission.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. There was no clinical "test set" requiring expert-established ground truth for this type of submission. Mechanical testing relies on engineering standards and measurements, not expert clinical consensus.
Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable. There was no clinical "test set" requiring adjudication.
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:
- No. This is an external fixation system (a physical medical device), not an AI diagnostic tool. MRMC studies are not relevant here.
If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- No. This is a physical medical device. The concept of "standalone algorithm performance" is not applicable.
The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- Not applicable in the clinical sense. For mechanical testing, the "ground truth" would be established engineering standards, material properties, and objective measurements (e.g., force, displacement, cycles to failure).
The sample size for the training set:
- Not applicable. This is not an AI/machine learning device.
How the ground truth for the training set was established:
- Not applicable. This is not an AI/machine learning device.

Summary:

The Hoffmann® II Micro™ External Fixation System Line Extension received 510(k) clearance based on demonstrating substantial equivalence to existing predicate devices. This type of submission relies on showing that the new device has the same intended use, is made of similar materials, has a similar design, and exhibits comparable or superior mechanical performance to devices already on the market. The provided documentation does not detail a clinical study with human subjects, nor does it involve AI or software performance metrics that would require intricate ground truth establishment, expert adjudication, or MRMC studies. The "study" proving acceptance criteria was likely a series of bench tests comparing the new components' mechanical properties to those of the predicate devices.

Summary

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Hoffmann® II Micro Line Extension

MAR 4 - 2005

iC050048

510(k) Premarket Notification

510(k) Summary of Safety and Effectiveness for the Hoffmann® II Micro™ External Fixation System Line Extension

Proprietary Name:	Hoffmann® II MicroTM External Fixation System
Common Name:	External Fixation Frame Components
Classification Name and Reference	Single/multiple component metallic bone fixationappliances and accessories, 21 CFR §888.3030 andSmooth or threaded metallic bone fixation fastener,21 CFR §888.3040
Device Product Code:	87 KTT, 87 LXT & 87 JEC
For Information contact:	Vivian Kelly, Regulatory Affairs SpecialistHowmedica Osteonics Corp.325 Corporate DriveMahwah, NJ 07430Phone: (201) 831-5581Fax: (201) 831-6038
Date Summary Prepared:	January 7, 2004

Intended Use:

Description:

Substantial Equivalence:

Equivalency is based on similarities in intended use, materials and design to the predicate devices and the mechanical performance demonstrating substantial equivalence to the predicate devices.

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DEPARTMENT OF HEALTH & HUMAN SERVICES

Image /page/1/Picture/1 description: The image shows the logo for the U.S. Department of Health & 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, symbolizing the department's mission to protect the health of all Americans.

Public Health Service

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

MAR 4 - 2005

Ms. Vivian Kelly Regulatory Affairs Specialist Howmedica Osteonics Corp. 325 Corporate Drive Mahwah, New Jersey 07430

Re: K050048 Trade/Device Name: Hoffmann® II Micro™ External Fixation System Regulation Numbers: 21 CFR 888.3030 Regulation Name: Single/multiple component metallic bone fixation appliances and accessories Regulatory Class: II Product Codes: KTT Dated: January 7, 2005 Received: January 10, 2005

Dear Ms. Kelly:

We have reviewed your Section 510(k) premarket notification of intent to market the device wt nave teviewed your bection of the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate for use stated in the encreased of the enactment date of the Medical Device Amendments, or to conimeres phor to may 20, 1978) in accordance with the provisions of the Federal Food, Drug, devices that have been resuire approval of a premarket approval application (PMA). and Costletter Fer (110) and the device, subject to the general controls provisions of the Act. The I va may, merelore, maniev 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 If your device is blussined too works. Existing major regulations affecting your device can may be subject to back as a submitions, 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 r rease be actived that the revilation that your device complies with other requirements of the Act that 1 DA has intact a and regulations administered by other Federal agencies. You must of any I edetar statuates and equirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set Of It i att 607), laooning (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. Vivian Kelly

This letter will allow you to begin marketing your device as described in your Section 510(k) This letter will anow you to oegin manteang your as a couvalence of your device to a legally premarket noticate 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 If you ucate specific advice in 10-2 10-0120. Also, please note the regulation entitled, contact the Office of Comphane as (21 ) in the motification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small other general informational 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/industry/support/index.html.

Sincerely yours,

Mark A. Millhiser

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: Hoffmann® II Micro™ External Fixation System

Indications for Use:

The Hoffmann® II Micro™ External Fixation System is intended for use to provide stabilization of open and/or unstable fractures in children and adults where soft tissue injury precludes the use of other fracture treatments such as IM rodding or casting or other means of internal fixation and for use in reconstruction procedures in conjunction with commercially available Fixation Pins and/or Kirschner Wires. Specific indications include, but are not limited to:

Bone fracture fixation .
. Ostcotomy
. Arthrodesis
Correction of deformity .
Revision procedure where other treatments or devices have been unsuccessful .
Non-unions and delayed unions .
Compression/distraction and lengthening t

Over-The-Counter Use Prescription Use X AND/OR (21 CFR 807 Subpart C) (Part 21 CFR 801 Subpart D) (PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of General, Restorative,
and Neurological Devices

S10(k) Number: K050048

Page 1 of 1

Regulation Number and Section

§ 888.3030 Single/multiple component metallic bone fixation appliances and accessories.

(a)
Identification. Single/multiple component metallic bone fixation appliances and accessories are devices intended to be implanted consisting of one or more metallic components and their metallic fasteners. The devices contain a plate, a nail/plate combination, or a blade/plate combination that are made of alloys, such as cobalt-chromium-molybdenum, stainless steel, and titanium, that are intended to be held in position with fasteners, such as screws and nails, or bolts, nuts, and washers. These devices are used for fixation of fractures of the proximal or distal end of long bones, such as intracapsular, intertrochanteric, intercervical, supracondylar, or condylar fractures of the femur; for fusion of a joint; or for surgical procedures that involve cutting a bone. The devices may be implanted or attached through the skin so that a pulling force (traction) may be applied to the skeletal system.(b)
Classification. Class II.