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The TWIST and TWIST R are add-on drive accessories for wheelchairs.

The TWIST and TWIST R devices are intended to provide auxiliary power to manual wheelchairs to reduce the pushing power needed by their users.

TWIST and TWIST R devices are designed to provide support to active wheelchair users who are physically and mentally able to safely control a manual wheelchair in typical situations, including inclines, even manually.

The device is an add on accessory for manual wheelchairs.

1. TWIST

TWIST device is meant to be added to the wheelchair in 5 different combinations of position and control:

1. Front mounted without handlebar, driven by the wheelchair occupant
2. Front mounted without handlebar, driven by the attendant
3. Front mounted position with handlebar, driven by the wheelchair occupant
4. Rear mounted without handlebar, driven by the wheelchair occupant
5. Rear mounted without handlebar, driven by the attendant

Coupling the TWIST device in front position to the wheelchair raises the front castors off the ground. The single wheel of the "traction unit" is then used for steering.

2. VARIATION TWIST R

VARIATION TWIST R device is meant to be added to the wheelchair in 1 only position (rear) and 2 ways of control

1. Rear mounted without handlebar, driven by the wheelchair occupant
2. Rear mounted without handlebar, driven by the attendant

The provided FDA 510(k) clearance letter pertains to a powered wheelchair accessory (Klaxon TWIST/TWIST R), which is a physical device, not an AI/software as a medical device (SaMD).

Therefore, many of the requested criteria related to AI/SaMD performance evaluation (such as multi-reader multi-case studies, expert consensus for ground truth establishment, training set details, or standalone algorithm performance) are not applicable to this submission.

The acceptance criteria and supporting study described in the document relate to the physical and mechanical properties and safety of the device, specifically addressing changes in maximum speed and maximum user weight.

Here's an analysis based on the provided document, addressing the applicable criteria for a physical medical device:

Acceptance Criteria and Device Performance Study for KLAXON (TWIST); KLAXON (TWIST R)

The submission describes changes made to a previously cleared device (K240267) and the non-clinical tests performed to demonstrate that these changes maintain the device's safety and effectiveness.

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the safety and performance requirements outlined in the referenced ISO consensus standards. The "performance" is the demonstration of compliance with these standards.

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

• Sample Size: Not explicitly stated in terms of a "sample size" as one might see for a diagnostic study. For mechanical and performance testing of a physical device, testing typically involves a representative number of units (e.g., a few prototypes or production units) to demonstrate compliance with standards. The document states "Both the TWIST, and variation TWIST R, devices... have been subjected to the same testing requirements." This implies physical testing of the devices.
• Data Provenance: The tests were conducted by the manufacturer, KLAXON-MOBILITY GmbH, in Austria (their listed address). The data is implicitly "prospective" in that it was generated for this specific 510(k) submission to validate the design changes.

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

N/A. For mechanical and physical performance testing of a medical device like a powered wheelchair accessory, "ground truth" is established by the specifications and performance metrics within recognized consensus standards (e.g., ISO 7176 series). There aren't "experts" in the sense of clinicians establishing a diagnostic ground truth, but rather engineers and technicians performing standardized tests.

4. Adjudication Method for the Test Set

N/A. Mechanical and performance tests typically involve objective measurements against predefined criteria/tolerances specified in the standards, rather than subjective interpretation requiring an adjudication process.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, what was the effect size of how much human readers improve with AI vs without AI assistance

N/A. This device is a physical powered wheelchair accessory, not an AI/SaMD diagnostic tool.

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

N/A. This is not an algorithm or software device.

7. The Type of Ground Truth Used

The "ground truth" or "reference standard" is the compliance with recognized international consensus standards for wheelchairs, specifically:

• ISO 7176-1:2014 (Static stability)
• ISO 7176-2:2017 (Dynamic stability)
• ISO 7176-3:2012 (Braking effectiveness)
• ISO 7176-8:2014 (Static, impact, and fatigue strengths)

These standards define the test methodologies and acceptable performance limits.

8. The Sample Size for the Training Set

N/A. There is no "training set" as this is a physical device, not an AI/machine learning model.

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

N/A. Not applicable for a physical device.

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The TWIST and TWIST R are add-on drive accessories for wheelchairs.

The TWIST and TWIST R devices are intended to provide auxiliary power to manual wheelchairs to reduce the pushing power needed by their users.

TWIST and TWIST R devices are designed to provide support to active wheelchair users who are physically and mentally able to safely control a manual wheelchair in typical situations, including inclines, even manually.

The TWIST and TWIST R are add-on drive accessories for wheelchairs. The main parts of the drive unit include a drive wheel with a brushless motor and tire, an Electronic Control Unit (ECU), a removable lithium ion battery pack, an On/Off button and indicators, a carrying and release handle, a battery charger, front and rear lights, and locking pins. The controller includes a wireless interface, On/Off button, battery level LEDs, speed selection lever and brake button, integrated Li-ION battery cell, and a USB-C socket. The handlebar unit includes a wireless interface, On/Off button, battery level LEDs, accelerator, brake levers, integrated Li-ION battery cell, and a USB-C socket.

The provided text focuses on the K240267 510(k) Summary for the Klaxon TWIST and TWIST R add-on drive accessories for wheelchairs. While it details numerous technical specifications and non-clinical testing standards, it does not include acceptance criteria, performance data against those criteria, or information about a study that proves the device meets specific performance targets in the way typically required for AI/ML medical devices.

Instead, the document asserts substantial equivalence to a predicate device (SMOOV O10) based on similar indications for use, intended use, and demonstration of safety and performance through adherence to recognized standards.

Therefore, I cannot populate the table or answer most of the questions using only the provided text as it pertains to AI/ML device performance and acceptance criteria. The device described is a physical powered wheelchair accessory, not an AI/ML diagnostic or prognostic tool.

Here's a breakdown of what can be extracted and why other parts cannot be answered:

1. A table of acceptance criteria and the reported device performance:

This information is not present in the document in the context of acceptance criteria and performance results for an AI/ML device. The document lists numerous technical specifications for the device (e.g., max speed, motor power, battery capacity, weight), and declares compliance with various ISO and other standards (listed in section 4). However, it does not provide specific acceptance criteria (e.g., "The device must achieve an accuracy of X% for Y task") nor reported performance against such criteria for an AI/ML algorithm.

2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective):

This information is not applicable/not provided as the device is a physical powered wheelchair accessory, not an AI/ML device that requires a test set of data for algorithm performance evaluation. The "testing" referred to is non-clinical, related to physical and electrical safety and performance standards of the hardware.

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):

This information is not applicable/not provided for the same reason as point 2.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

This information is not applicable/not provided for the same reason as point 2.

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:

This information is not applicable/not provided as the device is not an AI-assisted diagnostic or prognostic tool used by human readers.

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

This information is not applicable/not provided for the same reason as point 2 and 5.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):

This information is not applicable/not provided for the same reason as point 2. The "ground truth" for this type of device would be mechanical, electrical, and safety standards verified through engineering tests.

8. The sample size for the training set:

This information is not applicable/not provided as the device is a physical product and does not have a "training set" in the context of AI/ML.

9. How the ground truth for the training set was established:

This information is not applicable/not provided for the same reason as point 8.

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