K991756 · Bio-Research Associates, Inc. · DQD · Dec 10, 1999 · Cardiovascular
Device Facts
Record ID
K991756
Device Name
3 CHANNEL KNEE ELECTRONIC AMPLIFIED STETHOSCOPE
Applicant
Bio-Research Associates, Inc.
Product Code
DQD · Cardiovascular
Decision Date
Dec 10, 1999
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 870.1875
Device Class
Class 2
Indications for Use
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 Story
Device captures acoustic vibrations from three knee compartments (medial, lateral, patellar) using three piezoelectric transducers. Signals are processed via an amplifier box connected to a PC. System includes a goniometer attachment to track knee flexion/extension; generates a visual metronome on-screen to guide patient movement at a 3-second cycle. Data is amplified, recorded as graphs, and stored in a database. Used in clinical settings by physicians as an adjunct diagnostic tool to confirm clinical findings. Provides visual/auditory data to assist clinicians in identifying location and severity of joint pathology. No energy is applied to the patient.
Clinical Evidence
No clinical data provided. Device relies on historical clinical literature regarding vibration arthrography as a diagnostic aid for knee disorders.
Technological Characteristics
System utilizes three piezoelectric transducers for vibration sensing. Includes a goniometer for motion tracking. Connects to a standard PC via an amplifier box. Software runs on Windows 3.1 or later. No energy is applied to the patient. Non-invasive, passive sensing.
Indications for Use
Indicated for use by physicians as a noninvasive tool to amplify and record knee joint vibrations (medial, lateral, and patellar compartments) to assist in identifying injury or disease location and severity. Prescription use only.
Regulatory Classification
Identification
Manual stethoscope: A mechanical device used to project the sounds associated with the heart, arteries, and veins and other internal organs. Electronic stethoscope: An electrically amplified device used to project the sounds associated with the heart, arteries, and veins and other internal organs.
Special Controls
*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.
Predicate Devices
3M Littmann Electronic Stethoscope
Transmedica Model 100 Digital Electronic Stethoscope
Submission Summary (Full Text)
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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.
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.
#### 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.
- 2. 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.
- 3. WG Kernohan, DE Beverland, GF McCoy, A Hamilton, P Watson, R Mollan (1990); Vibration Arthrometry. Acta Orthop Scand, 61(1):70-79.
- 4. 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.
- 5. RAB Mollan, GW Kernohan, and PH Watters (1983): Artefact Encountered by the Vibration. Journal of Biomechanics, 16(3): 193-9.
- 6. 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
Image /page/2/Picture/2 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 emblem featuring three abstract, wave-like shapes that resemble human profiles or birds in flight. The logo is presented in black and white.
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
{4}------------------------------------------------
## STATEMENT OF INDICATIONS FOR USE
510(K) NUMBER K991756
# DEVICE NAME: 3 CHANNEL KNEE ELECTRONIC AMPLIFIED STETHOSCOPE
#### INDICATIONS FOR USE:
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.
### (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)
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diovascular. Respiratory,
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