(29 days)
Spinal Cord Stimulation (SCS)
This system is indicated as the sole mitigating agent, or as an adjunct to other modes of therapy used in a multidisciplinary approach for chronic, intractable pain of the trunk and/or limbs, including unilateral pain. The trial devices are solely used for trial stimulation (no longer than 30 days) to determine efficacy before recommendation for a permanent (long term) device.
Peripheral Nerve Stimulation (PNS)
This system is indicated for pain management in adults who have severe intractable chronic pain of peripheral nerve origin, as the sole mitigating agent, or as an adjunct to other modes of therapy used in a multidisciplinary approach. The system is not intended to treat pain in the craniofacial region.
The trial devices are solely used for trial stimulation (no longer than 30 days) to determine efficacy before recommendation for a permanent (long term) device.
The Nalu Neurostimulation System has been cleared by the FDA for spinal cord stimulation (SCS; K203547) and peripheral nerve stimulation (PNS; K203547) to provide therapeutic relief for chronic, intractable pain of the trunk and/or limbs including unilateral, bilateral nerve pain. The Nalu Neurostimulation therapy utilizes pulsed electrical current to create an energy field that acts on nerves in the spinal cord or peripheral nerve to inhibit the transmission of pain signals to the brain. The Nalu System is implanted only following a successful trial period using the Nalu Neurostimulation trial system.
The Nalu Neurostimulation System consists of five (5) components. The implantable pulse generator (IPG) provides electrical stimulation pulses that are transmitted through the leads, to the desired location, either on the spinal cord or peripheral nerve site. The leads are implantable and designed to deliver electrical pulses to the nerves via an array of four (4) or eight (8) cylindrical electrodes at the distal end. The Trial Therapy Disc or the Therapy Disc houses the battery and electronics for RF power and controls the IPG for therapy delivery via the remote programmer. Implantation of the Nalu IPG and lead components for Spinal Cord Stimulation (SCS) or Peripheral Nerve Stimulation (PNS) is performed via standard surgical tools and techniques, as described in (K203547).
This looks like a 510(k) summary, which typically focuses on demonstrating substantial equivalence to a predicate device rather than presenting a standalone study with specific acceptance criteria and performance metrics for a novel AI device. The document mostly highlights the similarities between the subject device (K221376) and its predicate (K203547).
Based on the provided text, there is no specific AI component or algorithm mentioned, nor are there acceptance criteria or a study described to demonstrate the performance of such a component. The device is a "Nalu Neurostimulation System" which appears to be a hardware device for spinal cord and peripheral nerve stimulation. The changes referenced are related to "Clinician Programmer" software differences for therapy configuration, rather than an AI/ML algorithm that interprets data or makes diagnostic decisions.
Therefore, most of the questions you've asked about acceptance criteria, study details, ground truth, sample sizes, and involvement of experts/AI effectiveness are not applicable to this submission as it doesn't describe an AI/ML device in the context of the typical information provided if it were an AI/ML device.
Here's an attempt to answer your questions based only on the provided text, highlighting where the information is absent because the device does not appear to be an AI/ML product as you seem to be assuming:
1. A table of acceptance criteria and the reported device performance
The document does not explicitly state acceptance criteria in the form of performance metrics (e.g., sensitivity, specificity, AUC) that would be expected for an AI device. Instead, it demonstrates an acceptance of "substantial equivalence" to a predicate device by showing that the technological characteristics and indications for use are the same, and that non-clinical testing confirms safety and performance within established limits.
The tables (Table 1, Table 2, Table 3) provided in the document compare the technological characteristics and therapeutic parameters of the subject device (K221376) and its predicate device (K203547). The "reported device performance" in this context is that these characteristics are "Same as predicate" or that any differences "do not impact the safety and effectiveness of the device."
Table of Acceptance Criteria and Reported Device Performance (as inferred from the document):
| Acceptance Criteria Category | Specific Criteria (Implicitly Met by Predicate Equivalence) | Reported Device Performance (Subject Device K221376) |
|---|---|---|
| Product Code and Class | GZB and GZF, Class II (for SCS and PNS) | Same as predicate (K203547) |
| Regulation Number | 21 CFR 882.5880 (GZB), 21 CFR 882.5870 (GZF) | Same as predicate (K203547) |
| Classification Name | Implanted spinal cord stimulator for pain relief / Implanted peripheral nerve stimulator for pain relief | Same as predicate (K203547) |
| Trade Name | Nalu Neuromodulation System | Same as predicate (K203547) |
| Manufacturer | Nalu Medical, Inc. | Same as predicate (K203547) |
| Intended Use | Stimulation of spinal cord/peripheral nerves for chronic intractable pain | Same as predicate (K203547) |
| Indications for Use | For chronic, intractable pain of the trunk and/or limbs (SCS); For severe intractable chronic pain of peripheral nerve origin (PNS) | Same as predicate (K203547) |
| Clinical Application | Treatment of chronic, intractable pain | Same as predicate (K203547) |
| Prescription Use | Yes | Same as predicate (K203547) |
| Environmental Use | Hospital, Home | Same as predicate (K203547) |
| Intended Clinician | Orthopedic, Neurosurgeon, Anesthesiologist | Same as predicate (K203547) |
| Intended User | Physician, Layperson | Same as predicate (K203547) |
| Implant Site, Leads | Epidural space (SCS) or peripheral nerve areas (PNS) | Same as predicate (K203547) |
| Principle of Operation | Stimulation of spinal cord/peripheral nerve to provide therapeutic relief | Same as predicate (K203547) |
| Mode of Action | RF wireless transmission of energy to deliver stimulation | Same as predicate (K203547) |
| Software Level of Concern | Moderate | Same as predicate (K203547) |
| Therapeutic Electrical Parameters (e.g., Pulse Frequency, Pulse Width, Current, Voltage, Waveform, Charge/Current Density, Net Charge, Power, Pulse Delivery Mode, etc.) | Within specified ranges and identical to predicate | Same as predicate (K203547) |
| Clinician Programmer Software | Software to communicate to Trial Therapy or Therapy Disc; Manual control of current and optional model-based allocation; Safety parameters (charge per phase, charge density, current density) unchanged and within limits. | Differences do not impact safety and effectiveness. New method is an option for faster programming, with patient feedback for effectiveness. |
| Patient Remote Control Software | Software to pair with Trial Therapy or Therapy Disc; SW update to reflect Clinician Programmer changes | No impact on safety or effectiveness (implied by lack of further analysis). |
| Externally Worn Devices Firmware | Firmware update to reflect Clinician Programmer and Remote Control changes | No impact on safety or effectiveness (implied by lack of further analysis). |
| Labeling | Updated to support Clinical Programmer Current Steering options | Differences to labeling do not impact safety and effectiveness. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
Not applicable. The document states, "Nalu Medical determined that bench and non-clinical testing are sufficient to demonstrate that the Nalu Neurostimulation system is as safe and effective as the predicate device." No clinical data (which might involve a test set, sample size, or patient data provenance) was required or submitted for this 510(k) submission, as the device's substantial equivalence was established through non-clinical testing and comparison to the predicate.
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. As no clinical study or test set for an AI/ML algorithm was conducted/submitted, there was no need for experts to establish ground truth. The device is a neurostimulation system, not an AI diagnostic or interpretive tool.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. No test set requiring adjudication was used.
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 device is not an AI-assisted diagnostic or interpretive tool, and no MRMC study was performed.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This device is not an AI algorithm. Its functionality involves hardware for neurostimulation, with software controlling the programming and delivery of stimulation.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
Not applicable. Ground truth for an AI algorithm is not relevant here as the device is not an AI/ML product. The "ground truth" for this submission is implicitly the established safety and effectiveness of the predicate device, validated through non-clinical engineering and performance testing.
8. The sample size for the training set
Not applicable. No AI/ML model training was described or performed for this device.
9. How the ground truth for the training set was established
Not applicable. As no training set for an AI/ML model was used, no ground truth needed to be established for it.
§ 882.5880 Implanted spinal cord stimulator for pain relief.
(a)
Identification. An implanted spinal cord stimulator for pain relief is a device that is used to stimulate electrically a patient's spinal cord to relieve severe intractable pain. The stimulator consists of an implanted receiver with electrodes that are placed on the patient's spinal cord and an external transmitter for transmitting the stimulating pulses across the patient's skin to the implanted receiver.(b)
Classification. Class II (performance standards).