Brief summary: This single-arm, pilot clinical investigation aims to evaluate Mindful SensoriMotor Therapy (MSMT) enhanced with brain modulation as a treatment of pain due to sensorimotor impairment, such as Phantom Limb Pain (PLP). MSMT consists of consciously retraining the motor and sensory networks used by the missing limb via myoelectric pattern recognition and haptic feedback. In this trial, we further enhance the effect of MSMT by brain modulation, transcranial Direct Current Stimulation (tDCS).

People with upper or lower limb disarticulation (amputation at joint level) or nerve injury will participate in this study. It is a single-arm study in which all participants receive the same intervention. Each participant attends a screening visit, up to 5 baseline assessments, 15 interventions, and 3 follow-ups at 1, 3, and 6 months after the last intervention. Brain imaging will be performed pre- and post-treatment.

Inclusion criteria

• The participant has given written informed consent to participate.
• The participant must have chronic neuropathic pain due to sensorimotor impairment (example PLP).
• At least six months should be passed since the date of injury (acute pain cases should not be included in the study).
• If the participant is under pharmacological treatments, there must be no variations on the medication dosages (steady consumption) for at least 1 month before the screening visit.
• If the participant has previously been treated for neuropathic pain, the last session of that treatment(s) must be at least 3 months before the screening visit.
• Any pain reduction potentially correlated to previous neuropathic pain treatments must have been observed at least 3 months prior to the screening visit, as reported by the participant.
• In the case of having a prosthesis, the participant must be in a stable prosthetic situation (i.e. satisfied with the fitting of the prosthesis or not using a prosthesis).
• Participants must have enough contact surface at the site of the amputation or the injured nerves for the system to work, in the researcher's opinion.
• Participants must be able to perceive the haptic stimulation at the time of the screening visit.
• Participants must not experience painful sensations from haptic stimulation in the stump (i.e. allodynia).
• The participant has a sufficient understanding of both Swedish and English to be able to participate in all study assessments, in the researcher's opinion.
• Participants should not have any other condition or symptoms that can prevent them from participating in the study, in the researcher's opinion.
• No mental inability, reluctance, or language difficulties that result in difficulty understanding the meaning of study participation, in the researcher's opinion.
• The participant should not have any condition associated with the risk of poor protocol compliance, in the researcher's opinion.

Exclusion criteria

- The potential participant will be excluded from the study if the person does not meet at least one of the inclusion criteria.

The study protocol article will be published in a scientific journal.

The study protocol is estimated to be available from November 2021.

open access

However, the person treating the subject is different than the person evaluating the outcomes. This is done to reduce the influence that the care provider might have on the patient reporting positive outcomes.