(89 days)
TENS: The device is intended for the temporary relief of pain associated with sore and aching muscles in the lower back, upper extremities (arms) and lower extremities (legs) due to strain from exercise and/or normal household and work activities.
NMS: The device is intended to stimulate healthy muscles in order to improve and facilitate muscle performance.
The Applicant device, XiniWave II Model ECS322P, is a precision Class II device housed in a sturdy lightweight cabinet. The keypad controls and the circuit for the Applicant device are identical to the Predicate. For a maturing user constituency, the cabinet of the Applicant device is larger than the Predicate with a bigger white paper Liquid Crystal Display (LCD), yet the weight of the device is virtually equivalent. The Applicant device is powered by 3 x 1.5V AAA alkaline batteries. The Applicant device offers the user a choice of eight (8) pre-set Transcutaneous Electro Neuro Stimulation (TENS) programs for the temporary relief of pain (80 mA Max.) and one pre-set Neuro-Muscular Electrical Stimulation (NMES) program for muscle conditioning (90 mA Max.). In the NMES mode of operation the user is able to select work/rest stimulation with pulse rates between 2-100Hz and pulse widths between 50-450uS rate may be selected. The mode of action for the Applicant device in TENS or NMES mode is identical to the mode of action to the Predicate.
The Applicant device is supplied with skin electrodes (electrode surface minimum of 25cm -), to stimulate the patient. The skin electrodes (extant for the industry) are the same ones as supplied with the Predicate and delineated in the User's Manual. The Applicant device control unit connects directly to the skin electrode by cable and plug (extant for the industry).
Sold as a kit, the XiniWave II Model ECS322P kit consists of:
One (1) Battery Powered Stimulator (Control Unit)
One (1) set of Four (4) skin electrodes
Three (3x1.5V) AAA Batteries
One (1) User's Manual
One (1) case
This document is a 510(k) premarket notification for the XiniWave II Model ECS322P, a powered muscle stimulator for both TENS and NMES applications. It claims substantial equivalence to a predicate device, XiniWave Model XW-18 (K100441). The document primarily focuses on demonstrating that the new device is as safe and effective as the predicate despite some modifications.
Here's an analysis of the provided text with respect to acceptance criteria and supporting studies:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state formal "acceptance criteria" in the sense of predefined numerical performance targets for a clinical study. Instead, the performance evaluation is based on demonstrating substantial equivalence to a predicate device. The "reported device performance" is a comparison of output parameters between the applicant device and the predicate.
Below is a table summarizing the key device characteristics and their comparison, which effectively serves as the "performance" data used to support substantial equivalence.
| Characteristic | Predicate Device (XiniWave, Model XW-18) Performance | Applicant Device (XiniWave II, Model ECS322P) Performance | Acceptance Criteria (Implied by Substantial Equivalence) |
|---|---|---|---|
| Indications for Use | Temporarily relieves pain (TENS) and stimulates healthy muscles (NMS). | Temporarily relieves pain (TENS) and stimulates healthy muscles (NMS). | Unchanged from Predicate. |
| Technology | Identical fundamental scientific technology. | Identical fundamental scientific technology. | Unchanged from Predicate. |
| Max. Output Current (peak @ 500 Ohms): | 80mA +/- 8% | TENS: 80mA +/- 8%; NMES: 90mA +/- 8% | Within extant mode of clinical effectiveness and cleared devices. |
| Max. Output Current (peak @ 2K Ohms): | 50mA +/- 10% | 50mA +/- 10% | Similar to Predicate. |
| Max. Output Current (peak @ 10K Ohms): | 19mA +/- 10% (shuts off) | 19mA +/- 10% (shuts off) | Similar to Predicate. |
| Pulse Width (μS) | 175 μS – 250 μS (program dependent) | 50 μS – 250 μS (program dependent) | Within extant mode of clinical effectiveness. |
| Frequency (Hz) | 12 Hz - 150Hz (program dependent) | 2 Hz - 100Hz (program dependent) | Within extant mode of clinical effectiveness. |
| Net Charge @ 500 ohms (μC per pulse) | Zero (Asymmetrical DC zero, transformer output) | Zero (Symmetrical DC zero, transformer output) | Similar to Predicate. |
| Max. (Peak) Phase Charge (μC) at 500 ohms | 20 μC (80mA x 250μS) | 40 μC (90mA x 450 μS) | Within extant mode of clinical effectiveness. |
| Max. Current Density (mA/cm²) @ 2 X 2 | 3.2 mA/cm² (Surface = 25 cm²) | 4.3 mA/cm² (Surface = 25 cm²) | Within extant mode of clinical effectiveness. |
| Max. Power Density (W/cm²) @ 500 ohms | 3.8mW/cm² | 7.7 mW/cm² | Within extant mode of clinical effectiveness. |
| Ergonomics (LCD Size) | 35 X 17 mm | 45 X 35 mm | Not explicitly an "acceptance criterion" for safety/effectiveness, but a noted change. |
| Ergonomics (Weight) | 0.09 kg (without battery) / 0.1 kg (with battery) | 0.12 kg (without battery) / 0.16 kg (with battery) | Not explicitly an "acceptance criterion." |
| Software (Programs) | TENS: 7 pre-set; NMES: 6 pre-set | TENS: 8 pre-set; NMES: 1 (user selectable work/rest) | Programs are "Substantially Equivalent" to Predicate. |
| Manual Languages | English | English & Spanish | Not an "acceptance criterion" for device performance, but for labeling compliance. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not describe any "test set" in the context of a clinical study with human subjects or a formal algorithm evaluation. The performance comparison is based on comparing the technical specifications and output parameters of the new device against its predicate. This is a technical, engineering-based comparison rather than a clinical one involving patient data.
- Sample Size for Test Set: Not applicable, no human test set or algorithm evaluation based on data is described.
- Data Provenance: Not applicable, no clinical data is presented. The information is derived from technical specifications and design.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of those Experts
Not applicable. No "ground truth" establishment by experts for a test set is described, as the evaluation is based on technical specifications comparison rather than interpretation of data by experts.
4. Adjudication Method for the Test Set
Not applicable. No test set or adjudication process is described.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done
No. The document does not describe an MRMC comparative effectiveness study, nor any clinical study involving human readers or AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Not applicable. This device is a hardware product, a powered muscle stimulator. It does not involve an "algorithm" in the context of image analysis, diagnostics, or other applications where standalone algorithm performance would be relevant. While it has embedded "programs," these control electrical stimulation output, not information processing or interpretation for which a standalone AI performance would be assessed.
7. The Type of Ground Truth Used
Not applicable. No clinical ground truth (e.g., pathology, outcomes data, expert consensus) is used, as the evaluation is based on engineering and performance specifications.
8. The Sample Size for the Training Set
Not applicable. No "training set" is mentioned or implied, as this is a hardware device with pre-programmed functions, not a machine learning model that requires training data.
9. How the Ground Truth for the Training Set was Established
Not applicable. As there is no training set, there is no ground truth for it.
Summary of the Study:
The "study" described in this 510(k) submission is not a clinical trial or an AI/algorithm validation study. It is a technical and regulatory comparison designed to demonstrate "substantial equivalence" of the XiniWave II Model ECS322P to its predicate device, XiniWave Model XW-18.
The applicant asserts that despite some modifications (battery type, LCD size, physical dimensions, channel connector location, software program specifics, manual languages), the fundamental scientific technology and the intended use remain unchanged. The core of the evidence lies in comparing output parameters (current, pulse width, frequency, charge, power density) to show that the new device's outputs remain within clinically effective ranges and are comparable to or within acceptable variations of the predicate, and thus do not raise new questions of safety or effectiveness. The risk assessment mentioned indicates that product modifications are as safe and effective as the predicate.
§ 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).