Muscle Trainer is a product that adopts modern electronic science and technology to delivers electric pulses generated to the user's skin through the electrodes.

Muscle Trainer is mainly composed of the host and electrode patches, as well as it is powered by CR2023 battery. Of which, the electrode patch is cleared in K171381.

Muscle Trainer includes KTR-230 series (KTR-230B, KTR-230W, KTR-230P), KTR-231, KTR-232, KTR-233 and KTR-234 model. All models have three operation modes and one channel, which can give certain electrical pulse through electrode patches on the skin. Their technical parameters are slightly different, but they share the basically same characteristics:

Electric pulse combination, 0~12 levels can be adjusted and chosen according to personal preference.
CR2032 Button batteries (DC3V) power supply, easy to use and safe.

The main differences among them are the followings but not affect its intended use:

Appearance
The number of control button: KTR-230 series, KTR-231 and KTR-232 have two buttons to control: KTR-233 and KTR-234 have three buttons to control.
The number of electrode patch used: KTR-230 series, KTR-233 and KTR-234 are equipped with one electrode patch; KTR-231 is equipped with six electrode patches as well as KTR-232 is equipped with two electrode patches.
Applied parts: KTR-230 series, KTR-233 and KTR-234 apply to abdomen, shoulder, arm, thigh and calf; KTR-231 applies to abdomen in the place where between ribs and hip bones; KTR-232 applies to waist, shoulder, arm, thigh and calf.

AI/ML Overview

The provided text does not contain a typical "acceptance criteria" table with reported device performance metrics in the way one might expect for an AI/ML medical device, as this is a 510(k) for a physical medical device (a powered muscle stimulator). The "acceptance criteria" are implied by the compliance with various international standards and the demonstration of substantial equivalence to predicate devices.

Here's an interpretation of the "acceptance criteria" and "device performance" based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance:

Acceptance Criteria Category	Description & Standard/Reference	Reported Device Performance (Summary)
Biocompatibility	Direct contact components (electrode patches, support belt) must be biocompatible. (Electrode patches cleared under K171381).	Electrode patches are from a qualified supplier with FDA clearance (K171381).
Electrical Safety	Compliance with IEC 60601-1 (General requirements for basic safety and essential performance).	Passed IEC 60601-1.
EMC Safety	Compliance with IEC 60601-1-2 (Electromagnetic compatibility - Requirements and tests).	Passed IEC 60601-1-2.
Specific Safety (Stimulators)	Compliance with IEC 60601-2-10 (Particular requirements for the basic safety and essential performance of nerve and muscle stimulators).	Passed IEC 60601-2-10.
Software Verification	Compliance with FDA Guidance for the Content of Premarket Submission for Software Contained in Medical Devices.	Software verification carried out according to FDA Guidance.
Home Healthcare Environment	Compliance with IEC 60601-1-11 (Requirements for medical electrical equipment and systems used in the home healthcare environment).	Passed IEC 60601-1-11. (Implies suitability for OTC use).
Waveform Output	Output specifications verified according to FDA Guidance for Powered Muscle Stimulator 510(k)s (Load conditions of 0.5kΩ, 2kΩ, 10kΩ).	Graphic waveform, output level, and max charge/current/power calculations recorded and passed. All models exhibit biphasic pulsed symmetric waveforms and consistent output design.
Electrode Patch Performance (Dispersion & Shelf Life)	Verification of current dispersion and shelf life per FDA Guidance Shelf Life of Medical Device and ASTM F 1980-07. Impedance uniformity across active areas.	Current Dispersion: No significant difference in impedance across multiple electrode patches, indicating uniform current distribution. All test results passed. Shelf Life: Test results confirmed.
Output Electrical Parameters	Maximum output voltage, current, average current, phase charge, current density, power density, pulse frequency, and pulse duration within range of predicates and compliant with standards.	All reported values (Mode 1, 2, 3) are within the range of the predicate devices and compliant with IEC 60601-1, IEC 60601-2-10, and FDA Guidance for Powered Muscle Stimulator.
Substantial Equivalence	The device must not raise different questions of safety and effectiveness compared to predicate devices based on intended use, design, specifications, and performance.	Conclusion: The subject device Muscle Trainer is substantially equivalent to the predicate devices.

Regarding the AI/ML-specific questions (2-9), the provided document does NOT discuss an AI/ML component or study of that nature.

The "Muscle Trainer" is a physical medical device (powered muscle stimulator) and the performance data section focuses on electrical safety, EMC, biocompatibility, and output waveform characteristics – typical for hardware-based medical devices seeking 510(k) clearance via substantial equivalence.

Therefore, for questions 2 through 9, the answer is that the provided document does not contain this information as the device is not described as an AI/ML product.

Specifically:

2. Sample sized used for the test set and the data provenance: Not applicable. Performance testing is standard engineering/electrical testing, not a clinical study involving a "test set" of patient data for an algorithm.
3. Number of experts used to establish the ground truth... and the qualifications of those experts: Not applicable. Ground truth as typically understood in AI/ML is not relevant here.
4. Adjudication method: Not applicable.
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.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc): Not applicable.
8. The sample size for the training set: Not applicable.
9. How the ground truth for the training set was established: Not applicable.

This document clearly outlines studies related to compliance with electrical safety standards, biocompatibility of materials, and validation of the device's electrical output parameters against established guidance and predicate devices, which are typical for traditional medical device clearance. It does not mention any AI or machine learning components.

Summary

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Image /page/0/Picture/0 description: The image contains the logo of the U.S. Food and Drug Administration (FDA). On the left is the Department of Health & Human Services logo. To the right of that is the FDA logo, which is a blue square with the letters "FDA" in white. To the right of the blue square is the text "U.S. FOOD & DRUG ADMINISTRATION" in blue.

October 17, 2018

Shenzhen Kentro Medical Electronics Co., Ltd % Rain Yip Registered Engineer Feiying Drug & Medical Consulting Technical Service Group Rm. 3005, Area B, Bldg.1, Southward Ruifeng Business Center, Guimiao Road Shenzhen, Cn 518000 Guangdong

Re: K181728

Trade/Device Name: Muscle Trainer Regulation Number: 21 CFR 890.5850 Regulation Name: Powered Muscle Stimulator Regulatory Class: Class II Product Code: NGX Dated: July 14, 2018 Received: July 17, 2018

Dear Rain Yip:

We have reviewed vour 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. Although this letter refers to your product as a device, please be aware that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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 liability 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

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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); medical device reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.htm); good manufacturing practice requirements as set forth in the quality systems (OS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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 comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).

Sincerelv.

Vivek J. Pinto -S

for Carlos L. Peña, PhD, MS Director Division of Neurological and Physical Medicine Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Indications for Use

510(k) Number (if known) K181728

Device Name Muscle Trainer

Indications for Use (Describe)

To be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

Type of Use (Select one or both, as applicable)

Prescription Use (Part 21 CFR 801 Subpart D)

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

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510(k) Summary

Date: 2018-06-04

I. Submitter

SHENZHEN KENTRO MEDICAL ELECTRONICS CO., LTD

No.3, Xihu Industry Zone, Xikeng Village, Henggang Town, Longgang District, Shenzhen City, Guangdong Province, China

Tel.: +86 755 3382 5998 Tax: +86 755 3382 5996

Zewu Zhang (Management representative) Tel: +86 134 1043 0929 Email: kentro@kentro.com.cn

II. Device

Type of 510(k): Traditional Common Name: Powered muscle stimulator Trade Name: Muscle Trainer Models: KTR-230 series, KTR-231, KTR-232, KTR-233, KTR-234 Classification Name: Stimulator, Muscle, Powered, For muscle conditioning Review Panel: Physical Medicine Regulatory Class: II Product Code: NGX Regulation Number: 21 CFR 890.5850

III. Predicate Device

Applicant		Predicate Device		510(k) Number	Approval Date
WellInternational Ltd.	Brain	(Primary):GYMFORM®ABS &CORE/VDPGYCSET0042		K142055	May 11, 2015
HIVOXINC.	BIOTEK	HIVOX OTC ElectricalStimulator/SEM44		K171803	Nov.29, 2017

IV. Device Description

Muscle Trainer is a product that adopts modern electronic science and technology to delivers electric pulses generated to the user's skin through the electrodes.

Muscle Trainer is mainly composed of the host and electrode patches, as well as it is powered by CR2023 battery. Of which, the electrode patch is cleared in K171381.

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Electric pulse combination, 0~12 levels can be adjusted and chosen according to personal preference.
CR2032 Button batteries (DC3V) power supply, easy to use and safe.

The main differences among them are the followings but not affect its intended use:

Appearance
The number of control button: KTR-230 series, KTR-231 and KTR-232 have two buttons to control: KTR-233 and KTR-234 have three buttons to control.
The number of electrode patch used: KTR-230 series, KTR-233 and KTR-234 are equipped with one electrode patch; KTR-231 is equipped with six electrode patches as well as KTR-232 is equipped with two electrode patches.
Applied parts: KTR-230 series, KTR-233 and KTR-234 apply to abdomen, shoulder, arm, thigh and calf; KTR-231 applies to abdomen in the place where between ribs and hip bones; KTR-232 applies to waist, shoulder, arm, thigh and calf.

V. Indications for Use

To be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

VI. Comparison of Technological Characteristics With the Predicate Devices

The Muscle Trainer is substantially equivalent to the predicated device based on intended use, design, specifications and performance.

The Muscle Trainer does not raise different questions of safety and effectiveness as compared to the predicate devices.

Information for predicate device was obtained from publicly available sources, including the 510(k) Summary and device instruction manual. A technical comparison to the predicate is provided below:

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ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
510(k) number	K181728	K142055	K171803	/
Trade name	MuscleTrainer/KTR-230series,KTR-231, KTR-232, KTR-233,KTR-234	GYMFORM®VDPGYCSET0042	HIVOX OTC ElectricalStimulator/SEM44	/
Product code	NGX	NGX	NUHNGX	/
Indicationforuse/Intended use	To be used to stimulate healthymuscles in order to improve andfacilitate muscle performance.	GYMFORM®ABS& CORE isintended to stimulate healthymuscles in order to improve orfacilitate muscle performance. TheABS& CORE may be considered atechnique or method for muscletraining. 2-area belt is intended foruse on the muscles in abdomen orlower back separately. Mini belt isintended for use on the muscles inarms, legs, thighs or buttocks areasseparately	"HIVOX OTC Electrical Stimulator,SEM44 –TENS: The device is designed to beused for temporary relief of painassociated with sore and achingmuscles in the shoulder, waist, back,neck, upper extremities (arm), lowerextremities (leg), abdomen andbottom due to strain from exercise onormal household work activities.EMS: The device is designed to beused for stimulate healthy muscles inorder to improve and facilitatemuscle performance"	SENOTE 4
Location for use	OTC	OTC	OTC	SE
BASIC UNIT SPECIFICATIOSN
Power supply	2032 Button battery (DC3V)	2 ×1.5V AAA batteries	4.5V (batteries, 3×1.5V AAA)	SE
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
				NOTE 1
Number of outputmodes		3	6	TENS: 15EMS: 35	SENOTE 1
	ChannelNumber	1	2	2	SENOTE 1
Numberof outputchannels	Synchronous orAlternating?	N/A	Alternating	Synchronous	SE
	MethodofChannelIsolation	N/A	Press MODE button for 3 seconds	By electrical circuit and software	SE
Regulated Currentor Voltage?		Regulated Voltage	Regulated Voltage	Regulated Voltage	SE
Software/Firmware/MicroprocessorControl?		Yes	Yes	Yes	SE
Automatic overloadtrip voltage level?		No	No	Yes	SE
Automatic no-loadtrip?		Yes	Yes	Yes	SE
Automatic shut off		Yes	Yes	Yes	SE
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
Patient overridecontrol?	Yes	Yes	Yes	SE
IndicatorDisplay	On/OffStatus?	Yes	Yes	Yes	SE
	LowBattery?	Yes	Yes	Yes	SE
	Voltage/CurrentLevel?	N/A	Yes	Yes	SE
Timer range		Default 15-minute	Default 10-minute	5-100 minutes	SE
Compliancewithvoluntary standards		■ IEC60601-1-2■ IEC60601-1■ IEC60601-1-11■ IEC60601-2-10	■ IEC60601-1-2■ IEC60601-1■ IEC60601-2-10	■ IEC60601-1-2■ IEC60601-1■ IEC60601-2-10	SE
Compliancewith21CFR 898		Yes	Yes	Yes	SE
Dimensions(LWH)		(Host)KTR-230 series: φ51×13.5mmKTR-231: φ51×13.5mmKTR-232: φ51×13.5mmKRT-233: 53.4×47.5×11.8mmKTR-234: 49×49×12.6mm	100mm×68mm×24.5mm	132mm×63mm×29.5mm (includingbelt clip)	SENOTE 2
Weight		(Host)KTR-230 series: 0.6ozKTR-231: 0.6ozKTR-232: 0.6ozKTR-233: 0.6oz	50g (Without batteries)	89g (including belt clip, withoutbatteries)123g (including belt clip andbatteries)	SENOTE 2
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
	KTR-234: 0.56oz
Housingmaterialand construction	ABS	ABS	ABS	SE
OUTPUT SPECIFICATIOSNS
Waveform	Mode 1: Pulsed symmetric, biphasic,square waveMode 2: Pulsed symmetric, biphasic,square waveMode 3: Pulsed symmetric, biphasic,square wave	Symmetrical, rectangular	Biphasic, square	SE
Maximumoutputvoltage	Mode 1:(±10%)Vp36.5V @500Ω58.5V @2kΩ93 V @10kΩMode 2:(±10%)Vp36.5V @500Ω58.5V @2kΩ93 V @10kΩMode 3:(±10%)Vp36.5V @500Ω58.5V @2kΩ93 V @10kΩ	(±10%)Vp66V @ 500 Ω69V @ 2k Ω70V @ 10k Ω	(±10%)Vp50V @ 500 Ω60V @ 2k Ω125V @ 10k Ω	SENOTE 3
Maximumoutput	Mode 1:(±10%) Ip	(±10%)Ip132mA @ 500 Ω	(±10%)Ip100mA @ 500 Ω	SENOTE 3
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
current	73mA @ 500 Ω29.25mA @ 2k Ω9.3mA @ 10k ΩMode 2:(±10%) Ip73mA @ 500 Ω29.25mA @ 2k Ω9.3mA @ 10k ΩMode 3:(±10%) Ip73mA @ 500 Ω29.25mA @ 2k Ω9.3mA @ 10k Ω	34.5mA @ 2k Ω7mA @ 10k Ω	45mA @ 2k Ω12.5mA @ 10k Ω
Net charge (perpulse)	@500ΩMode 1: 0Mode 2: 0Mode 3: 0	19.2μC @ 500 Ω	0.001μC @ 500 Ω	SE
Maximum phasecharge @500Ω	Mode 1: 6.85μC@500 ΩMode 2: 10.11µC@500 ΩMode 3: 10.11µC@500 Ω	16.4µC @ 500 Ω	0.045μC @ 500 Ω	SENOTE 3
Maximum averagecurrent @500Ω	Mode 1: 3.6mA@500 ΩMode 2: 1.1mA@500 ΩMode 3: 5.4mA@500 Ω	2.304mA@500 Ω	13.5mA @ 500 Ω	SENOTE 3
Maximum currentdensity @500Ω	Mode 1:KTR-230series: 0.175mA/cm²@500 ΩKTR-231: 0.050mA/cm²@500 ΩKTR-232: 0.073mA/cm²@500 Ω	0.082mA/ cm²@ 500 Ω	0.667mA/ cm²@ 500 Ω	SENOTE 3
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
Maximumpowerdensity @500Ω	KTR-233: 0.169mA/cm²@500 ΩKTR-234: 0.172mA/cm²@500 ΩMode 2:KTR-230series: 0.053mA/cm²@500 ΩKTR-231: 0.015mA/cm²@500 ΩKTR-232: 0.022mA/cm²@500 ΩKTR-233:0.052mA/cm²@500 ΩKTR-234: 0.053mA/cm²@500 ΩMode 3:KTR-230series: 0.263mA/cm²@500 ΩKTR-231: 0.076mA/cm²@500 ΩKTR-232: 0.109mA/cm²@500 ΩKTR-233: 0.254mA/cm²@500 ΩKTR-234: 0.258mA/cm²@500 ΩMode 1:KTR-230series: 0.0003W/cm²@500 ΩKTR-231: 0.00009W/cm²@500ΩKTR-232: 0.0001W/cm²@500ΩKTR-233: 0.0003W/cm²@500ΩKTR-234: 0.0003W/cm²@500ΩMode 2:KTR-230series:0.00003W/cm²@500 ΩKTR-231: 0.000008W/cm²@500Ω	94.8μW/cm² @ 500 Ω	0.0046μW/cm² @ 500 Ω (average)	SENOTE 3
ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
	KTR-232: 0.00001W/cm2@500ΩKTR-233: 0.00003W/cm2@500ΩKTR-234: 0.00003W/cm2@500Ω
	Mode 3:KTR-230series: 0.0007W/cm2@500ΩKTR-231: 0.0002W/cm2@500ΩKTR-232: 0.0003W/cm2@500ΩKTR-233: 0.0007W/cm2@500ΩKTR-234: 0.0007W/cm2@500Ω
Pulse frequency	Mode 1: 1-120HzMode 2: 1-120HzMode 3: 1-120Hz	2Hz, 10Hz, 50Hz, 90Hz, 120Hz	1-150Hz	SENOTE 3

Pulse duration	Mode 1: 50-200μsMode 2: 50-200μsMode 3: 50-200μs	108μs/124μs	50-450μs	SENOTE 3

	Pulsesper burst	Mode 1: N/AMode 2: N/AMode 3: N/A	1~397	3	SE


BurstMode	Burstspersecond	Mode 1: N/AMode 2: N/AMode 3: N/A	0.125~1	2/60Hz	SE


	Burstduration(seconds)	Mode 1: N/AMode 2: N/AMode 3: N/A	1~8	36ms	SE


	DutyCycle	Mode 1: N/AMode 2: N/A	0.02%~1.28%	36ms/390ms	SE

ComparisonElements	Subject Device	Primary Predicate DeviceK142055	Predicate Device 1K171803
[Line (b)x Line (c)]	Mode 3: N/A
ON Time (seconds)	1s	0.5s	2s	SE
OFF Time(seconds)	<3s	0.5s	2s	SE
ADDITIONAL FEATURES
Environment forOperation	Temperature: 5°C~40°CHumidity: 15%~93%RH	Temperature: 5°C~40°CHumidity: 20%~65%RH	Unknown	SE
Environment forStorage	Temperature: -25°C~70°CHumidity: 0%~93%RH	Temperature: 0°C~40°CHumidity: 10%~90%RH	Unknown	SE
Environment forTransport	Temperature: -10°C~40°CHumidity: 15%~93%RH	Unknown	Unknown	SE

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COMPARISON IN DETAILS:

NOTE 1: Although the Power supply, Number of output modes, Output Intensity Level, Number of output channels and Timer range of the subject devices are a little different from the predicate devices, they are all compliant with the requirements of IEC60601-1-2, IEC60601-1 and Guidance for Powered Muscle Stimulator. So the device does not raise different questions of safety and effectiveness as compared to the predicate devices.

NOTE 2: Although the appearance, weight and dimensions are different between the subject devices and predicate device, these differences are insignificant and do not affectiveness.

NOTE 3: Although the Maximum output voltage, Maximum output current, Maximum average current, Maximum phase charge, Maximum current density, Maximum power density, Pulse frequency and Pulse duration of the subject devices are a little different from the predicate devices, but all are within the range of the predicates and they are all compliant with the requirements of IEC60601-1, IEC60601-2-10, and Guidance for Powered Muscle Stimulator. So the device does not raise different questions of safety and effectiveness as compared to the predicate devices.

NOTE 4: The intended use (indication of use) of the subject device is within the scope of the predicate device K142055, and is the same with the predicate device K171803, model SEM44, mode EMS. This define does not affect the intended use or normal use of the subject device.

CONCLUSION: The subject device Muscle Trainer is substantial equivalent to the predicate devices.

VII.Performance Data

The following performance data were provided in support of the substantial equivalence determination.

1) Biocompatibility Testing

The component of the Muscle Trainer that directly contacting the user is electrode patches and support belt.

Component Name	Material of Component	Body Contact Category	Contact Duration
Electrode patches	EVA foam, Carbon film, conductive hydrogel, PET	Surface-contacting skin	Less than 24hours

The electrode patches are directly purchased from qualified supplier which has obtained FDA clearance with a 510(k) number of K171381 and been legally marketed to U.S. market.

2) Electrical and EMC Safety

Electrical safety and EMC safety testing was performed to, and passed, the following standards:

IEC 60601-1 Medical electrical equipment -Part 1: General requirements for basic safety and essential performance
IEC 60601-1-11 Medical electrical equipment -Part 1-11: General requirements for basic safety and essential performance -Collateral standard: Requirements for medical electrical equipment and medical electrical systems used in the home healthcare environment

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IEC 60601-2-10 Medical electrical equipment -- Part 2-10: Particular requirements for the basic safety and essential performance of nerve and muscle stimulators
IEC 60601-1-2 Medical electrical equipment -Part 1-2: General requirements for basic safety and essential performance -Collateral standard: electromagnetic compatibility -Requirements and tests

In addition to the compliance of voluntary standards:

The software verification has been carries out according to the FDA Guidance for the Content of Premarket Submission for Software Contained in Medical Devices.
The waveform test report has also been conducted to verify the output specifications of the subject device according to the FDA Guidance for Powered Muscle Stimulator 510(k)s: Load conditions of 0.5kΩ, 2kΩ and 10kΩ were tested, graphic waveform, output level and maximum charge/current/power calculation is recorded in this report. The outputs of the device models all are biphasic pulsed symmetric waveform, and have the same output design, such as output voltage and current, frequency, pulse duration and so on.
The verification report of dispersion and shelf life has been conducted to verify the current dispersion and shelf life of the electrode patch equipped according to the FDA Guidance Shelf Life of Medical Device and ASTM F 1980-07 standard:
- 1. Under the specified conditions, test and record the current dispersion of electrode patch and check the impedance on several places of the active areas of the patch to ensure it is distributing current uniformly, as well as the shelf life and the service life of the electrode patch are judged by comparing the test results. All test results are passed.
- 1. First the data and analysis from Electrode patch dispersion and shelf life testing of KTR-231 and KTR-230 proves that there is no significant difference between the impedances of each point of 6 electrode patches connected to 1 channel, which is the same as 2 electrode patches to 1 channel. That means the current dispersion of each point of 6 electrode patches distributes uniformly. Therefore, 6 patches only differ in area from 2 patches, which are equivalent to 1 large pad made of 6 single same patches together. Second the maximum current density of model KTR-231, decided by the quantity and area of electrode pads, voltage, is less than 0.6(W/cm2). Third KTR-231 complies with the requirements of IEC 60601-1, IEC 60601-1-2 and IEC 60601-2-10. Therefore, the difference does not present different questions of safety.
- 1. Moreover, it is not the specifications about effectiveness, the maximum output voltage and current of model KTR-231 is equivalent to predicate device, thus the difference does not present different questions of effectiveness.

Summary

Based on the above performance as documented in this application. Muscle Trainer was found to have a safety and effectiveness profile that is similar to the predicate device.

VIII. Conclusions

The subject device Muscle Trainer is to be concluded substantial equivalent to its predicate devices.

Regulation Number and Section

§ 890.5850 Powered muscle stimulator.

(a)
Identification. A powered muscle stimulator is an electrically powered device intended for medical purposes that repeatedly contracts muscles by passing electrical currents through electrodes contacting the affected body area.(b)
Classification. Class II (performance standards).