Controlled Study of Farabloc for Chronic Phantom Limb Pain Among Veteran Amputees

Phantom limb pain (PLP)is a painful sensation perceived in the missing limb after amputation and may be triggered by episodes of stump pain. A growing body of literature indicates that 50-80% of amputees may have PLP. Farabloc cloth is a noninvasive, alternative therapy developed by Farabloc Development Corporation for use by amputees with PLP. The Farabloc Corporation will be donating them to the VA Long Beach for use in this study without charge. Farabloc is a non-toxic and non-invasive treatment with promising preliminary pilot data. Metallic fibers consisting mainly of iron (85.3%) and nickel (10.0%) are woven into a nylon fabric that can be custom made into socks, gloves, limb covers, etc. Farabloc can be laminated into the socket and in the design of the prosthetic without weakening or adding significant weight to it. The exact mechanism of action is unknown for Farabloc, however, it is theorized that the fabric shields high frequency electromagnetic fields that may cause cellular damage and subsequent pain.

Subjects over 18 will be recruited from the VA Long Beach Prosthetic Clinic. Eligible subjects who are interested to participate, will be scheduled for a screening visit. Written informed consent will be obtained before enrollment. Enrolled subjects will be randomly assigned to either the Farabloc or sham Farabloc group. Assignment is double-blind to study participants, prosthetist, Farabloc Corporation and the research assistant throughout the study. Only the project coordinator and PI will know the random assignment.

Farabloc intervention will consist of wearing prosthetics laminated with Farabloc surrounding the liner or, if not wearing prosthetics, subject will wear Farabloc sock or glove over shrinker. Sham intervention will consist of wearing prosthetics laminated with sham fabric surrounding the liner or, if not wearing prosthetics, subject will wear sock or glove made of sham fabric over shrinker. All subjects will receive at least two socks.

Data for PLP pain levels and health-related quality of life will be collected during baseline, 6-week, 12-week and 1-month post treatment follow-up. Research staff will administer these surveys and collect data in person. The amount of health care utilization will be measured 12-week prior ot enrollment and 12-week follow-up. Monitoring adherence to protocol by phone call will be made during the treatment at 3-week and 9-week followup.

Study participants will receive a total of $50 for their participation in this study ($20 for baseline and $10 for each of the three follow-up visits). At the end of the study, participants can choose to keep the active or sham Farabloc. If the true Farabloc turns out to be an effective treatment for phantom limb pain, subjects assigned to the sham Farabloc intervention will b offered the option to be treated with true Farabloc free of charge aftr conclusion of the study.

Inclusion criteria

• Upper or lower extremity amputees with healed stumps
• Experience episodes or intermittent PLP
• At least 3 episodes of PLP during the previous 6 weeks
• Have not used Farabloc within the last 6 months

Exclusion criteria

• Pregnant women are excluded from the study
• Stump complications (e.g., cellulites and stump pain caused by new bone spur within the past 12 months
• Previous use of Farabloc within 6 months