The KneeAlign™ System with Reference Sensor is a computer controlled system intended to assist the surgeon in determining reference alignment axes in relation to anatomical structures during stereotactic orthopedic surgical procedures. The KneeAlign™ System with Reference Sensor facilitates the accurate positioning of implants and instrumentation, relative to these alignment axes. Example orthopedic surgical procedures include but are not limited to: Total Knee Arthroplasty.

Device Description

The KneeAlign System with Reference Sensor is an innovative non-invasive computer assisted surgical navigation system for use in knee arthroplasty procedures. The KneeAlign System is configured to detect, measure, and display angular measurement changes in a triaxial format. The KneeAlign System with Reference Sensor utilizes a palm-sized computer module and reference sensor to generate positional information in orthopedic procedures providing a sequence of steps for registration of anatomical landmarks, calculation of mechanical axes, and positioning of instruments relative to the mechanical axes. In knee arthroplasty procedures, the device assists the surgeon in establishing the mechanical axis of the tibia, determining the varus/valgus angle and the posterior slope angle of the cutting block relative to tibia. The KneeAlign System with Reference Sensor comprises a single use computer module and reusable instrumentation. The KneeAlign™ System with Reference Sensor comprises a single use computer module, a reusable reference sensor, and reusable tibial jig. The device utilizes algorithms to convert sensor outputs into spatial coordinates, providing graphical representation of instruments and anatomy on the user display screen.

AI/ML Overview

The provided 510(k) summary for the KneeAlign™ System indicates that its acceptance criteria and the study proving it meets these criteria are primarily based on demonstrating substantial equivalence to predicate devices through various performance tests. However, the document does not explicitly state specific numerical acceptance criteria for accuracy or performance metrics, nor does it provide a direct table of acceptance criteria versus reported device performance.

Instead, the submission focuses on a comparative approach, asserting that if the device performs comparably to the legally marketed predicate devices, it is considered safe and effective.

Here's a breakdown of the information available and what is not explicitly stated:

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria (Implied)	Reported Device Performance (Implied)
Functional Equivalence: Device performs its intended function (measuring and displaying angular changes/positional information for total knee arthroplasty)	"Simulated use testing confirms that the KneeAlign System with Reference Sensor can be used according to its intended use." The system is "configured to detect, measure, and display angular measurement changes in a triaxial format." It assists in "establishing the mechanical axis of the tibia, determining the varus/valgus angle and the posterior slope angle of the cutting block relative to tibia."
Accuracy: Device provides accurate positional information and alignment axes.	"System accuracy testing" was performed. The device "facilitates the accurate positioning of implants and instrumentation." While specifics are not provided, the claim of substantial equivalence implies that its accuracy is comparable to predicate devices.
Safety: Device is safe for its intended use, without posing undue risks to patients or users.	"Safety and performance...validated to insure it meets its intended use." This included: Bench Testing (system accuracy, performance, laser), Software Validation, Cleaning and Sterilization Validation, Biocompatibility Assessment, Electrical Safety and Electromagnetic Compatibility Testing (IEC 60601-1, IEC 60601-1-2), and Simulated Use/Cadaver Testing.
Substantial Equivalence: Device is as safe and effective as predicate devices.	"This testing regime demonstrates that the subject device is substantially equivalent to the legally marketed predicate devices, for its intended use." "The information provided by OrthAlign in this 510(k) application was found to be substantially equivalent to predicate devices..." "A technological comparison and bench, and cadaver testing demonstrate the substantial equivalence of the KneeAlign System with Reference Sensor to the predicate devices."
Compliance with Standards: Device meets relevant medical device standards.	Electrical Safety and Electromagnetic Compatibility Testing against "Safety Requirements for Medical Electrical Equipment (IEC 60601-1)" and "Electromagnetic Compatibility (EMC) Requirements (IEC 60601-1-2)."

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

Sample Size: Not explicitly stated. The document mentions "Simulated Use/Cadaver Testing," implying a test set was used, but the number of cadavers or simulated scenarios is not provided.
Data Provenance: Not explicitly stated. The document doesn't mention the country of origin or whether the data was retrospective or prospective. Given it involves cadaver testing, it would be prospective data collection for the study itself.

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

This information is not provided in the document. Ground truth for cadaver studies typically involves direct measurement by a clinician or engineer, potentially verified by multiple individuals, but no details are given here.

4. Adjudication Method for the Test Set

This information is not provided in the document.

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

No, a MRMC comparative effectiveness study was not done as described (human readers improving with AI vs. without AI assistance). This device is a surgical navigation system, not an AI diagnostic tool primarily evaluated by human readers interpreting images. Its "assistance" is for the surgeon during the procedure, not a post-hoc diagnostic interpretation by multiple readers.
The comparison focuses on the device's performance against predicate devices and the standard of care (visual observation and tactile feedback or existing computer-assisted surgery devices), rather than quantifying human reader improvement with or without the device in an MRMC study setup.

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

Yes, implicitly. The "System accuracy testing" and other bench tests would constitute standalone performance evaluations of the device's algorithms and hardware without a human actively operating it in a surgical scenario. The "Simulated Use/Cadaver Testing" would then involve a human-in-the-loop, but the initial accuracy tests would be standalone.

7. The Type of Ground Truth Used

For "System accuracy testing" and "Simulated Use/Cadaver Testing," the ground truth would likely be established through direct, precise measurements using highly accurate instruments (e.g., optical trackers, mechanical goniometers, or other measurement tools) independent of the device being tested. In cadaver studies, this often involves disarticulation and direct measurement of bone axes or angles after the device's measurements are recorded.
The document does not explicitly state the methodology for establishing this ground truth.

8. The Sample Size for the Training Set

This device is a rule-based or sensor-based system that applies algorithms to convert sensor outputs into spatial coordinates. This is generally not a machine learning/AI system that requires a "training set" in the common sense of supervised learning. Therefore, a training set in the context of machine learning is not applicable or discussed. The algorithms are likely pre-programmed and validated, not trained on a large dataset.

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

As noted above, a training set (in the machine learning sense) is not applicable here as the device operates on established biomechanical principles and sensor data processing rather than learning from data. The accuracy of the underlying algorithms would be validated through engineering principles and possibly through bench testing with known inputs and expected outputs.

Summary

{0}------------------------------------------------

510(K) SUMMARY

11 093998

This 510(k) summary is being submitted in accordance with the requirements of SMDA 1990 and 21 CFR 807.92(c).

Applicant	OrthAlign, Inc.6 CromwellSuite 102Irvine, CA 92618Tel: (949) 715-2424Fax: (866) 204-9844	MAR 2 2 2010
OfficialCorrespondent	Amy WaltersAWE, Inc.338 Vista MaderaNewport Beach, CA 92660amy@orth-align.comTel: (949) 923-9400Fax: (866) 204-9844
Trade Name	KneeAlignTM System with Reference Sensor
Common Name	Stereotaxic Instrument
DeviceClassification	Class II, 21 CFR §882.4560
Product Codes	OLO: Orthopedic Stereotaxic Instrument
Predicate devices	KneeAlign System (K091411)BrainLAB Knee Essential (K073615)TOTAL KNEE SURGETICS Navigation System(K060282)

Substantially Equivalent To:

The KneeAlign™ System with Reference Sensor is substantially equivalent to the previously cleared KneeAlign System (K091411), BrainLAB Knee Essential(K073615), and TOTAL KNEE SURGETICS Navigation System (K060282).

Description of the Device Subject to Premarket Notification:

{1}------------------------------------------------

The current standard of care for knee arthroplasty procedures has the physician estimating these changes either by visual observation and tactile feedback or with assistance of computer assisted surgery devices. The KneeAlign System with Reference Sensor utilizes a palm-sized computer module and reference sensor to generate positional information in orthopedic procedures providing a sequence of steps for registration of anatomical landmarks, calculation of mechanical axes, and positioning of instruments relative to the mechanical axes. In knee arthroplasty procedures, the device assists the surgeon in establishing the mechanical axis of the tibia, determining the varus/valgus angle and the posterior slope angle of the cutting block relative to tibia. The KneeAlign System with Reference Sensor comprises a single use computer module and reusable instrumentation.

Indications for Use:

The KneeAlign System with Reference Sensor has the same indications for use as the previously cleared KneeAlign System (K091411).

The KneeAlign System with Reference Sensor is a computer controlled system intended to assist the surgeon in determining reference alignment axes in relation to anatomical structures during stereotactic orthopedic surgical procedures. The KneeAlignSystem with Reference Sensor facilitates the accurate positioning of implants and instrumentation, relative to these alignment axes.

Example orthopedic surgical procedures include but are not limited to:

Total Knee Arthroplasty/tibial resection .

Technical Characteristics:

The KneeAlign™ System with Reference Sensor comprises a single use computer module, a reusable reference sensor, and reusable tibial jig. The device utilizes algorithms to convert sensor outputs into spatial coordinates, providing graphical representation of instruments and anatomy on the user display screen. .

Performance Data:

Simulated use testing confirms that the KneeAlign System with Reference Sensor can be used according to its intended use. The KneeAlign System with Reference Sensor has been verified and validated according to OrthAlign's procedures for product design and development. The safety and performance of the KneeAlign System with Reference Sensor has been validated to insure it meets its intended use, including:

Bench Testing: System accuracy testing, performance testing, laser . testing
. Software Validation
l Cleaning and Sterilization Validation
I Biocompatibility Assessment
. Electrical Safety and Electromagnetic Compatibility Testing
- . Safety Requirements for Medical Electrical Equipment (IEC

{2}------------------------------------------------

60601-1)

. Electromagnetic Compatibility (EMC) Requirements (IEC 60601-1-2), and
Simulated Use/Cadaver Testing ■

This testing regime demonstrates that the subject device is substantially equivalent to the legally marketed predicate devices, for its intended use.

The information provided by OrthAlign in this 510(k) application was found to be substantially equivalent to predicate devices such as the KneeAlign System (K091411), BrainLAB Knee Essential (K073615) and the TOTAL KNEE SURGETICS Navigation System (K060282).

Basis for Determination of Substantial Equivalence:

A technological comparison and bench, and cadaver testing demonstrate the substantial equivalence of the KneeAlign System with Reference Sensor to the predicate devices.

{3}------------------------------------------------

Image /page/3/Picture/1 description: The image shows the logo for the Department of Health & Human Services (HHS). The logo features the department's name in a circular arrangement around the perimeter. In the center is a stylized emblem consisting of three human profiles facing right, overlaid and connected, representing the department's focus on people and health.

Food and Drug Administration 10903 New Hampshire Avenue Document Control Room W-O66-0609 Silver Spring, MD 20993-0002

MAR 2 2 2010

OrthAlign, Inc. % AWE, Inc. Ms. Amy Walters 338 Vista Madera Newport Beach, California 92660

Re: K093998

Trade/Device Name: KneeAlign™ System with Reference Sensor Regulation Number: 21 CFR 882.4560 Regulation Name: Stereotaxic instrument Regulatory Class: Class II Product Code: OLO Dated: March 01, 2010 Received: March 03, 2010

Dear Ms. Walters:

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 Foond, Or ve 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. Please note: CDRH does not evaluate information related to contract lindility warranties. We remind you; however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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

{4}------------------------------------------------

Page 2 - Ms. Amy Walters

CFR Part 807); labeling (21 CFR Part 801); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); 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.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

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) 796-7100 or at its Internet address http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours.

Radiological Health

Mark N. Melkerson
Director
Division of Surgical, Orthopedic
And Restorative Devices
Office of Device Evaluation
Center for Devices and

Enclosure

{5}------------------------------------------------

INDICATIONS FOR USE STATEMENT

510(k) Number (if known): K093998

Device Name: KneeAlign™ System with Reference Sensor

Indications for Use:

Total Knee Arthroplasty .
Prescription Use X (Part 21 CFR 801 Subpart D)

AND/OR

Over-The-Counter Use (21 CFR 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Mireal formkn

Page / of

(Division Sign-Off Division of Surgical, Orthopedic, and Restorative Devices

510(k) Number K093998

Regulation Number and Section

§ 882.4560 Stereotaxic instrument.

(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).