Phantom Limb Pain
Conditions
Brief summary
This international, multi-center, double-blind, randomized, controlled clinical trial aims to evaluate the efficacy of Phantom Motor Execution (PME) and Phantom Motor Imagery (PMI) as treatments of Phantom Limb Pain (PLP). In PME, myoelectric pattern recognition (MPR) is used to predict motor volition and then use the decoded movements to control virtual and augmented reality environments (VR/AR), along with serious gaming (SG). The same device and VR/AR environments are used in PMI with the difference that subjects will imagine rather than execute phantom movements. Electromyography is used to monitor for no muscular activity in PMI.
Detailed description
Sixty-six subjects with upper or lower limb amputations are planned to take part in this study. Subjects will be assigned randomly to PME and PMI treatments (2:1 proportion). After treatment completion (15 sessions of 2 hours each) and follow-up period of six months, patients that received PMI will be given the choice to receive PME. The design is double blinded as the patient will be informed that the treatment received, regardless of which, has been shown effective in previous studies. The person conducting the pain evaluations will be blinded to which treatment each patient receives, and will not take part on providing treatment (evaluator and therapist are different persons).
Interventions
Neuromotus - PME decodes motor volition applying machine learning to surface electromyography. Once the intention of movement is known, this is use to control serious games in virtual and augmented reality. A treatment session of MPE consists of: 1. Pain evaluation 2. Placement of the electrodes and fiducial marker 3. Practice of motor execution in Augmented Reality (AR) 4. Gaming using phantom movements 5. Practice of motor execution by matching random target postures of a virtual limb. Step 3 to 4 are repeated for different phantom joints, initially one at the time progressing to several joints simultaneously. A treatment session last 2 hours.
The only difference between PME and PMI is that in the former myoelectric signals are used to give the participants control over the virtual environments, whereas in PMI the presence of myoelectric activity is used as an alarm to remind the participant that it must imagine rather than execute the phantom movement. In PMI the virtual environments act autonomously to guide the participant in imagination of movement.
Sponsors
Study design
Masking description
Participants will be informed that both treatments have been shown effective in previous studies, and in the present study we are comparing their efficacy. The person conducting the pain evaluation (outcomes assessor) will not treat the participants and will be unaware of which treatment is given to each participant. The person treating the subject is different than the person evaluating. The principal and coordinating investigator will receive blinded data from all participating centers to analyze the clinical trial outcomes.
Intervention model description
International, multi-centre, double-blind, randomized, controlled clinical trial
Eligibility
Inclusion criteria
* Subject must be older than 18 years. * If the subjects are under pharmacological treatments, there must be no variations on the medicament dosages for at least one month (steady consumption). * The last session of previous treatments must be at least 3 months old. * Any pain reduction potentially attributed to previous phantom limb pain treatments must be at least 3 months old. * Subjects must have control over at least a portion of biceps and triceps muscles for upper limb amputations, and quadriceps and hamstrings for the lower limb amputations. * The subject has signed a written informed consent. * The subject must be in a stable prosthetic situation (i.e. satisfied with the fitting of the prosthesis) or being a non user. * At least six months should be passed since the amputation: acute phantom limb pain cases should not be included in the study. * The patient subject should not have a significant cognitive impairment that prevents the patient from following instructions. * Subjects with abundant soft tissue on their stump will not be automatically excluded, however, an evaluation in the system is required to analyze if sufficient electromyography signals can be recorded. * Subjects for whom skin contact or muscle contraction are painful (NRS \> 2) are not eligible for the study. * The subject should not have any condition associated with risk of poor protocol compliance. * The subject should not have any other condition or symptoms preventing the patient from entering the study, according to the investigator´s judgement.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pain Rating Index registered at the beginning (1st session) and at the end of the treatment (15th session). | 28-40 weeks, depending on the frequency of the sessions. | The Pain Rating Index (PRI) is calculated as the sum of 15 descriptors. At the end of each treatment session the descriptors are presented to the patient, who rates each of them with an intensity scale from 0 to 3. The PRI is therefore a number between 0 and 45: the higher the index the greater is the pain. The primary efficacy variable for this study is the change in PRI between the first and the last treatment session. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain Disability Index registered at the beginning (1st session) and the end of the treatment (15th session). | 28-40 weeks, depending on the frequency of the sessions. | The Pain Disability Index (PDI) measures the impact that pain has on the ability of a person to participate in essential life activities. The index is comprised between 0 and 70. The higher the index the greater the person's disability due to pain is. The secondary efficacy variable of this study is the change in PDI between the first and the last treatment session. |
Countries
Canada, Germany, Ireland, Netherlands, Slovenia, Sweden, United States