Study to Assess the Efficacy of Direct Observation and Mental Visualization of Foot Movements to Treat Bilateral Lower Limb Phantom Limb Pain

Study to Assess the Efficacy of Direct Observation and Mental Visualization of Foot Movements to Treat Bilateral Lower Limb Phantom Limb Pain

Because bilateral lower extremity amputees do not have an intact limb for use with the mirror, we are now proposing to conduct a pilot trial of two treatments for phantom limb pain (PLP) - direct observation of another person's foot moving versus mental visualization. The trial will last for 4 months and during the first month data will be gathered daily on the number of episodes of phantom limb pain, the average length of episodes, and the average intensity of pain in each phantom leg. In addition, the rapidity of pain relief, the length of therapy needed to sustain long-lasting pain relief, and whether use of these two treatment methods during rehabilitation can provide sustained and/or permanent pain relief will be determined. This study will test the hypothesis that direct observation of a limb while performing phantom limb movements will reduce phantom limb pain more than mental visualization of the phantom limb alone in subjects who have sustained a traumatic bilateral lower limb amputation.

A total of forty-two (42) subjects with bilateral lower extremity amputations will be enrolled. Subjects will be randomized for assignment into two treatment conditions: twenty-one (21) subjects will use direct observation of another person's foot movements while twenty-one (21) will use mental visualization of foot movements (which will serve as the control group). Subjects in each group will be further be randomized for assignment into six treatment groups: direct observation or mental visualization of right lower extremity movements alone, direct observation or mental visualization of left lower extremity movements alone, or direct observation or mental visualization of simultaneous bilateral lower extremity movements. Subjects will use their assigned therapy for 20 minutes daily. The subjects for this study will be recruited from the Walter Reed Army Medical Center (WRAMC) Amputee clinic. Up to sixty (50) subjects will be recruited and screened according to the inclusion and exclusion criteria since we expect that some may not qualify or drop-out sooner than the scheduled 4-month completion time.

Inclusion Criteria:

• Male or female subjects, 18 to 70 years of age, active duty military, beneficiary, or retiree.
• Written informed consent and written authorization for use or release of health and research study information.
• Traumatic bilateral lower limb amputation.
• No prior history of vertebral disk disease/condition, sciatica or radiculopathy.
• Normal neurological examination.
• Minimum of 3 phantom limb pain episodes each week in one phantom leg.
• Degree of pain evaluated by VAS scoring a minimum of 3 cm at time of screening for entry into study.
• Ability to follow study instructions and likely to complete all required visits.

Exclusion Criteria:

• Age less than 18 or greater than 70.
• Unilateral upper or lower limb amputation.
• Severe traumatic brain injury (TBI) - permanent or temporary impairments of cognitive, physical, and psychosocial functions with an associated diminished or altered state of consciousness - as indicated by neuropsychological screening which is currently performed routinely on patients by the TBI program at WRAMC and noted in the patient's medical record. Subjects with diagnosis of mild TBI following TBI testing, but with a normal score (>42) on the Test of Memory Malingering (TOMM) (parts 1 or 2) can be included in the study.
• Known uncontrolled systemic disease- known cancer not in remission, known on-going infection, lupus, kidney disease requiring dialysis, any other systemic disease which might affect ability to participate in this study to its conclusion
• Concurrent participation in another investigational drug or device study for phantom limb pain or participation in the 30 days immediately prior to study enrollment.
• Any condition or situation that, in the investigator's opinion, may put the subject at significant risk, confound the study results, or interfere significantly with the subject's participation in the study.
• Significant Axis I or II diagnosis determined by a neurologist in the 6 months prior to entry into the study, defined as a condition requiring initiation of medications or hospitalization with continuing medical treatment for the condition.
• Subjects with lack of effort as determined by the neurologist. Subjects will be screened for effort using the TOMM first in order to exclude those with blatant exaggeration or malingering.