(269 days)
The Synchrony (20-3000) is an electrical stimulation device indicated for the following uses:
Functional Electrical Stimulation (FES).
- Improvement of hand function and active range of motion in patients with hemiplegia due to stroke or upper limb paralysis due to C5 spinal cord injury.
NeuroMuscular Electrical Stimulation (NMES).
- Maintenance and/or increase of hand range of motion.
- Prevention and/or retardation of disuse atrophy.
- Increase in local blood circulation.
- Reduction of muscle spasm.
- Re-education of muscles.
The Synchrony (20-3000) system is a functional electrical stimulation (FES) device and a powered muscle stimulator. It is specifically designed to enhance hand functionality in patients with arm paresis through a range of customizable therapies. The system integrates five major components: the Stimulator, Sensor, Patient Interface (electrodes), Motor Point Probe, and Clinician App. The therapies are directed and programmed by a clinician through an iOS based application and then the patient may apply the therapy at their home with the Stimulator and Sensor.
The Synchrony system supports three primary therapeutic modes: Contralaterally Controlled Electrical Stimulation (CCFES), cyclical Neuromuscular Electrical Stimulation (CNMES), and Functional Task Practice (FTP). The CCFES mode uses sensor data from the patient's unimpaired side to control the timing, intensity, and movement of the paretic hand/arm, synchronizing stimulation with natural motor patterns. The cyclical NMES mode delivers repetitive stimulation to targeted muscles, aiding in muscle re-training, as described in the systematic review of research studies using cyclic NMES. The FTP mode allows for direct control of hand movements during task-oriented exercises, using real-time sensor feedback and stimulator output.
Stimulation is delivered through up to four electrodes placed on identified motor points, using symmetric balanced biphasic pulses. The system offers preset stimulation amplitudes of 20mA, 40mA, and 60mA, with a pulse width adjustable between 1-250 µsec, providing high precision with 1 µsec resolution. The device's enclosure is constructed from biocompatible ABS Cycoloy, ensuring durability and patient safety, and is rated IP22 for ingress protection.
The stimulator can operate independently or in conjunction with the Synchrony Sensor, depending on the therapy mode selected. The Sensor, which communicates wirelessly with the Stimulator via Bluetooth Low Energy (BLE), uses a Class I laser that is compliant with 21 CFR 1040.10 and 21 CFR 1040.11 to measure hand opening and closure distances, enabling accurate therapeutic adjustments. Both the Stimulator and Sensor are wirelessly charged using an FCC Part 15 compliant charging pad, enhancing ease of use and handling.
The Synchrony system is engineered for ease of use with user-friendly control interfaces for both patients and clinicians. It incorporates a range of safety mechanisms to ensure effective and safe operation, making it a versatile and reliable tool for improving hand functionality through personalized therapeutic interventions.
The provided FDA 510(k) clearance letter for the Synchrony (20-3000) device does not contain information about acceptance criteria or a specific study proving the device meets those criteria.
The letter primarily focuses on establishing substantial equivalence to predicate devices, referencing adherence to recognized standards, and outlining performance differences between the new device and the predicates without providing specific acceptance criteria or study details.
However, based on the information provided, we can infer some details and highlight the missing information:
Key Takeaways from the document relevant to performance and safety:
- Substantial Equivalence: The primary method for demonstrating safety and effectiveness is through substantial equivalence to predicate devices (K123636 and K960457).
- Standards Compliance: The device claims compliance with numerous IEC, ISO, ASTM, and ANSI standards related to safety, essential performance, usability, electromagnetic compatibility, software lifecycle, risk management, biological evaluation, laser safety, battery testing, shipping, cleaning processes, wireless coexistence, and cybersecurity. These standards inherently contain their own acceptance criteria that the device must meet.
- Performance Differences: The comparison tables highlight differences in technical characteristics and output specifications. The rationale for these differences consistently asserts "No impact on safety and effectiveness."
- Clinical Data: The document explicitly states: "No clinical data were reviewed in this submission in support of the subject device." This is a crucial piece of information indicating that clinical trials were not part of this 510(k) submission for performance validation against specific clinical outcomes or acceptance criteria.
Inferred and Missing Information:
Since dedicated acceptance criteria and a study proving the device meets them are not explicitly detailed in the provided text, the table below will reflect what is implied by the substantial equivalence and standards compliance, and explicitly state where information is missing.
1. A table of acceptance criteria and the reported device performance
| Acceptance Criteria (Inferred from Standards & Equivalence) | Reported Device Performance |
|---|---|
| Safety: | |
| IEC 60601-1 Basic Safety & Essential Performance Compliant | Compliant |
| IEC 60601-1-2 Electromagnetic Disturbances Compliant | Compliant |
| IEC 60601-1-6 Usability Compliant | Compliant |
| IEC 60601-1-11 Home Healthcare Environment Compliant | Compliant |
| IEC 60601-2-10 Nerve and Muscle Stimulators Compliant | Compliant |
| IEC 60825-1 Safety of Laser Products (Class I laser) Compliant | Compliant |
| ISO 10993-1 Biological Evaluation Compliant | Compliant |
| ISO 10993-5 Cytotoxicity Compliant | Compliant |
| ISO 10993-10 Sensitization Compliant | Compliant |
| ISO 10993-23 Irritation Compliant | Compliant |
| Patient Leakage Current below 100 microamperes (normal) & 500 microamperes (single fault) | Within acceptable limits (Implied by "No impact on Safety and Effectiveness" and compliance with IEC 60601-1) |
| Max Current Density 2x2" electrodes: 0.34 mA/cm²2x4" electrodes: 0.17 mA/cm²MPP: 1.33 mA/cm² (All comply with |
§ 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).