Safety and feasibility of transcutaneous spinal cord stimulation using the open-source OpenXstim stimulator in children and adults with neurological conditions

Device/Procedure Transcutaneous spinal cord stimulation (tSCS) will be delivered using the OpenXstim, an open-source, programmable constant-current stimulator. Protocol Details Electrode placement: Two cathode electrodes will be positioned midline over the T11–L1 and L1–L2 vertebral levels. Two large anode electrodes will be placed over the left and right iliac crests. Waveform and stimulation parameters: Monophasic or biphasic constant-current pulses (carrier frequency 5–10 kHz; stimulation frequency 5–40 Hz) will be selected empirically by a licensed physiotherapist or clinician with prior neuromodulation experience. Parameters, including waveform type and stimulation intensity, will be adjusted at each session according to the participant’s real-time response to achieve comfortable stimulation below the motor threshold, typically 10–60 mA and within device safety limits. Session schedule: Sessions will last 30–45 minutes, administered 2–3 times per week for 4–6 consecutive months (approximately 48 sessions). The frequency and timing of sessions are based on participant and clinician availability while maintaining a consistent dose (approximately every other day to every three days). Administration and setting: All sessions will be delivered in a clinical setting (e.g., physiotherapy clinic) that adheres to standard hygiene and safety protocols. A licensed physiotherapist or clinician experienced in neuromodulation will conduct all interventions. Ramp-up and ramp-down: Stimulation current will be gradually increased over approximately 10 seconds to the target level at the start of each session and decreased over a similar period at the end, following established protocols in the literature and prior studies. Safety and monitoring: Participant comfort and skin integrity will be checked continuously during stimulation. Blood pressure, blood oxygenation, and other routine safety measures will be recorded. Adherence and fidelity: Attendance and stimulation parameters will be documented in a confidential logbook for each session to monitor adherence and allow analysis of session completion and protocol fidelity.