Study of Phantom Limb Pain Using Peripheral Nerve and Spinal Cord Stimulation

Not Applicable

• Conditions: Amputation; Phantom Limb Pain; Phantom Pain

• Registration Number: NCT05650931
• Lead Sponsor: Artur Biktimirov

Brief Summary

The purpose of this study is to evaluate the effectiveness of neuromodulation for relief of phantom limb pain (PLP) using peripheral nerve (PNS) and spinal cord (SCS) stimulation with implantable electrodes. The researchers expect that PLP in patients with upper limb amputation will be relieved by peripheral nerve and the spinal cord stimulation. The possibility of finding EEG biomarkers for phantom pain will be explored.

Detailed Description

The purpose of this study is to evaluate the effectiveness of neuromodulation for relief of phantom limb pain (PLP) using peripheral nerve (PNS) and spinal cord stimulation (SCS) with implantable electrodes.

The study is conducted to collect information on the role of non-adaptive neuroplasticity and inhibitory descending antinociceptive influences, which determine the effect of peripheral nerve and spinal cord stimulation with implanted electrodes in patients with phantom limb pain as a result of amputation of the upper limb. Neuromodulation is a potential treatment option for chronic pain that may alter maladaptive neuroplasticity and enhance descending inhibitory pathways.

Study participants will be selected according to the inclusion criteria. Next, multichannel electrodes will be implanted in the region of the target peripheral nerves of the amputated limb and the corresponding segments of the spinal cord. The evaluation of the therapeutic effects of pain syndromes will be carried out in the mode of long-term repetitive nerve stimulation. Postoperative follow-up will be carried out from 2 weeks to 1 month. During the follow-up period, patients will complete scales and questionnaires daily.

The stimulator is turned on the day after surgery to assess pain relief. The patient is explained the rules for using the stimulator. The selection of stimulation parameters is carried out according to the generally accepted methodology (the stimulation zone should overlap the pain zone; stimulation should be in the nature of pleasant vibrations). The patient will be given a test stimulation diary to complete every day (at the end of the day) during the entire stimulation period.

The researchers expect that phantom limb pain in patients undergoing upper limb amputation will be relieved by peripheral nerve stimulation. We will explore the possibility of creating a personal phantom sensitivity map to optimize the stimulation program. We will study improving the quality of life and reducing pain.

Patients will be asked to participate in an experiment using electroencephalography (EEG) starting on the 3rd day after implantation. The purpose of this entry is to investigate the bimarkers of phantom pain. As part of the experimental procedure, we plan to sequentially turn off the stimulator until the patient returns to the preoperative pain state, and also turn on the stimulator with fixation of the moments of pain suppression to the level at the beginning of the experiment. During the entire period, the patient's EEG will be recorded. The researchers expect to see changes in alpha and theta EEG rhythms under these experimental conditions.

Study Timeline

• Study Start: 2021-11-01
• Study First Submitted: 2022-11-19
• Status Verified: 2022-12
• Study First Submitted QC: 2022-12-06
• Last Update Submitted: 2022-12-06
• Study First Posted: 2022-12-14
• Last Update Posted: 2022-12-14
• Primary Completion: 2025-09-01
• Study Completion: 2025-11-01

Recruitment & Eligibility

• Status: ENROLLING_BY_INVITATION
• Sex: All
• Target Recruitment: 10

Inclusion Criteria

• Patients with implanted neuromodulation devices.
• Amputation of the upper limb at the level of the forearm.
• Age ranges from 18 to 65 years old.
• The duration from the moment of amputation is from 6 months.
• The presence of persistent chronic pain syndrome is from 4 to 10 points according to the Visual Analogue Scale
• Absence of pregnancy at the time of implantation, confirmed by a pregnancy test.

Exclusion Criteria

• The presence of severe somatic pathology
• The presence of mental illness
• The presence of a gross orthopedic deformity in the limb above the amputation level.
• The presence of oncology.
• The presence of epilepsy.
• Complications after a traumatic brain injury or stroke.
• Purulent - septic pathology.
• Drug addiction.
• Congenital malformation of the upper limb.
• Any conditions that, according to the researcher, fall under the exclusion criteria.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SEQUENTIAL

Primary Outcome Measures

Name	Time	Method
Determining the effectiveness of phantom pain suppression based on the Test Stimulation Diary	up to 1 month	The patient completes a Test Stimulation Diary at the end of each day, noting the location of phantom pain and the percentage of pain reduction during stimulation.
Change according to the scale of the DN4 Neuropathic Pain Questionnaire	baseline and up to 1 month	The DN4 Neuropathic Pain Questionnaire defines the neuropathic nature of pain with a point of 4 to 10.
Change in relative power of slow frequencies (alpha and theta rhythms) on the EEG with the neurostimulator on/off and eyes open/closed.	up to 1 month	The general analysis pipeline includes the calculation of the normalized power spectral density, after which the average power of the alpha rhythm is divided by the average power of the theta rhythm.
Change according to the scale of the PainDetect questionnaire	up to 1 month	The PainDetect questionnaire reflects all possible parameters of pain and allows us to very clearly track the picture of the pain syndrome in dynamics. The score is made in the range from 0 (best score) to 38 (worst score) points.

Secondary Outcome Measures

Name	Time	Method
Change according to the Trinity Amputation and Prosthetics Research Scale (TAPES-R)	baseline and up to 1 month	TAPES-R reflects 3 aspects of psychosocial adjustment (general adjustment, social adjustment and adjustment to functional limitations) and 2 aspects (aesthetics and functionality) of prosthesis satisfaction. The answers reflect the degree of agreement with the statement indicated in the item of the questionnaire, or the degree of satisfaction, or the degree of limitation. The scores on the items of the individual subscales are summarized.
Change according to the SF-36 scale "Quality of Life Assessment"	baseline and up to 1 month	The SF-36 questionnaire consists of eight scales: physical functioning, role-playing, bodily pain, general health, vitality, social functioning, emotional state, and mental health. Each scale varies between 0 (worst score) and 100 (best score) points.

Trial Locations

Locations (1)

Far Eastern Federal University (FEFU); 🇷🇺 Vladivostok, Primorsky Krai, Russian Federation