The Innovative Neurotronics WalkAide External Functional Neuromuscular Stimulator (WalkAide System) is intended to address the lack of ankle dorsiflexion in patients who have sustained damage to upper motor neurons or pathways to the spinal cord. During the swing phase of gait, the WalkAide System electrically stimulates the appropriate muscles that cause ankle dorsiflexion and may thus improve the patient's gait. Medical benefits of Functional Electrical Stimulation (FES) may include prevention/ retardation of disuse atrophy, increased local blood flow, muscle re-education, and maintained or increased joint range of motion.

Device Description

The WalkAide is an external functional electrical stimulator. It is a small device that attaches to the leg just below the knee, near the head of the fibula. During a gait cycle, the WalkAide stimulates the common peroneal nerve, which innervates the tibialis anterior and other muscles that cause dorsiflexion of the ankle. The WalkAide System consists of the WalkAide Patient Kit and the WalkAide Clinician Kit . The WalkAide Patient Kit comprises of all the components and accessories that the patient will take home and use. The Clinician System comprises the accessories that a clinician (i.e., orthotic specialist, physiotherapist, occupational therapist, etc.) will use to set up a patient's WalkAide.

AI/ML Overview

The provided text describes a 510(k) summary for the Innovative Neurotronics, Inc. WalkAide System, which is an external functional neuromuscular stimulator. The summary focuses on demonstrating substantial equivalence to predicate devices, particularly regarding changes in output specifications (voltage, pulse width, and addition of ramp modulation).

Here's an analysis of the acceptance criteria and the "study" (which in this context refers to the technical comparison and testing described for regulatory approval):

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are not explicitly stated in a quantifiable manner as "acceptance criteria" for a study in the typical sense of clinical trials. Instead, the document frames "acceptance" as meeting applicable safety and performance standards (like IEC 60601-2-10) and being substantially equivalent to predicate devices. The "reported device performance" refers to the technical specifications and measured values of the proposed WalkAide (K123972) and a comparison to its predicate (K052329) and other competitive devices (Bioness L300 Plus, Odstock Pace).

Below is a table summarizing key electrical output criteria and the proposed device's performance, as derived from the "Predicate Comparison Table" and the "Discussion of Table 6.1 equivalent parameters" section.

Feature	Acceptance Criteria (typically derived from standards or predicate equivalence)	Proposed WalkAide (K123972) Performance (Measured/Computed)	Comparison/Comments
Output Stage Type	Must be suitable for functional electrical stimulation, comparable to predicates (Constant Voltage or Constant Current).	Constant Voltage (Adjustable)	Identical to previous WalkAide. Predicates Bioness & Odstock are Constant Current. Considered equivalent in functionality.
Output Voltage Range	Safe and effective range, within the scope of predicate devices (e.g., similar to Bioness 120V or Odstock's 100±10%V @ 1000 Ohms).	0 - 110V (±10%) at 1000 Ohms load	Within range of Bioness (120V) and Odstock Pace (100±10%V).
Max Output Current (500Ω)	Should not exceed limits defined by applicable standards (e.g., IEC 60601-2-10 paragraph 51.104 for rms current, and general safety). Comparable to predicate devices.	<206.8 mA peak (specification limit); 14.2 mA rms max (measured)	Measured rms current (14.2 mA) is in the same range as Bioness (13.1 mA rms) and less than Odstock (20.6 mA rms). Meets the 50 mA rms limit of IEC 60601-2-10 (paragraph 51.104).
Max Output Voltage (1000Ω)	Safe output voltage, comparable to predicates (e.g., Bioness 120Vpk, Odstock 108Vpk).	121 V max (specification limit); <121 V peak (specification limit)	Proposed 121V is within <1% of Bioness (120Vpk). Meets IEC 60601-2-10 specification limit of 500V peak. With 1M Ohm load, proposed is <150V (measured 123V), comparable to Odstock (measured 150V).
Ramp Modulation	Presence of ON/OFF ramp features comparable to competitive devices.	Yes (ON Ramp 0-0.5s, OFF Ramp 0-0.5s in 0.1s steps)	Added feature, shown to be equivalent to ramping in Bioness L300 Plus (0-2s) and Odstock Pace (0-2s).
Pulse Duration	Safe and effective range, comparable to predicate devices (e.g., Bioness 100-300 µs, Odstock 0-360 µs).	25-300 microseconds (±5% or ±7 µs); adjustable in discrete steps: 25, 50, 100, 150, 200, 250, and 300 µs.	Proposed max (300 µs) is equal to Bioness and less than Odstock (360 µs). Proposed min (25 µs) is within Odstock range (0-360 µs). Considered equivalent.
Frequency Range	Safe and effective range, comparable to predicate devices.	16.7, 20.0, 25.0, and 33.3 pulses per second (Hz)	Identical to parent device. Considered essentially equivalent to Bioness (20-45 pps) and Odstock (20-60 pps).
Max Phase Charge (500Ω)	Must be below published safety limits (e.g., 75 µC for ANSI/AAMI NS4-1985). Comparable to predicate devices.	41.2 MicroCoulombs (µC) measured	Significantly lower than the 75 µC safety limit (ANSI/AAMI NS4-1985). Equivalent to Odstock (41 µC).
Max RMS Current Density	Must be within safety limits derived from applicable standards (e.g., 6.32 mA rms/cm² from IEC 60601-2-10 50 mA rms limit, or 7.95 mA rms/cm² from FDA guidance 0.25 W/cm² limit).	1.80 mA rms/cm² measured	Below derived safety limits (6.32 mA rms/cm² from IEC 60601-2-10; 7.95 mA rms/cm² from FDA guidance). Higher than Odstock/Bioness (0.82 mA rms/cm²), but still deemed safe.
Max Average Power Density	Must be below safety limits (e.g., 0.25 Watts/cm² from FDA guidance, or 0.16 Watts/cm² from IEC 60601-2-10 50 mA rms limit). Comparable to predicate devices.	0.027 Watts/cm² max (computed assuming square pulse); 0.0128 Watts/cm² (measured using rms current levels)	Measured power density (0.0128 W/cm²) is an order of magnitude below the FDA limit (0.25 W/cm²).
Compliance with Standards	Compliance with relevant electrical safety and performance standards (e.g., IEC 60601-1, IEC 60601-1-2, IEC 60601-2-10, 21 CFR 898).	IEC 60601-1 3rd Ed, IEC 60601-1-2:2007, IEC 60601-2-10:1987+A1, 21 CFR 898. "V012 "WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10."	Updated to newer editions of general standards (IEC 60601-1 3rd Ed, IEC 60601-1-2:2007), maintaining compliance with the specific medical device standard (IEC 60601-2-10).

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

This document describes a premarket notification (510(k)) based on substantial equivalence, not a clinical trial with a "test set" in the traditional sense of patient data. The "test set" here refers to the extensive technical testing and benchmarking performed to assess the electrical and functional characteristics of the device against established standards and predicate device specifications.

Sample Size for Test Set: The document does not specify a "sample size" of patients or data points for a clinical test set. The evaluation is based on technical specifications, direct measurements, and comparisons of the device's electrical output to standards and predicate devices. For example, voltage and current measurements are taken on the device itself under specified load conditions.
Data Provenance: The data primarily comes from bench testing and technical performance evaluations of the WalkAide (K123972) and its predicate (K052329). The comparative data for Bioness L300 Plus and Odstock Pace is extracted from their respective 510(k) summaries or available specifications. This is not patient-derived data (retrospective or prospective) in the context of clinical outcomes. The document repeatedly refers to "V012 'WalkAide Performance Test Protocol'" as the method used to validate the device's adherence to applicable requirements of IEC 60601-2-10.

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

In this 510(k) context, "ground truth" for the test set is established by the applicable international and national consensus standards (e.g., IEC 60601 series, ANSI/AAMI NS4-1985) and the specifications of legally marketed predicate devices.

Number of Experts: Not applicable in the sense of a panel of clinical experts defining ground truth for patient outcomes. The "experts" are the engineers, regulatory specialists, and standards committees who developed and codified the safety and performance standards.
Qualifications of Experts: The experts who establish these standards typically include biomedical engineers, physicians, regulatory scientists, and other specialists with deep knowledge of medical device safety and efficacy, functional electrical stimulation, and relevant biophysical principles. The document itself does not specify the qualifications of individuals involved in the actual testing or in its submission from Innovative Neurotronics, Inc., beyond identifying a "Director of Quality and Regulatory."

4. Adjudication Method for the Test Set

Not applicable in the sense of clinical adjudication. The "adjudication" is essentially the regulatory approval process by the FDA, which reviews the submitted data and arguments for substantial equivalence against its own internal expertise and guidance. The technical validation is done by demonstrating compliance with established standards and direct comparative analysis against predicate device specifications, without an external adjudication panel for the technical results.

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

No MRMC study was done, nor is it applicable. This device is an external functional neuromuscular stimulator, not an imaging or diagnostic AI device that involves "human readers" or "AI assistance" in interpretation. The product directly provides therapeutic stimulation.

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done

Not directly applicable as an "algorithm only" study. The device itself is designed to function largely automatically based on configurable parameters set by a clinician and using integrated sensors (tilt or foot sensor). The performance described in the document is the standalone device performance (electrical output, safety parameters) rather than an isolated algorithm. The "human-in-the-loop" aspect exists during the initial setup by a clinician and ongoing patient use, but the core performance data presented is about the device's physical output characteristics.

7. The Type of Ground Truth Used

The "ground truth" used for this submission is primarily:

Established safety and performance standards: Such as IEC 60601-2-10, IEC 60601-1, IEC 60601-1-2, ANSI/AAMI NS4-1985, and FDA guidance documents (e.g., "Guidance Document for Powered Muscle Stimulator 510(k)s").
Specifications and demonstrated performance of legally marketed predicate devices: The historical data and approved specifications of the parent WalkAide (K052329), Bioness L300 Plus (K103343), and Odstock Pace (K102115) form the comparative basis for "ground truth" for substantial equivalence.

This is a regulatory "ground truth" for device approval, not a clinical "ground truth" based on pathology or outcomes data.

8. The Sample Size for the Training Set

Not applicable. This document describes a 510(k) submission for a physical medical device, not a machine learning or AI algorithm that requires a "training set" of data. No training set was used.

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

Not applicable, as no training set was used.

Summary

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

510(k) Summary for the Innovative Neurotronics, Inc. WalkAide System K123972

1. SPONSOR

Innovative Neurotronics, Inc. 3600 N. Capital of Texas Highway Bldg. B, Suite 150 Austin, Texas 87846

Contact Person: Glen Neally – Director of Quality and Regulatory Telephone: 1-512-721-1903 Fax 1-512-721-1939

Date Prepared: December 21, 2012

2. DEVICE NAME

Proprietary Name:	WalkAide
Common/Usual Name:	External Neuromuscular Functional Stimulator
Classification Names:	External Neuromuscular Functional Stimulator
Classification Number:	21 CFR 882.5810
Product Code:	GZI

3. PREDICATE DEVICES

Proprietary Name	510(k)	Product Code	Manufacturer
WalkAide System	K052329	GZI	Innovative Neurotronics, Inc.
NESS L300	K103343	GZI, IPF	Bioness Inc.
ODFS PACE	K102115	GZI	Odstock Medical LTD

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

4. INTENDED USE

DEVICE DESCRIPTION ട.

6. BASIS FOR SUBSTANTIAL EQUIVALENCE

WalkAide, Odstock and the Bioness L300 are designed to meet the applicable requirements of IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators." Not all of this standard is applicable since the standard applies to line powered devices and the WalkAide is powered by one AA batteries. V012 " WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10. When this protocol is run it validates that the WalkAide meets the applicable design requirements of IEC 60601-2-10.

There are basically three changes in Output Specification between the parent WalkAide (K052329) device and the proposed WalkAide (K123972) device: 1) output voltage, 2) output pulse width, and 3) addition of Ramp Modulation (Ramp Up and Ramp Down).

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

applicable clauses of IEC 60601-2-10 "Particular Requirements for the Safety of Nerve and Muscle Stimulators". V012 " WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10. The addition of Ramp Up and Ramp Down is equivalent to the ramping of the Bioness and Odstock devices.

For similarities and differences please review the following predicate comparison table:

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

FEATURE	INNOVATIVENEUROTRONICS, INC.WALKAIDEK052329SUMMARY STATEMENTThe Innovative NeurotronicsWalkAide External FunctionalNeuromuscular Stimulator(WalkAide System) is intended toaddress the lack of ankledorsiflexion in patients who havesustained damage to upper motorneurons or pathways to the spinalcord. During the swing phase ofgait, the WalkAide Systemelectrically stimulates theappropriate muscles that cause ankledorsiflexion and may thus improvethe patient's gait. Medical benefitsof Functional Electrical Stimulation(FES) may include prevention/retardation of disuse atrophy,increased local blood flow, musclere-education, and maintained orincreased joint range of motion.Intended Use	BIONESS L300 PLUSK103343SUMMARY STATEMENTThe NESS L300 Plus System isintended to provide ankledorsiflexion and kneeflexion or extension in individualswith foot drop and thigh muscleweakness,following an upper motor neuroninjury or disease. During gait, theL300 PlusSystem electrically stimulatesmuscles in the affected leg toprovide dorsiflexion ofthe foot and knee flexion orextension, thus it may improve theindividual's gait. TheL300 Plus System may also:* Facilitate Muscle re-education* Prevent/retard disuse atrophy* Maintain or increase joint range ofmotion* Increase local blood flow	ODSTOCK PACEK102115SUMMARY STATEMENTThe ODES® Pace is intended toprovide ankle dorsiflexion inindividuals who have adropped foot as a consequence ofupper motor neuron injury. Bydetecting the swingphase of gait through a foot switchsignal, appropriate electricalstimulation of the leg and anklemuscles may improve gait byflexing the foot of persons who havelost or impaired function. Theremay be additional benefits fromFES such as muscle re-education,prevention/retardation of disuseatrophy, increased or maintainedrange of joint motion and increasein local blood flow.	INNOVATIVENEUROTRONICS, INC.WALKAIDE PROPOSEDK123972SUMMARY STATEMENTThe Innovative NeurotronicsWalkAide External FunctionalNeuromuscular Stimulator(WalkAide System) is intended toaddress the lack of ankledorsiflexion in patients who havesustained damage to upper motorneurons or pathways to the spinalcord. During the swing phase ofgait, the WalkAide Systemelectrically stimulates theappropriate muscles that cause ankledorsiflexion and may thus improvethe patient's gait. Medical benefitsof Functional Electrical Stimulation(FES) may include prevention/retardation of disuse atrophy,increased local blood flow, musclere-education, and maintained orincreased joint range of motion.	COMPARISON
Power Source	1.5 V AA Battery(not rechargeable)	CU - Rechargeable AAAStim - Rechargeable LilonGait Sensor – CR2430 coincell	PP3, 9V Battery	1.5 V AA Battery(not rechargeable)	IdenticalEquivalent
Microprocessor Controlled	Yes	Yes	Yes	Yes	Identical
Indicators
Unit functioning	Yes	Yes	Yes	Yes	Identical
Low Battery	Yes	Yes	Yes	Yes	Identical
Patient Device Set-up andTraining	Done by a clinician using aNotebook/Tablet PC	All the set-up is donethrough a PDA	All the set-up is donethrough the unit	Done by a clinician using aNotebook/Tablet PC	Identical
FEATURE	INNOVATIVENEUROTRONICS, INC.WALKAIDEK052329	BIONESS L300 PLUSK103343	ODSTOCK PACEK102115	INNOVATIVENEUROTRONICS, INC.WALKAIDE PROPOSEDK123972	COMPARISON
Number of Output Modes	1	2	2	1
Channels	1	1	1	1	Identical
Output Stage
Type	Constant Voltage(Adjustable)	Constant Current	Constant Current	Constant Voltage(Adjustable)
Range/Accuracy	0 - 78 V (±5%)	0 - 80 mA in 1mA steps	10--100 mA ±10% into a1000 ohm loadApprox 4% steps	0 - 110V (±10%)
Load	1000 Ohm load	<120VMax Load 5000 ohm(subject to Max VoltageLimitation)	10 to 110 V (Calculated)	1000 Ohm load
Max Output Current	115 mA peak (±5%) @500 Ohm load(max specification limit)	80 mA pk @ 500 Ohm load(measured)	176 mA pk @ 500 Ohm load(measured)	<206.8 mA peak @500 Ohm load (maxspecification limit)
IEC 60601-2-10	11.0 mA rms max @ 500ohm(Computed based on115 mA (+5%), squarepulse)	13.14 mA rms max @ 500ohm(Computed based on 80 mAsquare pulse)	25.8 mA rms max @ 500ohm(Computed based on 176mA square pulse)	20.7 mA rms max @ 500ohm(Computed based on 206.8mA square pulse)
Specification of 50mA rmsMax)	8.8 mA rms max @ 500ohm (measured)	13.1 mA rms max @ 500ohm (measured)	20.6 mA rms max @ 500ohm (measured)	14.2 mA rms max @ 500ohm(measured)(IEC 60601-2-10Specification of 50mA rmsMax)	Equivalent
	78 mA peak (±5%),1000 Ohm load(max specification limit)	80.7 mA pk @ 1000 Ohmload(measured)	110 mA pk @ 1000 Ohmload(measured)	<121 mA peak @ 1000 Ohmload(max specification limit)
Max Output Voltage	78 V1000 Ohm load	80.7 Vpk @ 1K assym(meas)	108 Vpk @ 1K assym(meas)	121 V max1000 Ohm load
IEC 60601-2-10	161.4 Vp-p @ IK sym(meas)	161.4 Vp-p @ IK sym(meas)	216 Vp-p @ IK sym (meas)	(IEC 60601-2-10Specification limit of 500 VPeak)	Equivalent
Specification limit of 500 VPeak)	<150 V1M Ohm load	120 pk @ IM assym (meas)	150V pk @ 1M assym(meas)	Spec limit <150 V1M Ohm load	Identical
		240 Vp-p @ IM sym (meas)	350 Vp-p @ 1M sym (meas)	123V pk @ 1M (meas)
FEATURE	INNOVATIVENEUROTRONICS, INC.WALKAIDEK052329	BIONESS L300 PLUSK103343	ODSTOCK PACEK102115	INNOVATIVENEUROTRONICS, INC.WALKAIDE PROPOSEDK123972	COMPARISON
Ramp Modulations (for gait)ON Ramp	No	Yes0 to 2 sec in 0.1 sec steps	Yes0 to 2 sec in 0.05 sec steps	Yes0 to 0.5 sec in 0.1 sec steps	Equivalent
Ramp Up Time
OFF Ramp	No	Yes0 to 2 sec in 0.1 sec steps	Yes0 to 2 sec in 0.05 sec steps	Yes0 to 0.5 sec in 0.1 sec steps	Equivalent
Ramp Down Time
Waveform	Monophasic or Biphasic	Biphasic	Balanced Biphasic	Biphasic	Identical
Symmetrical orAsymmetrical Shape	Asymmetrical	Symmetrical orAsymmetrical	Symmetrical orAsymmetrical	Asymmetrical	Equivalent
Pulse Duration	50-250 microseconds$\pm$ 5% (Adjustable)Pulse duration adjustable infollowing discrete steps: 50,100, 150, 200, and 250 µs	100-300 microseconds in100 microsecond steps	0-360 microseconds $\pm$ 10%in 3.6 µs steps	25-300 microseconds.Accuracy $\pm$ 5% or $\pm$ 7microseconds, whichever isgreater. Pulse durationadjustable in followingdiscrete steps: 25, 50, 100,150, 200, 250, and 300 µs	Equivalent
Frequency Range(Pulses per second)	16.7, 20.0, 25.0, and 33.3pulses per second (Hz)	20 to 45 pps in 5 pps steps	20 to 60 pps $\pm$ 10% in 5 ppssteps	16.7, 20.0, 25.0, and 33.3pulses per second (Hz)	Identical
Time Between Rising Edgeof Pulses	Time adjustable in followingdiscrete steps: 30, 40, 50,and 60 ms. Accuracy $\pm$ 5ms	Based on frequency of 20 to45 Hz in 5 Hz steps	Based on frequency of 20 to60 Hz in 5 Hz steps	Time adjustable in followingdiscrete steps: 30, 40, 50,and 60 ms. Accuracy $\pm$ 5ms	Identical
Stimulation Trigger Source(When used for gait)	Tilt Sensor or Foot Sensor	Foot Sensor	Foot Sensor	Tilt Sensor or Foot Sensor	Identical
Tilt Detection	Tilt angles between -15 and35 degrees are capable ofbeing detected by the tiltsensor.	No	No	Tilt angles between -15 and35 degrees are capable ofbeing detected by the tiltsensor.	Identical
Burst (exercise) Mode (Y/N)Pulses/burst	YesBurst length and ppsdependent	YesBurst length and ppsdependent	YesBurst length and ppsdependent	YesBurst length and ppsdependent	Identical
Burst/sec	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Identical
Burst duration	1 to 5 sec in 1 sec steps	4 to 20 sec in 1 sec steps	1 to 10 sec in 1 sec steps	1 to 5 sec in 1 sec steps	Identical
Duty cycle	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Depends on ON and OFFtimes	Identical
FEATURE	INNOVATIVENEUROTRONICS, INC.WALKAIDEK052329	BIONESS L300 PLUSK103343	ODSTOCK PACEK102115	INNOVATIVENEUROTRONICS, INC.WALKAIDE PROPOSEDK123972	COMPARISON
Stimulation duration whenused for gait	Dependent on length andspeed of stride <3 secMax settable from 0.1 to 3seconds, 0.1 secondresolution	Max settable from 2 to 10seconds, I second resolution	Max settable from 0.3 to 6seconds ±10% in 50 mssteps	Dependent on length andspeed of strideMax settable from 0.1 to 3seconds, 0.1 secondresolution	Identical
Max. Burst Duration(Seconds)	<5 exercise mode	10	6	<5 exercise mode	Identical
Timer Range (in exercisemode)
ON Time	1 to 5 sec in 1 sec steps	4 to 20 sec in 1 sec steps	1 to 10 sec in 1 sec steps	1 to 5 sec in 1 sec steps
Off Time	1 to 10 sec in 1 sec steps	4 to 60 sec in 1 sec steps	1 to 10 sec in 1 sec steps	1 to 10 sec in 1 sec steps
Total Duration	1 to 30 min in 1 min steps	5 to 60 min in 5 min steps	5 to 100 min in 5 min steps	1 to 30 min in 1 min steps	Equivalent
Max Phase Charge:500 Ohms:	24 microCoulombs	24.0 microCoulombsmeasured	41 microCoulombs measured	41.2 microCoulombsmeasured
1K Ohms:	17 microCoulombs	24.5 microCoulombsmeasured	30 microCoulombs measured	28.0 microCoulombsmeasured
Maximum RMS CurrentDensity	1.39 mA rms/cm² max(Computed based on squarepulse)	0.83 mA rms/cm² max(Computed based on 80 mAsquare pulse)	1.03 mA rms/cm² max(Computed based on 176mA square pulse)	2.62 mA rms/cm² max(Computed based on squarepulse)	Equivalent
Computed limit of 6.32mA rms/cm² based on IEC60601-2-10 max currentlimit of 50 mA rms)	1.1 mA rms/cm² measured	0.82 mA rms/cm² measured	0.82 mA rms/cm² measured	1.80 mA rms/cm² measured(Computed limit of 6.32mA rms/cm² based on IEC60601-2-10 max currentlimit of 50 mA rms)	Equivalent
Max. Average Power Density(FDA "Guidance Documentfor Powered MuscleStimulator 510(k)s" June 9,1999 max limit of 0.25Watts/cm²)	0.012 Watts/cm²(Using 500 Ohm)			0.027 Watts/cm² max @ 500ohms(Computed based on squarepulse)	Equivalent
Computed limit of 0.16Watts/cm² based on IEC60601-2-10 max currentlimit of 50 mA rms)	0.00490 Watts/cm² @ 500Ωmeasured	0.00536 Watts/cm² @ 500Ωmeasured	0.00848 Watts/cm² @ 500Ωmeasured	0.0128 Watts/cm² @ 500ΩMeasured(FDA "GuidanceDocument for PoweredMuscle Stimulator510(k)s" June 9, 1999 maxlimit of 0.25 Watts/cm²)
Electrode Size and Shape(smallest recommended)	3.175 cm (1.25 inches)diameter	45mm diameter	50 mm x 50 mm	3.175 cm (1.25 inches)diameter	Identical
Electrode material(basic mechanical element)Material contacting skin	RoundHydrogel and Stainless Steel(SS) 316	RoundHydrogel	SquareHydrogel and Stainless Steel	RoundHydrogel and Stainless Steel(SS) 316	Identical
Housing Material	ABS	Unknown	Unknown	ABS	Identical
Shipping and storage	Temp: -20 to +60 degrees CRelative Humidity: 95%max, non-condensing	Temp:-20° to 70° CHumidity: 25% to 85%Atmospheric Pressure:900hPa to 1060hPa	Temp: 0° to 40° CHumidity: 35% to 50%	Temp: -20 to +60 degrees CRelative Humidity: 95%max, non-condensing	Identical
Operating	Temp: 0-40 degrees CAltitude: from -400 to 2,400meters (-1300 to 8,000 ft)Relative Humidity: 0 to95%, non-condensing	Temp: 5° to 40° CHumidity: 25% to 85%Atmospheric Pressure:900hPa to 1060hPa	Temp: 5° to 27° СHumidity: 35% to 50%	Temp: 0-40 degrees CAltitude: from -400 to 2,400meters (-1300 to 8,000 ft)Relative Humidity: 0 to95%, non-condensing	Identical
Auto Overload Trip	No	No	No	No	Identical
Auto No-load Trip	No	No	No	No	Identical
Auto Shutoff	No	No	Yes, after 4 hours in standby	No	Identical

す

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

1999 - 1999 - 1999

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

. .

and the comments of the country

{6}------------------------------------------------

. . .

{7}------------------------------------------------

・

{8}------------------------------------------------

Patient Override Control	Manual amplitude Control Knob	Intensity adjustment buttonsand ON/OFF button	Amplitude control knob andpause button	Manual amplitude ControlKnob
Voltage/Current LevelIndicator	Yes	Yes	Yes	Yes	Identical
Weight	4 oz including battery	Control UnitRF Stim UnitGait Sensor	112gm including battery	4 oz including battery	Identical
Dimensions	2.4"x3.25"x0.81"	Control Unit71x46x17.5mmRF Stim Unit74x43x15mmGait Sensor80x50x10mm	72 x 62 x 26 mm	2.4"x3.25"x0.81"	Identical
Compliance withVoluntary Standards	IEC 60601-1 2nd Ed	IEC 60601-1:2003	ISO 60601-1-1:2006	IEC 60601-1 3rd Ed	Identical
	IEC 60601-1-2:2001	IEC 60601-2-10:1987+A1	ISO 60601-1-2:2007	IEC 60601-1-2:2007
	IEC 60601-2-10:1987+A1	Unknown	ISO 60601-2-10:2001	IEC 60601-2-10:1987+A1	Identical
Compliance with 21 CFR898	Yes		Unknown	Yes	Identical

Sample Calculations

Maximum RMS Output Current at 500 ohms
Assume a square pulse of height H, width W, Frequency F, Ioad resistance R, and electrode arca A:
Irms = √((H/R) -W.F) = √((103.4/500) ²-(300c-6)-33.3) = 20.7 mA rms
Maximum RMS Current Density at 500 ohms
Imax,ms= Irms/A = 20.7/7.9cm2 = 2.62 mA rms/ cm1
Maximum Average Power Density at 500 ohms .
Pavg = I²R.W.F/A = (H/R)² RW.F/A = (103.4/500)²-500-(300e-6)-33.3/7.9cm² = 0.027 Watts/ cm³
Max RMS Current Density based on IEC 60601-2-10 limit of 50 mA RMS .
Irmsms = 50 mA rms/electrode area = 50 mA rms/7.917cm² = 6.32 mA rms/cm²
Max RMS Current Density based on FDA "Guidance Document for Powered Muscle Stimulator 510(k)s" June 9, 1999 limit of 0,25 Watts/cm³ .
Irmsms = ( v0.25 Watts/cm² A/R)/A = ( v0.25 Watts/cm²+7.917/500)/7.917 = 7.95 mA rms/cm²
Max Average Power Density based on IEC 60601-2-10 limit of 50 mA RMS (0.05A rms) .
Pavg = 12+R/A = .05*.05*500/7.917 cm2 = 0.16 Watts/cm

ರಿ

{9}------------------------------------------------

Discussion of Table 6.1 equivalent parameters

Output Stage

The Constant Voltage output (Adjustable) is 0 - 110 Volts (±10%) compared to the parent at 0 - 78 Volts (±5%) at 1000 Ohms load. The proposed output voltage is within the range of the Bioness (K103343) approved device which has an output of 120 volts. The Odstock Pace (K102115) delivers up to 100mA +/- 10% into 1000 ohms, which equates to an output voltage of 100 +/-10% Volts. The output of the proposed device is within the range of the Bioness device.

Maximum Output Current

The specification peak output current of the proposed device at 500 ohms is 206.8 mA compared to 120.8 mA for the parent device and at 1000 ohms it is 121 mA compared to 78 mA. For comparison purposes there are no equivalent parameters provided by the competitive devices; however, measured peak current at 500 ohms of the Bioness device is 80 mA and the Odstock device is 176 mA. These peak values do not accurately reflect the effective current, or actual energy delivered to the patient, of the devices since, particularly for the proposed, parent, and Odstock devices, the waveforms are not a simple square wave. In the case of the proposed device the output voltage rapidly rises to the peak value at the start of the stim pulse then gradually slopes downward - for instance, at the end of a 300us pulse the current is approximately 45% of the peak value (refer to waveforms in tab 14. As an example, the same peak current value would be measured for a waveform that maintains a constant current of 100mA for the duration of the stim pulse and a waveform that has a current of 10 mA for 95% of the pulse with a transient of 100mA for the remaining 5%. These two waveforms would, however, deliver substantially different levels of energy to the patient.

A much more important measure of the effectiveness of the output current in delivering energy to the patient is the rms current level. The rms current level takes into account the actual waveform shape and duty cycle. In the Max Current Section of following table the bold values list the measured rms current levels for the four devices and should be used for a more accurate comparison of the maximum effective energy transferred to the

{10}------------------------------------------------

patient. The measured rms current level for the proposed device at 500 ohms is 14.2 mA rms, as compared to 20.6 mA rms for the Odstock device and 13.1 mA rms for the Bioness device. The rms current level for the proposed device is actually less than the Odstock device and in the same range as the Bioness device. These levels meet the 50 mA rms limit specified in paragraph 51.104 of IEC 60601-2-10. The modification does not raise any safety or effectiveness issues since it meets the applicable requirements of IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators." V012 " WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10

Maximum Output Voltage

The Max Output Voltage (baseline to peak; load) is 121 Volts at 1000 Ohms load compared to the parent device at 78 Volts at 1000 ohms load. The waveforms of the parent and proposed devices have the characteristic of rapidly rising to the peak value then gradually decreasing to a significantly lower value at the end of the pulse. The proposed device Max Output Voltage of 121 Volts at 1000 ohms is within <1% of the Bioness (K103343) approved device which has a stated output maximum of 120 volts. There is no stated tolerance on the Bioness voltage specification. With a 1 megohm load the specified maximum output voltage of the proposed device is less than 150V with a measured maximum of 123V while the measured maximum of the Odstock device is 150V.

On Ramp and OFF Ramp

The ON Ramp and OFF Ramp features have been added to the proposed device. The ON Ramp Feature has been added to optionally help with patient muscle spasticity (tone) or rapid toe lift during onset of stimulation during the patient gait cycle. During the Ramp Up time the intensity of the stimulation pulse is gradually increased over the first few seconds of stimulation. OFF Ramp has been added to optionally help with patient toe slap at the end of stimulation in the patient gait cycle. During the Ramp Down time, the intensity of the stimulation pulses in gradually decreased at the end of stimulation in the patient gait cycle. The ON Ramp and OFF Ramp features of the proposed device are equivalent to the ON Ramp and OFF Ramp features in the Bioness L300 Plus (K103343) and the Odstock Pace (K102115).

Pulse Duration

The proposed Pulse Duration is 25-300 microseconds ± 5% (Adjustable)

{11}------------------------------------------------

compared to the parent device of 50-250 microseconds ± 5% (Adjustable). The proposed maximum pulse duration at 300 microseconds is equal to or less than other approved devices (Bioness at 300 microseconds and Odstock at 360 microseconds). The proposed minimum pulse duration of 25 microseconds is within the range of the Odstock at 0 - 360 microseconds. This is equivalent to the predicate devices.

Frequency Range

The proposed device and the parent device output pulse frequency range is selectable between 16.7, 20, 25, and 33.3 pps. The Bioness device range is selectable from 20 to 45 pps in 5 pps steps and the Odstock is selectable from 20 to 60 pps in 5 pps steps. The proposed device is identical to the parent device and is essentially equivalent to the other predicate devices.

Maximum Phase Charge

The measured Maximum Phase Charge at 500 ohms load is 41.2 MicroCoulombs (uC) compared to 24 uC for the parent device, and at 1000 ohms load is 28 µC compared to 17 µC. The maximum phase charge of 41.2 uC for the proposed device is significantly lower than the maximum safety limit of 75 µC specified in paragraph 3.2.2.2 of ANSI/AAMI NS4-1985, "American National Standard for Transcutaneous Electrical Nerve Stimulators." For comparison purposes there are no equivalent parameters provided by the competitive devices. However, the measured phase charge of the Odstock device at 500 ohms is 41 µC as compared to the proposed device of 41.2 µC. At 1000 ohms the measured values are 30 and 28 µC, respectively. The measured phase charge for the proposed device is equivalent to that of the Odstock device. The modification does not raise any safety or effectiveness.

Maximum RMS Current Density

The measured Maximum RMS Current Density of the proposed device is 1.80 mA rms/cm², compared to the Odstock and Bioness devices both with 0.82 mA rms/cm2 and the parent device at 1.1 mA rms/cm2. There are no specific requirements for the Maximum RMS Current Density in IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators". Paragraph 51.104 of IEC 60601-2-10 specifies a maximum rms output current level of 50 mA. Using this 50 mA rms maximum current the

{12}------------------------------------------------

maximum allowable current density for the proposed device is 6.32 mA rms/cm², as compared to the measured value of 1.80 mA rms/cm2. In addition, the Maximum RMS Current Density is directly related to the Maximum Average Power Density discussed in the next paragraph. Using the 0.25 Watts/cm2 limit of the FDA document "Guidance Document for Powered Muscle Stimulator 510(k)s" June 9, 1999 the Maximum RMS Current Density allowable under this limit for the proposed device can be computed as 7.95 mA rms/cm2. The modification does not raise any safety or effectiveness issues since it meets the applicable requirements of IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators." V012 " WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10

Maximum Average Power Density

The Maximum Average Power Density at 500 ohms load for the proposed device is computed to be 0.027 Watts/cm- compared to 0.012 Watts/cm- for the parent device. These levels were computed assuming a square pulse which, as discussed previously, is not representative of the actual pulse shape or pulse energy. For comparison purposes there are no equivalent parameters provided by the competitive devices. Power density levels for the proposed, Odstock, and Bioness devices using measured rms current levels and stated electrode sizes are 0.0128, 0.0848, and 0.0536 Watts/cm2, respectively. The FDA document "Guidance Document for Powered Muscle Stimulator 510(k)s" June 9, 1999, states in Section 3 that the maximum power density should be under 0.25 Watts/cm2. The measured power density of the proposed device is over an order of magnitude under this limit. The modification does not raise any safety or effectiveness issues.

Summary

The proposed WalkAide device meets the applicable clauses of IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators."

These modifications do not raise any safety or effectiveness issues.

7. CONCLUSIONS

{13}------------------------------------------------

The Output Specifications of the proposed device and the parent device are substantially equivalent. The changes to the output voltage and output pulse width are equivalent to the Bioness and Odstock competitive devices and also still meet the applicable clauses of IEC 60601-2-10 "Particular Requirements for the Safety of Nerve and Muscle Stimulators". V012 " WalkAide Performance Test Protocol" tests to the applicable requirements of IEC 60601-2-10. The addition of Ramp Up and Ramp Down is equivalent to the ramping of the Bioness and Odstock devices.

Based on the above information regarding the equivalent intended use and similar technological characteristics, Innovative Neurotronics believes that the proposed WalkAide is substantially equivalent to the parent WalkAide. The modifications do not raise any safety or effectiveness issues and meet the applicable requirements of IEC 60601-2-10 "Particular requirements for the safety of nerve and muscle stimulators." We conclude that, based on the information above and the Comparison chart below, the proposed Innovative Neurotronics WalkAide System (K123972) is substantially equivalent to the parent Innovative Neurotronics WalkAide System (K052329), the Bioness L300 Plus (K103343), and the Odstock Pace (K102115).

{14}------------------------------------------------

Image /page/14/Picture/0 description: The image shows the text "DEPARTMENT OF HEALTH & HUMAN SERVICES" in all caps. The text is in a bold, sans-serif font. The text is centered horizontally and vertically in the image. The background of the image is white.

Public Health Service

Image /page/14/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 seal is a stylized symbol composed of three curved, parallel lines that resemble a human figure.

April 1,2013

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring, MD 20993-0002

Innovative Neurotronics, Inc. c/o Mr. Glen Neally 3600-B North Capital of Texas Highway Suite 150 Austin, Texas 78746-3211

Re: K123972

Trade/Device Name: WalkAide System Regulation Number: 21 CFR 882.5810 Regulation Name: External Functional Neuromuscular Stimulator Regulatory Class: Class II Product Code: GZI Dated: March 13, 3013 Received: March 19, 2013

Dear Mr. Neally:

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 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. The general controls provisions of the Act include requirements for annual registration. Ilisting 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 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 (reporting of medical device-related adverse events) (21 CFR 803); good manufacturing practice requirements as set

{15}------------------------------------------------

Page 2 -- Mr. Glen Neally

forth in the quality systems (OS) 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/ycm115809.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.

Joyce M. Whang

for Victor Krauthamer, Ph.D. Acting Director Division of Neurological and Physical Medicine Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

{16}------------------------------------------------

Indications for Use

510(k) Number :_K123972

Device Name: Innovative Neurotronics, Inc., WalkAide External Functional Neuromuscular Stimulator

Indications for Use:

The Innovative Neurotronics WalkAide External Functional Neuromuscular Stimulator (WalkAide System) is intended to address the lack of ankle dorsiflexion in patients who have sustained damage to upper motor neurons or pathways to the spinal cord. During the swing phase of gait, the WalkAide System electrically stimulates the appropriate muscles that cause ankle dorsiflexion and may thus improve the patient's gait. Medical benefits of Functional Electrical Stimulation (FES) may include prevention of disuse atrophy, increased local blood flow, muscle re-education, and maintained or increased joint range of motion.

Prescription Use X (Part 21 CFR 801 Subpart D) AND/OR

Over-the-Counter Use (21 CFR 807 Subpart C)

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

BrianDPullin-S

Division of Neurological and Physical Medicine Devices 510(k) Number: K123972

Regulation Number and Section

§ 882.5810 External functional neuromuscular stimulator.

(a)
Identification. An external functional neuromuscular stimulator is an electrical stimulator that uses external electrodes for stimulating muscles in the leg and ankle of partially paralyzed patients (e.g., after stroke) to provide flexion of the foot and thus improve the patient's gait.(b)
Classification. Class II (performance standards).