Surface Electrical Stimulation for Treatment of Phantom Limb Pain — EPIONE  

Phantom Limb Pain Clinical Trial

Official title: Natural Sensory Feedback for Phantom Limb Modulation and Therapy

Status Active, not recruiting

Clinical Trial Summary

Phantom limb pain (PLP) is a frequent consequence of amputation, and it is notoriously difficult to treat. Amputation usually follows traumatic injuries or surgery following vascular diseases, diabetes, osteomyelitis or tumours in cases where the loss of the limb is required for the survival of the patient. The loss of a limb or other body parts is usually followed by the sensation that the lost body part is still present and can be felt. These phenomena are called, respectively, phantom awareness and phantom sensation. In 50-80% of amputees neuropathic pain develops in the lost limb also referred to as phantom limb pain (PLP). PLP can be related to a certain position or movement of the phantom limb, and might be elicited or worsened by a range of physical factors (e.g. changes in the weather or pressure on the residual limb) and psychological factors (e.g. emotional stress). It is well known that most treatments available for PLP today, such as pharmacological, surgical, anaesthetic, psychological and other, are ineffective.

Today it is believed that phantom limb pain may be related to changes in the cortex of the brain. There is evidence that these changes may be modulated - or even reversed - by providing sensory input to the stump or amputation zone. For example, cortical reorganization and alleviation of phantom limb pain has been observed in amputees following intense use of a hand prosthesis. However, there is no consistent knowledge on which type of peripheral sensory feedback may be effective in affecting the cortical plasticity or on how to best apply the sensory feedback.

The aim of the proposed research is to create natural, meaningful sensations through providing non-invasive sensory feedback (i.e. surface electrical stimulation) and the effectiveness to alleviate phantom limb pain and restore the cortical neuroplastic changes.

Clinical Trial Description

Purpose of the Study. Up to 50-80 % of persons with amputations experience pain in the part of the body that is missing. This phenomenon is called phantom limb pain (PLP). It is not clear today why phantom limb pain occurs, and since the pain can be difficult to treat, it can affect the quality of life. Other scientific studies have shown that the use of electrical stimulation applied through surface electrodes can assist to decrease or alleviate the phantom limb pain. The aim of this study is to investigate if daily electrical stimulation for a period of 30 days can decrease or alleviate PLP.

Methods: This study is conducted in the following phases:

1. Pre-screening

2. Baseline

3. Entry

4. Pre-Therapy

5. Therapy

6. Outcome

7. Follow-up

Procedures during phases 1 to 7 are standardized across international EPIONE partner (which carry out different interventions, but similar assessments), to enable comparison between treatment modalities.

During the different phases of the study a collection of assessment methods are conducted to monitor the effect of stimulation therapy on the amputee's level of perceived PLP and cortical organization. In addition, the psychological state of the subject, the strength and type of the non-painful phantom limb sensations are also assessed to provide a more detailed view on the possible effects of the stimulation therapy.

The experiment will be conducted as a series of case studies where the effect of the stimulation therapy in a subject is compared with the PLP sensations the same subjects perceived before initiating the therapy. Therefore, only amputees who are in a stable state (e.g.,not newly amputated subjects) are included in the study.

No placebo or blinding is performed as the amputee can feel the stimulation and also has to be mentally actively involved in performing "phantom limb movements" when receiving stimulation therapy.

Phases 1-7 for each subject (week -3 to week 12, week = 0 is pre-therapy) are performed according to the experiment protocol defined in collaboration with international partners.

Phase 1: Pre-screening. The pre-screen phase aims to assess the candidate subject for degree and duration of pain, intelligence and psychological state to test these measures against the inclusion criteria. The assessment protocol is administered once per subject prior to enrollment into the study.

Phase 2: Baseline. The baseline phase aims to determine the stability and intra-subject variability of the pain sensations without treatment. These measure control for the daily variability in pain, assessment scoring variability, site to site variability and intra subject variability in the "before intervention" state. These variances will be used in the analysis to estimate baseline noise in each measure and measurement uncertainties against which statistical effect will be tested.

Phase 3: Entry. Entry assessments are to determine the entry assessment measures in the untreated case. They are divided into two protocols. All subjects will receive both assessment protocols. Protocol 1 includes the set of self-report measures of pain and sensation. Protocol 2 includes the application of cortical mapping methods using fMRI. The self-report measures of MAP (mapping of phantom pain perception and non-painful phantom sensation) and VAS (Visual Analogue Scale) are included to provide continuous longitudinal application of these instruments throughout the protocol.

Phase 4: Pre-therapy. This phase consists of one visit to set the stimulus ranges for the subject.

Phase 5: Therapy. Treatment will be provided on a daily basis for four (4) weeks. VAS and MAP are administered before and after the therapy to capture immediate transient effects of the therapy.

Phase 6: Outcome. This phase consists of the subjective and objective measures that define the end state of the subject immediately following the course of therapy. These outcomes will be tested against the Entry measures to determine the degree of the effect of the treatment on PLP and sensations. Outcome 1 (N or week 8) is carried out following the last therapy day and Outcome 2 is one week later.

Phase 7: Follow-up. Follow-up is assessed at weeks N+2, N+4 and N+8 (2, 4 and 8 weeks after last therapy day) in all cases. Most sensory feedback treatments have a carry over time course, where the effect carries on beyond the end of treatment. This phase assesses this time course. Subjects will be asked to complete the questionnaires or answer questions asked. Data will be collected through written questionnaires and verbal communication of sensations and pain either in person or over the telephone. ;

Related Conditions & MeSH terms

• Phantom Limb
• Phantom Limb Pain

• NCT number: NCT02519907
• Study type: Interventional
• Source: Indiana University
• Status: Active, not recruiting
• Phase: N/A
• Start date: September 2015
• Completion date: October 2019