(227 days)
The indications for the Limfa Therapy System are to temporarily increase blood circulation in healthy leg muscles and to stimulate healthy muscles in order to improve and facilitate muscle performance.
The Limfa® Therapy System is a medical device, intended for stimulation with extremely low frequencies (ELF), pulsed, and low frequency (ELF 3-300 Hz) magnetic fields, which generates pulsed, bipolar and variable electromagnetic fields, at very low and variable intensity and frequency using complex waveforms (sinusoidal, triangular and rectangular), thus obtaining multiple signals within a frequency spectrum composed of base waves from 2 to 80 Hz plus the harmonics that are produced by the hardware component.
The manufacturer presets base wave frequencies and the harmonics are generated by the DM hardware. The therapy is based on the generation of a pulsed magnetic field with a very low and variable frequency and variable intensity.
The provided FDA 510(k) clearance letter and summary for the Limfa Therapy System (K243165) do not describe a study involving "acceptance criteria and the study that proves the device meets the acceptance criteria" in the context of an AI/ML-driven medical device performance study, which is implied by the detailed questions about sample sizes, expert ground truth, MRMC studies, and training sets.
Instead, this submission focuses on demonstrating substantial equivalence to predicate devices (Bemer Classic Set, K151834 and K210174) based on:
- Indications for Use: Identical.
- Technological Characteristics: Similar primary mode of action (non-invasive tissue stimulation via magnetic field induction), comparable frequency and intensity ranges (ELF PEMF), and compliance with the same safety standards. Differences in waveform shape, pulse duration, and treatment timing are argued to be equivalent without raising new safety or effectiveness concerns.
- Safety and Performance Testing: Compliance with relevant electrical safety (IEC 60601-1, -1-2, -1-6, -1-11), software (EN 62304, EN 62366), quality/risk management (EN ISO 14971), and labeling standards (EN ISO 15223-1, IEC TR 60601-4-2).
The document explicitly states:
- "No animal testing of the subject device was necessary. The performance tests are sufficient."
- "No clinical testing of the subject device was necessary. The performance tests are sufficient."
This type of 510(k) submission, common for devices deemed substantially equivalent to existing, cleared devices, generally does not require new de novo clinical studies demonstrating effectiveness, especially if the device operates on the same principles and within similar parameters as its predicates. The "performance tests" mentioned refer to engineering and electrical safety testing, not clinical performance studies with patient outcomes or expert reviews.
Therefore, I cannot extract the information requested about acceptance criteria, test set details, expert ground truth, MRMC studies, standalone performance, or training set specifics from this document because such studies were not required or performed for this specific 510(k) clearance. The device is cleared based on its substantial equivalence to previously cleared devices through technical comparisons and compliance with relevant safety and performance standards.
§ 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).