(86 days)
The RT300 adult and pediatric versions are intended for general rehabilitation for:
- Relaxation of muscle spasms
- Prevention or retardation of disuse atrophy
- Increasing local blood circulation
- Maintaining or increasing range of motion
The RT300 pediatric version is intended for population ages 4 to 12 years.
The RT300 is a Functional Electrical Stimulation (FES) cycle ergometer which is composed of:
- a motorized leg cycle ergometer (RTI part number SA100047 for adults and SA100044 for children)
- an optional motorized arm crank (RTI part number PP102663)
- an FES controller / stimulator (RTI part number SA100090)
- a leg and optional arm stimulation cable (either bilateral or unilateral) which connects the controller / stimulator to cutaneous electrodes
- cutaneous electrodes (up to 12 electrodes for up to 6 stimulation channels)
- an interface to a remote database for the storage and retrieval of therapy settings and the storage of therapy session logs
- an interface to a pulse oximeter for the display and recording of pulse and SpO2 levels and provision of alarming based on the data
This system allows a person with impaired upper or lower extremity movement to undertake cycle ergometry both actively (utilizing FES evoked upper or lower extremity muscle contractions) and passively (utilizing power developed by the ergometer's motor).
Here's an analysis of the RT300 device's acceptance criteria and the supporting study, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The provided document describes a 510(k) submission, which focuses on demonstrating "substantial equivalence" to a legally marketed predicate device rather than setting or meeting specific quantitative performance acceptance criteria in the same way a de novo device might. Therefore, the "acceptance criteria" here are primarily about demonstrating that the new device (RT300) is just as safe and effective as the predicate device (RESTORATIVE THERAPIES, INC. product: "RT300", K071486).
| Acceptance Criteria Category | Specific Criterion (Implied) | Reported Device Performance (RT300) | Notes |
|---|---|---|---|
| Intended Use Equivalence | The RT300 must have the same intended use as the predicate device. | "The RT300 has the same intended use as the predicate device." | |
| Intended uses for both adult and pediatric versions: Relaxation of muscle spasms, prevention/retardation of disuse atrophy, increasing local blood circulation, maintaining/increasing range of motion. Pediatric version for ages 4-12 years. | This is a core tenet of 510(k) substantial equivalence. The stated intended uses are a direct match to the predicate. | ||
| Output Characteristics Equivalence | The RT300 must have the same output characteristics as the predicate device. | "The RT300 has the same output characteristics as the predicate device." | |
| Specifically, the stimulator delivers 0-140mA charge-balanced stimulation, identical to the predicate. | This refers to the physiological output of the device (electrical stimulation parameters). Ensuring these are identical supports the claim of equivalence in therapeutic effect. | ||
| Technological Similarities/Differences | Any technological differences between the RT300 and the predicate device must not raise new questions of safety and effectiveness. | "The different technological characteristics do not raise new questions of safety and effectiveness." | |
| Demonstrated that features like motorized arm crank (with FES vs. without FES in predicate) and bilateral/unilateral upper extremity stimulation were validated. (See study details below). | |||
| Other components (power, controller, flywheel, seating, database interface, pulse oximeter interface) are identical or similar. | This is a qualitative assessment. The submission argues that new features (like upper extremity FES) or minor differences (like specific motor design for flywheel effect) do not introduce new risks or reduce effectiveness. | ||
| Safety and Effectiveness | The RT300 must be as safe and effective as the predicate device. | "In conclusion, RTI's clinical and non clinical testing has demonstrated that the RT300 is as safe and effective as the predicate device." | |
| Specifically, "The safety and effectiveness of providing both bilateral and unilateral electrical stimulation to the upper extremities has been demonstrated during validation testing." | This is the overarching conclusion drawn from the entire submission leveraging the comparison to the predicate. The "validation testing" refers to the small clinical study for upper extremity stimulation. |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size: The clinical test for upper extremity stimulation involved five able-bodied individuals.
- Data Provenance: The text does not specify the country of origin. It indicates this was a prospective validation testing, performed specifically for this submission.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
The document does not provide information regarding the number or qualifications of experts used to establish ground truth for this validation. Given the nature of validating electrical stimulation (e.g., confirming muscle contraction, user comfort, absence of adverse events), it is likely that physical therapists, physicians, or the device developers themselves observed and evaluated the outcomes. However, this is not explicitly stated.
4. Adjudication Method for the Test Set
The document does not specify an adjudication method. With a small sample size of five individuals for a validation of upper extremity stimulation, it's possible that a single observer or development team assessed the outcomes without a formal adjudication process.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance
- No MRMC comparative effectiveness study was done.
- This device is not an AI-assisted diagnostic or interpretative device. It is a physical therapy device (Functional Electrical Stimulation cycle ergometer). Therefore, the concept of "human readers improving with AI vs. without AI assistance" is not applicable to the RT300. The study focused on demonstrating the physical effectiveness and safety of stimulating upper extremity muscles.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- A standalone performance assessment was conducted for certain aspects. The "output characteristic measurement of new device" performed without human interaction, to confirm technical specifications like current output, falls under a standalone assessment of the device's electrical performance.
- However, the clinical testing itself (upper extremity stimulation) inherently involved human interaction (the five able-bodied individuals and those observing/administering the stimulation). Since the device's function is to interact with a human body for therapeutic effect, a purely "algorithm-only" performance for its intended use isn't directly applicable beyond its electrical output.
7. The Type of Ground Truth Used
- For the upper extremity stimulation validation, the ground truth was likely based on direct observation of physiological response (e.g., muscle contraction, range of motion changes, absence of pain/adverse effects) in the able-bodied individuals. It's an assessment of the physical efficacy and safety of the stimulation, not a diagnostic accuracy against a histological or imaging ground truth.
8. The Sample Size for the Training Set
- The document does not refer to a training set in the context of an algorithm or AI development. The RT300 is an FES device, not a machine learning-based system that requires a training set for model development. The "training" here refers more to product development, testing, and validation against design specifications and predicate performance.
9. How the Ground Truth for the Training Set Was Established
- As there is no mention of a "training set" in the context of AI or algorithm development, this question is not applicable. The device's electrical and mechanical design was likely developed based on established physiological principles of FES and engineering standards, not through a data-driven training process.
§ 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).