The Infinity Plus is a multifunction electrotherapy device with various treatment modes that allow for neuromuscular electrical stimulation (NMES) and interferential current stimulation (IFS).

As a NMES device, the Infinity Plus device is indicated for the following conditions:

Retarding or preventing disuse atrophy .
Maintaining or increasing range of motion .
Re-educating muscles .
Relaxation of muscle spasm .
Increasing local blood circulation .
Prevention of venous thrombosis of the calf muscles immediately after surgery

As an IFS device, the Infinity Plus is indicated for the following conditions:

Symptomatic relief of acute pain .
Symptomatic relief and management of chronic intractable pain .
As an adjunctive treatment for post surgical and post traumatic acute pain .

Device Description

The Empi Infinity Plus Electrotherapy System is a battery-powered/line-powered, multifunction device intended to provide clinicians with the flexibility to prescribe multiple stimulation therapy regimens with the same device. The Infinity Plus offers the following features:

Channel 1 to 4, which are multi-purpose outputs (IF and NMES) .
High Voltage output dedicated to the High Volt stimulation. (This is named CH5 in the Software Requirements Specification and Software Design Specification. It is a separate channel that is simply the output for the high voltage stimulation).
Channel 1, 2, 3 and 4 support stimulation with:
IF: 2 independent IF channels using the channel pairs: Channel 1/2 and Channel 3/4
PM, NMES, Russian: 4 independent PM channels
Serial contractions: 4 dependent channels forming the movement pattern
HV out is dedicated to High Volt stimulation
All channel outputs are electrically separated from each other
Each channel has a dedicated intensity control, with the exception of the HV out. The intensity control of HV is achieved by using the Channel 1 intensity control.
Maximum stimulation of 100 mA for IF, PM, NMES, and Russian; 500 V for High Volt
Timed therapy sessions .
Continuous or cycled stimulation .
Adjustable pulse rates
Adjustable ON and OFF time controls .
Balanced symmetrical biphasic and monophasic high volt waveforms .
Forty-three programs: three conventional interferential, three premodulated interferential, seven High Volt, thirteen NMES, thirteen Russian and four Serial Contraction
Lock option for clinician to control treatment regimens and stimulus intensity
Pause function for patient to pause stimulation. During pause, the timer will not count down if timing has been set up. Upon restart, the device assumes the previous treatment stimulation parameters with stimulus intensity of zero

AI/ML Overview

The provided text describes a 510(k) summary for the Infinity Plus Electrotherapy System. It details the device's intended use, description, and basis for substantial equivalence to predicate devices. However, the document does not contain information regarding
acceptance criteria, specific study designs, sample sizes, expert qualifications, or ground truth methodologies that would typically be found in a clinical study report or a more detailed submission for proving device performance.

Therefore, I cannot provide a complete answer to your request. The information below is limited to what is explicitly stated or can be inferred from the provided 510(k) summary.

Here's what can be extracted based on the document:

1. Table of Acceptance Criteria and Reported Device Performance

The provided 510(k) summary does not explicitly state any quantitative acceptance criteria or provide specific reported device performance metrics like sensitivity, specificity, accuracy, or effect sizes for clinical outcomes. The submission focuses on demonstrating substantial equivalence to predicate devices based on intended use, design, and function.

Acceptance Criteria (Not Explicitly Stated for Performance)	Reported Device Performance (Not Explicitly Stated for Performance)
Implied: Device performs similar to predicate devices for stated indications.	Implied: Device provides NMES and IFS stimulation as intended.
Implied: Device delivers specified electrical parameters (e.g., maximum stimulation current/voltage, adjustable pulse rates/on/off times).	Implied: Device can deliver 100 mA for IF, PM, NMES, Russian, and 500 V for High Volt.
Implied: Device offers the stated features (e.g., 4 channels, specific waveforms, timed therapy, continuous/cycled stimulation, lock option).	Implied: Device possesses the listed features.

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

The 510(k) summary does not describe any specific clinical "test set" or clinical study with a defined sample size to prove performance. The submission relies on a comparison to predicate devices. Therefore, information on data provenance (country of origin, retrospective/prospective) is also not available for such a test set.

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

Since no specific clinical "test set" is described for proving performance, there is no information provided on experts establishing ground truth. This type of information would typically be found in a clinical trial report.

4. Adjudication Method for the Test Set

As no specific clinical "test set" is described, there is no information provided on adjudication methods.

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

The document does not mention a Multi-Reader Multi-Case (MRMC) comparative effectiveness study. The submission focuses on device features and equivalence rather than comparative clinical outcomes with human readers or AI assistance.

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

The Infinity Plus Electrotherapy System is a physical medical device for delivering electrical stimulation, not a software algorithm. Therefore, the concept of "standalone (algorithm only)" performance does not apply to this device. Its performance is inherent in its ability to generate and deliver the intended electrical waveforms, which is typically confirmed through engineering verification and validation, not standalone clinical studies in the AI sense.

7. The Type of Ground Truth Used

Given that no specific studies are detailed to prove performance in the clinical sense, there is no mention of a type of ground truth used (e.g., expert consensus, pathology, outcomes data). The "ground truth" in this context for a 510(k) relating to a physical electrotherapy device would be the device's ability to produce the specified electrical output parameters accurately and safely, as measured by engineering tests.

8. The Sample Size for the Training Set

The provided document does not discuss any "training set." This term is typically associated with machine learning or artificial intelligence models, which the Infinity Plus Electrotherapy System is not.

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

As there is no "training set" mentioned, there is no information on how its ground truth was established.

Summary of what the K041920 document DOES provide:

Basis for Substantial Equivalence: The primary method for clearance for the Infinity Plus Electrotherapy System is demonstrating substantial equivalence to previously cleared predicate devices (Empi 300 PV and Chattanooga Vectra Pro 4 and Pro 2 Models).
Comparison of Features: The document lists features of the Infinity Plus (e.g., four channels, Russian waveform, specific current/voltage limits) and highlights how these are either present in the predicate Empi 300 PV or in the other predicate devices (Chattanooga Vectra Models).
Indications for Use: The Infinity Plus shares the same indications for use as the predicate devices for NMES and IFS.
Regulatory Conclusion: FDA determined the device is substantially equivalent to legally marketed predicate devices, allowing it to proceed to market under general controls.

This 510(k) summary is a regulatory document focused on demonstrating equivalence for market clearance, rather than a detailed report of a clinical performance study with defined acceptance criteria and results.

Summary

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K 041920

510(k) Summary for Infinity Plus Electrotherapy System

1. SPONSOR

Empi 599 Cardigan Road St. Paul, Minnesota 55126-4099

Kathleen Schmitt Contact Person: (651) 415-9000 Telephone:

July 15, 2004 Date Prepared:

2. DEVICE NAME

Proprietary Name:	Infinity Plus Electrotherapy System
Common/Usual Name:	Electrical Muscle and Nerve Stimulator
Classification Names:	Powered Muscle Stimulator, Interferential Current
	Stimulator,

PREDICATE DEVICES 3.

Empi 300 PV	K021100
Chattanooga Vectra Pro 4 and Pro 2 Models	K982324

4. INTENDED USE

The Infinity Plus is a multifunction four-channel, multi-waveform electrotherapy device with various treatment modes that allow for neuromuscular electrical stimulation (NMES) and interferential current stimulation (IFS).

As a NMES device, the Infinity Plus device is indicated for the following conditions:

Retarding or preventing disuse atrophy .
Maintaining or increasing range of motion .
Re-educating muscles .

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Relaxation of muscle spasm .
Increasing local blood circulation .
Prevention of venous thrombosis of the calf muscles immediately after . surgery

As an IFS device, the Infinity Plus is indicated for the following conditions:

Symptomatic relief of acute pain .
Symptomatic relief and management of chronic pain .
Adjunctive treatment for post-surgical and post-trauma acute pain .

DEVICE DESCRIPTION ട.

Channel 1 to 4, which are multi-purpose outputs (IF and NMES) .
High Voltage output dedicated to the High Volt stimulation. (This is . named CH5 in the Software Requirements Specification and Software Design Specification. It is a separate channel that is simply the output for the high voltage stimulation).
- 0 Channel 1, 2, 3 and 4 support stimulation with:
  - IF: 2 independent IF channels using the channel pairs: Channel -1/2 and Channel 3/4
  - PM, NMES, Russian: 4 independent PM channels ﻴ
  - Serial contractions: 4 dependent channels forming the movement pattern
- HV out is dedicated to High Volt stimulation o
- All channel outputs are electrically separated from each other o
- Each channel has a dedicated intensity control, with the exception of o the HV out. The intensity control of HV is achieved by using the Channel 1 intensity control.

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Maximum stimulation of 100 mA for IF, PM, NMES, and Russian; . 500 V for High Volt
Timed therapy sessions .
Continuous or cycled stimulation .
. Adjustable pulse rates
Adjustable ON and OFF time controls .
Balanced symmetrical biphasic and monophasic high volt waveforms .
Forty-three programs: three conventional interferential, three . premodulated interferential, seven High Volt, thirteen NMES, thirteen Russian and four Serial Contraction
Lock option for clinician to control treatment regimens and stimulus . intensity
Pause function for patient to pause stimulation. During pause, the timer . will not count down if timing has been set up. Upon restart, the device assumes the previous treatment stimulation parameters with stimulus intensity of zero

BASIS FOR SUBSTANTIAL EQUIVALENCE 6.

The Empi Infinity Plus is indicated for use in neuromuscular electrical stimulation, as a High Voltage Stimulation device and for premodulated and conventional interferential stimulation. These are the same four indications as for the Empi 300 PV. The Infinity Plus also incorporates an additional Russian waveform used during NMES. The Chattanooga Vectra Models also incorporates a Russian waveform during NMES stimulation. Therefore, the indications for use of the Infinity Plus are the same as those for predicate electrical stimulator devices that have been previously cleared for marketing in the United States.

As the Infinity Plus is an extension of the Empi 300 PV, they are similar in design and function. Both offer multiple treatment programs, and the user can either choose one or more of these options or customize the treatment regimen within the available parameter ranges. The 300 PV has undergone several changes to result in the Infinity Plus as follows: it is now a four-channel system; it incorporates a Russian Waveform for NMES, and is not indicated for FES or TENS. However, the four channel and the Russian Waveform features are available on the other predicate devices (Vectra Pro Models).

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JAN 2 1 2005

Empi C/O Mary McNamara-Cullinane, RAC Staff Consultant Medical Device Consultants, Inc. 49 Plain Street North Attleboro, Massachusetts 02760

Re: K041920

Trade/Device Name: Empi Infinity Plus Electrotherapy System Regulation Number: 21 CFR 890.5850 Regulation Name: Powered Muscle Stimulator Regulatory Class: Class II Product Code: IPF Dated: December 15, 2004 Received: December 16, 2004

Dear Ms. McNamara-Cullinane:

We have reviewed your Section 510(k) premarket notification of intent to market the device w on to re a revea 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 ass builed in 28, 1976, the enactment date of the Medical Device Amendments, or to devices that provisions of the J = 0 ; 0 ; 0 ; 0 ; 0 ; 0 ; 0 ; 1 = 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 nrovisions of the Act include requirements for annual registration, listing of devices, good proviews ing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may 11 your de to such additional controls. Existing major regulations affecting your device can be found be sablet to fact and 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); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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This letter will allow you to begin marketing your device as described in your Section 510(k) I his letter will anow you to begin manieting your and equivalence of your device to a legally prematket notification. The I Driving of basification 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), please If you desire specific advice for your as 10 m . Also, please note the regulation entitled, Colliact the Office of Comphance as (210) = estimal (21CFR Part 807.97). You may obtain other " Misoranding by recreace to premainer he Act from the Division of Small Manufacturers, general information on your responsiblements and 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,
Mark M. Willman

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

Enclosure

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Indications for Use

510(k) Number (if known):

Device Name: Infinity Plus Electrotherapy System

Indications for Use:

The Infinity Plus is a multifunction electrotherapy device with various treatment modes that The Infinity Plus is a multifuliciton electrical reply conventional interferential,
allow for neuromuscular electrical stimulation/River (TES) anow for nourseed interferential current stimulation (IFS).

As a NMES device, the Infinity Plus device is indicated for the following conditions:

Retarding or preventing disuse atrophy .
Maintaining or increasing range of motion .
Re-educating muscles .
Relaxation of muscle spasm .
Increasing local blood circulation .
mercusing
Prevention of venous thrombosis of the calf muscles immediately after surgery e

As an IFS device, the Infinity Plus is indicated for the following conditions:

Symptomatic relief of acute pain .
Symptomatic relief and management of chronic intractable pain .
As an adjunctive treatment for post surgical and post traumatic acute pain .

Over-the-Counter Use AND/OR Prescription Use __ x (21 CFR 807 Subpart C) (Part 21 CFR 801 Subpart D)

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Mark A. Mellemson

Division of General, Restorative. and Neurological 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).