(94 days)
INFREX is indicated to be used for: -
- Symptomatic relief and management of chronic intractable pain.
- Adjunctive treatment in the management of post surgical and post-traumatic, Acute pain condition.
INFREX is a Microcomputer controlled portable two channel electrical stimulator. It allows the treatment specifically tailored to the precise needs of the patient. The unique feature of this unit is that it is supplied with two removable packs of rechargeable batteries and an external charger. The user can put one battery pack in the unit for reatment and another spare pack can be charged outside the unit using the supplied external charger. This system facilitates the user to have charged batteries always available and the treatment can be aak any time. Often the units available in the market consume lot of power and batteries die fast. The Rubber Key Pad operation and LCD protocols makes the use and programming easy and simple. All the parameters remain in the system control except the amplitude & time selectable, which can be set by the patient himself. The ergonomic design makes this unit very comfortable to worn and carry.
The provided document is a 510(k) summary for the INFREX device, a Transcutaneous Electrical Nerve Stimulator (TENS) and Interferential Stimulator. This type of submission focuses on demonstrating substantial equivalence to a legally marketed predicate device rather than presenting a clinical study with detailed acceptance criteria and performance metrics in the way a new, high-risk device might.
Therefore, the document does not contain a traditional "study that proves the device meets the acceptance criteria" in the sense of a clinical trial with statistical endpoints for AI performance. Instead, it relies on demonstrating that the new device has the same intended use and similar technological characteristics as predicate devices, and that any differences do not raise new questions of safety or effectiveness.
However, I can extract information related to the acceptance criteria (defined by the substantial equivalence comparison) and the device's technical specifications as its "reported performance" in a comparative context.
Here's an analysis based on the provided text, addressing your points where data is available:
1. Table of Acceptance Criteria and Reported Device Performance
Since this is a 510(k) for substantial equivalence, "acceptance criteria" are implicitly defined by the technical specifications and performance characteristics of the predicate devices. The new device (INFREX) must demonstrate similar performance or that any differences do not raise new safety/effectiveness concerns.
Here's a comparison of key technical specifications, where INFREX's performance is implicitly "accepted" if it is similar to or an improvement upon the predicate devices, or if the differences are justified as safe and effective.
| Characteristic | Acceptance Criteria (Predicate TENS TS1211) | Acceptance Criteria (Predicate IF-4000) | Reported Device Performance (INFREX) |
|---|---|---|---|
| Power Source | +9 Volts Alkaline Battery or AC Adaptor | +9 Volts Alkaline Battery or AC Adaptor | 1.2 Volts * 4 Ni - Mh battery pack (rechargeable). Safety advantage claimed. |
| Number of outputs | Two | Two | Two |
| Channels | Two | Two | Two |
| Synchronous | Yes | Yes | Yes |
| Max Output Current | 80 mA @ 500 Ohms Load | 32 mA @ 500 Ohms Load | TENS: 60 mA @ 500 Ohms, 24mA @ 2K Ohm, 5.4mA @10K Ohm. |
| IFT: 54 mA @ 500 Ohms, 21mA @2K Ohm, 4.4mA @10K Ohm. (Higher for IFT mode than IF-4000, lower for TENS mode than TENS TS1211) | |||
| Max Output Voltage | 40 V @ 500 Ohms Load | 16 V @ 500 Ohms Load | TENS: 30 V @ 500 Ohms, 48V @ 2K Ohm, 54V @10K Ohm. |
| IFT: 27V @ 500 Ohms Load, 42V @ 2K Ohm, 44V @10K Ohm. (Higher for IFT mode than IF-4000, lower for TENS mode than TENS TS1211 at 500 Ohms and 2K Ohms) | |||
| Channel isolation | Yes, conform to ANSI 3.2.3.2, 1985. | Yes, conform to ANSI 3.2.3.2, 1985. | Yes, conform to ANSI 3.2.3.2, 1985. |
| Waveform | Asymmetrical Biphasic Square Wave | Symmetrical Biphasic/Square Wave | Symmetrical Biphasic Square Wave (Matches IF-4000, differs from TENS TS1211) |
| Pulse width | 50 to 300 uS | 125 μS | TENS: 50, 100, 150, 200 and 250 uS selectable. |
| IFT: 125 µS. (TENS range generally within predicate TENS, IFT matches predicate IF-4000) | |||
| Frequency | 2 to 150 Hz | Ch1: 4000 Hz, Ch2: 4080 to 4150 Hz variable beat (1-150Hz sweep selectable) | TENS: 5 and 60 Hz selectable. |
| IFT: Ch1: 4000 Hz, Ch2: 4080 to 4150 Hz. (Fixed beat frequency 80Hz to 150 Hz sweep stated in "Multiwaves" section, not granularly listed in table) (TENS frequency range is narrower than predicate TENS, IFT frequencies are very similar to predicate IF-4000) | |||
| Max. Phase charge | 24.000 µC @ 500 Ohms Load | 4.00 µC @ 500 Ohms Load | TENS: 7.500 µC @ 500 Ohms. |
| IFT: 3.375 µC @ 500 Ohms. (Lower for TENS mode than predicate TENS, similar for IFT mode to predicate IF-4000) | |||
| Current Density (2" Elec) | 0.355 mA / cm2 @ 500 Ohms Load | 1.578 mA / cm2 @ 500 Ohms Load | TENS: 0.089 mA / cm2 @ 500 Ohms Load. |
| IFT: 2.66 mA / cm2 @ 500 Ohms Load. (Lower for TENS, higher for IFT) | |||
| Power Density (2" Elec) | 0.0142 Watt / cm2 @ 500 Ohms Load | 0.02525 Watt / cm2 @ 500 Ohms Load | TENS: 0.0027 Watt / cm2 @ 500 Ohms Load. |
| IFT: 0.0718 Watt / cm2 @ 500 Ohms Load. (Lower for TENS, higher for IFT) | |||
| Microcontroller | TENS TS1211: Yes, IF-4000: No (Analog) | Yes, high-speed for accuracy and precision (stated as an improvement over analog IF-4000). | |
| Safety Circuit | Not explicitly detailed, but assumed per standards | Not explicitly detailed, but assumed per standards | Self-contained safety circuit. Open/short circuit performance confirmed (functions normally after open/short circuited conditions for 15 mins at max settings). |
| Indications for Use | Symptomatic relief and management of chronic intractable pain. Acute pain condition. | Symptomatic relief and management of chronic intractable pain. Acute pain condition. | Symptomatic relief and management of chronic intractable pain. Adjunctive treatment in the management of post surgical and post-traumatic, acute pain condition. (Identical to predicate devices) |
Study Information (Based on 510(k) Submission Type)
This is a Traditional 510(k) submission (K060246) for medical device clearance, not a clinical trial report for an AI algorithm. The "study" here refers to the engineering, design controls, and comparison to predicate devices, rather than a clinical performance study with human subjects validating specific metrics like sensitivity or specificity.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not applicable in the context of this 510(k). The document describes technical specifications and design verification, not a clinical test set from patient data.
- Data Provenance: Not applicable. The data presented is engineering specifications and comparisons to predicate devices, not clinical data sets.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
- Not applicable. This device is an electrical stimulator, not an AI diagnostic tool requiring expert ground truth for interpretation of images or other complex data.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
- Not applicable. No "test set" in the context of expert adjudication is mentioned. The device's technical specifications are verified through engineering tests and comparison to recognized standards (e.g., ANSI 3.2.3.2, 1985).
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. This is not an AI-assisted diagnostic or interpretive device. It is a physical electrical stimulator.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- Not applicable. This is not an AI algorithm. It's a medical device with fixed operational parameters and control by the patient (for amplitude & time) or clinician. The "microcontroller" discussed enhances precision, but it's not an AI performing clinical tasks.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
- The "ground truth" for this submission is adherence to recognized electrical and safety standards (e.g., ANSI 3.2.3.2, 1985 for channel isolation) and demonstration of similar or improved technical performance characteristics compared to legally marketed predicate devices, verifying that the device functions as intended and safely delivers the specified electrical stimulation. This is validated through engineering design and testing, as described implicitly by the "design control activities, verification and validation activities" mentioned in the "Safety" section.
8. The sample size for the training set
- Not applicable. There is no AI model being trained with a dataset.
9. How the ground truth for the training set was established
- Not applicable. There is no AI model being trained with a dataset.
Summary of what the document does describe for acceptance and proof:
Instead of clinical study data for AI, the document focuses on:
- Substantial Equivalence: The primary "acceptance criteria" for a 510(k) is demonstrating that the new device is as safe and effective as a legally marketed predicate device. This is proven by showing:
- Identical Indications for Use: INFREX has the exact same Indications for Use as its predicate devices.
- Similar Technological Characteristics: A detailed comparison of technical specifications (output current, voltage, waveform, pulse width, frequency, etc.) is provided to show that INFREX is technologically similar to the predicate devices.
- Resolution of Differences: Where there are differences (e.g., power source - rechargeable batteries; microcontroller for precision; specific parameter ranges), the submitter argues these differences do not raise new questions of safety or effectiveness, and in some cases, are presented as improvements (e.g., rechargeable batteries for portability, microcontroller for precision over analog).
- Safety and Performance Testing: The document mentions "design control activities, verification and validation activities" and specifically notes open/short circuit performance testing ("This INFREX functions normally after open and short circuited conditions between output jacks, with the device operating for maximum of 15 minutes, in each condition at the maximum available setting of pulse width, pulse rate and pulse amplitude"). This confirms the device's electrical safety and functional integrity under specific fault conditions. Compliance with standards like ANSI 3.2.3.2, 1985 for channel isolation is also stated.
§ 882.5890 Transcutaneous electrical nerve stimulator for pain relief.
(a)
Identification. A transcutaneous electrical nerve stimulator for pain relief is a device used to apply an electrical current to electrodes on a patient's skin to treat pain.(b)
Classification. Class II (performance standards).