(116 days)
The Modular Power Positioning system is appropriate for use by any individual who drives a power wheelchair and who desires or requires a change of position without having to utilize the services of an attendant. Needs for position changes include:
- All positioning benefits associated with the tilt/recline product:
Comfort: As with any individual, able-bodied or disabled, changes in position are necessary to maintain a state of comfort.
Positioning: Individuals without adequate upper-body stability can be tilted to allow gravity to hold them in position. Pressure Relief or Reduction: Individuals who wish, from time to time, to redistribute pressure from one area of the body to another, can do so by tilting and/or reclining, By changing the individual's orientation in space, pressures caused by gravity will shift. - Positioning/Versatility: Individuals are able to reach higher elevations in a seated position, increasing their range of motion and accessibility.
Motion Concepts makes no claims as to the therapeutic effectiveness of the products. Our only claims relate to the ability of the products to provide safe and reliable powered repositioning on the equipment onto which they are installed.
The Modular Power Positioning System is a seating system which is added to a power wheelchair base to provide three basic functions, power recline including shear reduction, and power elevate (or lift). Note the Modular power positioning system in itself does not include any wheelchair base components such as wheelchair frame, drive train, drive controls, wheels, brakes, batteries, suspension etc.
The Tilt unit utilizes a center of gravity shift linkage, which causes the seat frame to shift progressively forward throughout the range of tilt. This enhances the stability since the center of gravity is kept substantially in place while the user is tilting. The Tilt unit may be one of two similarly designed systems, one designed for 50° tilt, and one for 45° tilt which is integrated with the 12 inch linkage style lift.
The Recline function causes the position of the occupant's back to change by changing the position of the backrest with respect to the seat pan. The Shear Reduction works in conjunction with Recline to reduce the shear movement between the user and the backrest. The latter is accomplished by using a linkage that slides the backrest down on the back posts as the back reclines. The range of Recline is 90° to 168°.
The Elevating seat (or Lift) module allows the user to elevate the entire seat by up to 12 inches. It consists of a standard linkage style mechanism.
The maximum occupant weight for the system is up to 300 lb depending on the features of the wheelchair base and system modules selected. The Modular Power Positioning System is assembled using primarily laser-cut steel tube, machined aluminum, and mounting hardware.
The various power positioning modules may be activated via two options: using switches or through the wheelchair manufacturer's controller. Switches consist of either push button or toggle style.
Safety features include a drive lock-out which prevents the user from driving the power chair while tilted, reclined, or elevated beyond a certain pre-set limit. Electrical components are maximum 24 volts, and include a current limiter in the relay box. Stability of the Modular Power Positioning System was tested on various wheelchairs commonly used for power positioning applications. These tests were conducted to ensure the safety of the power wheelchair was not compromised by the addition of the power positioning system.
The provided document is a 510(k) premarket notification for a medical device called the "Modular Power Positioning System," which is a component added to power wheelchairs. This document focuses on demonstrating substantial equivalence to a predicate device and includes performance data from various types of testing, but it does not describe an AI/ML powered device or a study involving human readers or ground truth established by experts in the context of diagnostic performance. Therefore, many of the requested categories in your prompt are not applicable to the information contained in this document.
However, I can extract the information that is available regarding the device's acceptance criteria and the studies performed.
Here's a breakdown based on the information provided:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state "acceptance criteria" in a quantitative format as would be typical for diagnostic performance (e.g., sensitivity, specificity thresholds). Instead, it lists various tests performed and implies that compliance with relevant standards and successful completion of these tests constitute meeting the acceptance criteria for safety and effectiveness.
| Performance Metric/Test Category | Reported Device Performance |
|---|---|
| Biocompatibility Testing | Performed on all skin contacting surface materials (Meshtex, Startex, Spacetex 4000U™, O-Vinyl, Style 6499 Polyester and Integral Skin foam) per ISO 10993 Part 5: Testing for in vitro cytotoxicity. |
| Electrical Safety and EMC | Complies with RESNA Section 21, Requirements and Test Methods for Electromagnetic Compatibility of Electrically Powered Wheelchairs and Scooters. |
| Software Verification and Validation | Conducted, documentation provided as recommended by FDA's Guidance. Software has a "Moderate level of Concern." |
| Mechanical Testing | Carried out to cover functional verification and device performance, established correct functionality according to relevant ANSI/RESNA standards. |
| Acoustic Testing | Not required to demonstrate device safety and effectiveness. |
| Animal Study | Not required to demonstrate the safety and effectiveness. |
| Clinical Studies | Not required to demonstrate the safety and effectiveness. |
| Stability (Full Drive - FD) | Tested with wheelchair in various positions (elevated, tilted, reclined). |
| Stability (Reduced Drive - RD) | Tested with wheelchair in various positions. |
| Power Consumption | 24 VDC / 4 Amps (improved from predicate device's 8 Amps). |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not specify sample sizes for any of the performance tests. The testing appears to be primarily bench testing (mechanical, electrical, software) and material biocompatibility, rather than human clinical data. The device manufacturer, Motion Concepts, is based in Concord, Ontario, Canada, suggesting the testing was likely conducted in Canada or by labs associated with the manufacturer. These would be considered prospective tests performed on the physical device components.
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 a mechanical/electrical system, not a diagnostic AI/ML system requiring expert interpretation of medical data to establish ground truth.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not Applicable. No human adjudication of results is mentioned or relevant for the types of tests performed.
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-powered diagnostic device, and no MRMC study was conducted.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not Applicable. This device does not have an AI algorithm with standalone performance to evaluate in this context. While it has software, its V&V is focused on functional safety rather than diagnostic accuracy.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for this device's performance would be the physical and electrical properties of the device components and system as measured against engineering specifications and industry standards (e.g., ANSI/RESNA, ISO). For example:
- Biocompatibility: In vitro cytotoxicity results as per ISO 10993.
- Electrical Safety/EMC: Compliance with RESNA Section 21.
- Mechanical Performance: Functionality according to relevant ANSI/RESNA standards (e.g., static stability, dynamic stability, impact, fatigue strengths).
- Software Safety: Verification against documented requirements and risk analysis.
8. The sample size for the training set
Not Applicable. This device uses conventional engineering design, not a machine learning model that requires a training set.
9. How the ground truth for the training set was established
Not Applicable. No training set for an AI model is involved.
§ 890.3860 Powered wheelchair.
(a)
Identification. A powered wheelchair is a battery-operated device with wheels that is intended for medical purposes to provide mobility to persons restricted to a sitting position.(b)
Classification. Class II (performance standards).