The 3 Channel Knee Electronic Amplified Stethoscope is intended for use by a physician as a noninvasive tool to amplify and record distinct sounds (vibrations) within the three compartments (medial, lateral, and patellar) of the knee joint.

Device Description

The device is intended for use by a physician as a noninvasive tool to amplify and record distinct sounds (vibrations) within the three compartments (medial, lateral, and patellar) of the knee joint.

The 3 Channel Knee Stethoscope System consists of three transducers, or sensors, to pick up the vibrations (sound) from three locations on the knee. The transducers are plugged into an amplifier box that is connected to a standard personal computer installed with Windows 3.1, or later version. A goniometer attachment is also plugged into the amplifier box. The system generates a metronome arrow that moves on the computer monitor screen (3 seconds per flex/extend cycle). The patient watches the arrow to pace the speed and direction of knee flexion and extension, while staying "in sync" with the metronome to maintain a 3 second cycle. Motion and sound vibrations are amplified, recorded in graph form, and stored in a patient database.

AI/ML Overview

Here's an analysis of the provided text regarding the acceptance criteria and study for the 3 Channel Knee Electronic Amplified Stethoscope:

Acceptance Criteria and Study Analysis

Based on the provided documentation, the "acceptance criteria" for the 3 Channel Knee Electronic Amplified Stethoscope are primarily rooted in demonstrating substantial equivalence to existing legally marketed predicate devices. The device is not making claims of diagnostic capability, but rather as an adjunct tool for amplification and recording. Therefore, the "studies" presented are historical and foundational research on the broader concept of "vibration arthrography" rather than a direct, specific study proving the performance of this specific device against defined acceptance criteria.

The submission is a 510(k) for a Class II medical device, which typically relies on demonstrating equivalence rather than extensive clinical efficacy trials.

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria Category	Specific Criteria (Implicit from 510(k))	Reported Device Performance / Supporting Evidence
Intended Use	To amplify and record distinct sounds (vibrations) within the three compartments of the knee joint as a noninvasive physician's tool.	The device description explicitly states this intended use. Claims equivalence to predicate stethoscopes for amplification and recording.
Safety	Minimize risks to the patient.	Stated as minimal risk; not intended for diagnosis, but as an adjunct. No energy applied to the patient.
Functionality	Magnify vibrations (sounds) and make them more discernible. Process, store, and display sound recordings.	Stated as equivalent to 3M Littmann Electronic Stethoscope for amplification and filtering. Equivalent to Transmedica Model 100 Digital Electronic Stethoscope for processing, storing, and displaying sound recordings using multiple piezoelectric transducers and a general purpose digital computer.
Technological Characteristics	Use of transducers, amplifier, computer interface, goniometer, metronome for pacing.	Device description details these components and their function.
Substantial Equivalence	Equivalent in intended use and technological characteristics to legally marketed predicate devices (3M Littmann Electronic Stethoscope, Transmedica Model 100 Digital Electronic Stethoscope).	explicitly affirmed by the FDA in the approval letter (K991756) based on the submitted information. The document extensively compares its functions to these predicates.
Diagnostic Claims	No interpretive or diagnostic capabilities claimed.	Explicitly stated: "There are no interpretive or other diagnostic capabilities currently claimed for this device."

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

The 510(k) submission does not mention a specific test set or sample size used for the performance evaluation of this particular device. The "studies" cited are published papers on the general concept of "vibration arthrography" or electro-acoustical techniques for detecting knee joint noise, dating from 1976 to 1990. These papers are foundational for the field, but not direct performance studies of the Biomet 3 Channel Knee Electronic Amplified Stethoscope itself. Therefore, details like data provenance specific to this device's testing are not provided.

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

This information is not provided as there is no specific test set described for this device's performance evaluation. The cited published papers (e.g., Chu et al., Kernohan et al., McCoy et al., Mollan et al., Wallace et al.) in the "Published Papers" section would have involved experts in their respective studies, but these are not studies of this specific device's performance or a means to establish "ground truth" for its acceptance.

4. Adjudication Method for the Test Set

This information is not provided as there is no specific test set described for this device's performance evaluation.

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

No, an MRMC comparative effectiveness study was not done for this device as described in the provided text. The device is not claiming interpretative or diagnostic capabilities, and the focus of the 510(k) is on substantial equivalence for amplification and recording. There is no mention of human readers improving with or without AI assistance, as the device itself is a purely signal amplification and recording tool, not an AI-driven diagnostic system.

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

The concept of a "standalone" algorithm performance study is not applicable to this device in the way it's usually understood for AI/diagnostic algorithms. The device's primary function is to amplify and record, then display the data for a physician to interpret. It's a "human-in-the-loop" device by its very nature, where the human physician provides the interpretation. There is no algorithm that provides a standalone diagnostic output.

7. The Type of Ground Truth Used

Given the nature of the device (amplification and recording, not diagnosis), the concept of "ground truth" for its performance evaluation is not directly applicable in the sense of pathology, expert consensus on a diagnosis, or outcomes data. The "ground truth" for the device's acceptance is its ability to accurately amplify and record sounds and its substantial equivalence to predicate devices that perform similar functions. The historical research cited (e.g., "The Diagnosis Potential of Vibration Arthography," "Vibration Arthrography as a Diagnostic Aid") suggests that the field uses clinical findings, imaging, or surgical outcomes to correlate with vibration patterns, but this is for interpreting the data from such devices, not for validating the device's basic function of amplification and recording.

8. The Sample Size for the Training Set

This device does not contain a machine learning or AI algorithm in the contemporary sense that would require a "training set." Therefore, this information is not applicable and not provided.

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

As there is no training set for an AI algorithm, this information is not applicable and not provided.

Summary

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DEC 1 0 1999

510(K) Summary

Sponsor.

Biomet, Inc. P.O. Box 587 Airport Industrial Park Warsaw, Indiana 46581

Device.

3 Channel Knee Electronic Amplified Stethoscope (Electronic Stethoscope with Goniometer Attachment)

Classification Name.

Stethoscope, Electronic-Amplified (21 CFR 888.1875) / Goniometer (21 CFR 888.1500)

Device Description.

The device is intended for use by a physician as a noninvasive tool to amplify and record distinct sounds (vibrations) within the three compartments (medial, lateral, and patellar) of the knee joint.

Potential Risks.

A potential risk is the device or its software malfunctions in such a way that it provides inaccurate information to a physician. However, should such a malfunction occur, the risk is minimal to the patient since the device is not intended to a means of diagnosis, but an adjunct to diagnostic tools used by the physician. The device is intended to help the physician to confirm the diagnosis and to identify the location and severity of the injury or disease condition within the knee joint. No energy is applied to the patient by the device.

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Substantial Equivalence.

The purpose of a stethoscope, electronic amplified is to magnify any vibrations (sounds) and make them more discernable to the clinician. The 3 Channel Knee Electronic Amplified Stethoscope is equivalent to 3M Littimann Electronic Stethoscope based upon its intended use for the amplification of faint heart, lungs, and other body sounds as well as normal auscultation and selective frequency filtering. In addition, it is substantially equivalent to the Transmedica Model 100 Digital Electronic Stethoscope in that it uses multiple piezzo-electric transducers and a general purpose digital computer to process, store, and display the sound recordings. Please note that stethoscopes are a listening tool for the physician, and have been used historically to amplify a wide variety of soundswithin the human body, including human joints.

The 3 Channel Knee Electronic Amplified Stethoscope helps the physician to better visualize the location of the vibration. There are no interpretive or other diagnostic capabilities currently claimed for this device. However we intend to initiate further testing to determine if interpretive capability is possible.

Published Papers

1. ML Chu, IA Gradisar, MR Railey, and GF Bowling (1976); An Electro-Acoustical Technique for the Detection of Knee Joint Noise, Medical Research Engineering, Vol.12, No.1, 18-20.
1. WG Kernohan, DE Beverland, GF McCov, SN Shaw, RGH Wallace, GC McCullagh, RAB Mollan (1986); The Diagnosis Potential of Vibration Arthography. Clinical Orthopaedics and Related Research, Number 210, September: 106-12.
1. WG Kernohan, DE Beverland, GF McCoy, A Hamilton, P Watson, R Mollan (1990); Vibration Arthrometry. Acta Orthop Scand, 61(1):70-79.
1. GF McCoy, JD McCrea, DE Beverland, WG Kernohan, RAB Mollan (1987); Vibration Arthrography as a Diagnostic Aid in Diseases of the Knee. The Journal of Bone and Joint Surgery, Vol.69B, No.2, March, 288-93.
1. RAB Mollan, GW Kernohan, and PH Watters (1983): Artefact Encountered by the Vibration. Journal of Biomechanics, 16(3): 193-9.
1. RGH Wallace, RAB Mollan, WG Kernohan; Preliminary report on a New Technique to Aid Diagnosis of Some Disorders Found in Hands. (1985); The Journal of Hand Surgery, Vol. 10B, No.2: June: 269-72.

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Public Health Service

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DEC 1 0 1999

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Ms. Lonnie Witham Senior Requlatory Affairs Specialist Biomet Inc. P.O. Box 587 Warsaw, IN 46581-0587

Re: K991756 3 Channel Knee Electronic Amplified Stethoscope Regulatory Class: II (two) Product Code: DOD September 15, 1999 Dated: Received: September 16, 1999

Dear Ms. Witham:

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 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). 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 (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 requirements, 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.

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Page 2 - Ms. Lonnie Witham

This letter will allow you to begin marketing your device as described in your 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 and additionally 809.10 for in vitro diaqnostic devices), please contact the Office of Compliance at (301) 594-4648. 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" (21CFR 807.97). Other general information on your responsibilities under the Act may be 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/dsma/dsmamain.html".

Sincerely yours,

sincerely, yours,

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

Enclosure

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STATEMENT OF INDICATIONS FOR USE

510(K) NUMBER K991756

DEVICE NAME: 3 CHANNEL KNEE ELECTRONIC AMPLIFIED STETHOSCOPE

INDICATIONS FOR USE:

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use (Per 21 CFR 801.109 OR

Over-The-Counter-Use (Optional Format 1-2-96)

VQa Vn Tth

diovascular. Respiratory,

000002

Regulation Number and Section

§ 870.1875 Stethoscope.

(a)
Manual stethoscope —(1)Identification. A manual stethoscope is a mechanical device used to project the sounds associated with the heart, arteries, and veins and other internal organs.(2)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.(b)
Electronic stethoscope —(1)Identification. An electronic stethoscope is an electrically amplified device used to project the sounds associated with the heart, arteries, and veins and other internal organs.(2)
Classification. Class II (special controls). The device, when it is a lung sound monitor, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.