← Product Code [SDO](/submissions/PM/subpart-f%E2%80%94physical-medicine-therapeutic-devices/SDO) · K253638

# xStep (xStep) (K253638)

_Spinex, Inc. · SDO · Apr 20, 2026 · Physical Medicine · SESE_

**Canonical URL:** https://fda.innolitics.com/submissions/PM/subpart-f%E2%80%94physical-medicine-therapeutic-devices/SDO/K253638

## Device Facts

- **Applicant:** Spinex, Inc.
- **Product Code:** [SDO](/submissions/PM/subpart-f%E2%80%94physical-medicine-therapeutic-devices/SDO.md)
- **Decision Date:** Apr 20, 2026
- **Decision:** SESE
- **Submission Type:** Traditional
- **Regulation:** 21 CFR 890.5851
- **Device Class:** Class 2
- **Review Panel:** Physical Medicine

## Regulatory Identification

A transcutaneous electrical spine stimulator to improve skeletal muscle strength and sensation is a device that can be programmed to apply an electrical current via electrodes on a patient's skin over the spine to improve muscle strength and sensation after neurological deficit. The ARCEX System is intended to deliver programmed, transcutaneous electrical spinal cord stimulation in conjunction with functional task practice in the clinic to improve hand sensation and strength in individuals between 18 and 75 years old that present with a chronic, non-progressive neurological deficit resulting from an incomplete spinal cord injury (C2-C8 inclusive).

## Special Controls

In combination with the general controls of the FD&C Act, the transcutaneous electrical spine stimulator to improve skeletal muscle strength and sensation is subject to the following special controls:

- (1) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. The following performance characteristics must be evaluated:
	- (i) Characterization of the electrical stimulation parameters, including the following: waveforms; output modes; maximum output voltage and maximum output current; pulse duration; frequency; net charge per pulse; maximum phase charge, maximum current density, maximum average current, and maximum average power density:
	- Characterization of the impedance monitoring system; and (ii)
	- Characterization of electrode performance, including the electrical performance, (iii) adhesive integrity, shelf life, reusability, and current distribution of the electrode surface area.
- (2) Performance data must demonstrate the electromagnetic compatibility, electrical safety and performance, battery safety, and wireless compatibility of the device.
- Software verification, validation and hazard analysis must be performed. (3)
- (4) The patient-contacting components of the device must be demonstrated to be biocompatible.
- (ર) Labeling must include:
	- Summaries of electrical stimulation parameters; (i)
	- Instructions for user management of the device in the event of adverse effects; (ii)
	- A contraindication for patients with active implantable devices or wearable (iii) defibrillators:
	- (iv) Information on the typical sensations experienced during treatment;
	- Instructions for accurate placement of the device on the patient; and (v)
	- Cleaning instructions. (vi)

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**Source:** [https://fda.innolitics.com/submissions/PM/subpart-f%E2%80%94physical-medicine-therapeutic-devices/SDO/K253638](https://fda.innolitics.com/submissions/PM/subpart-f%E2%80%94physical-medicine-therapeutic-devices/SDO/K253638)

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