Nov. 21, 2007 -- Mirrors may help curb phantom limb pain, a new study shows.
The new study on phantom limb pain tests a technique called mirror therapy.
Eighteen patients took part, each of whom had phantom limb pain from an amputated foot. First, they rated their phantom limb pain. Then they were split into three groups.
Patients in one group were assigned to mirror therapy. They watched themselves in a mirror as they tried to move their phantom limb.
Of course, the patients couldn't move an amputated foot. The point was to see if their brain and nerves would dim phantom limb pain based on what they saw in the mirror.
Patients in another group performed the same exercise, but their mirror was covered by a sheet, so they couldn't see themselves.
The third group of patients didn't use a mirror at all. Instead, they tried mental visualization, imagining themselves moving their amputated limb.
Mirror Therapy for Phantom Limb Pain
The patients practiced their assigned technique for 15 minutes per day for four weeks, and then they rated their phantom limb pain again.
All of the patients in the mirror therapy group reported a drop in their phantom limb pain. Two of them also had brief bouts of grief as they watched themselves in the mirror.
In comparison, one patient in the covered mirror group and two in the visualization group reported a reduction in phantom limb pain.
Phantom limb pain scores worsened for three patients in the covered mirror group, four in the visualization group, and none in the mirror therapy group.
The mirror may have provided visual feedback that turned down the brain's pain pathways, suggest the researchers, who don't know exactly how that process works.
They included Brenda Chan of the Walter Reed Army Medical Center in Washington, D.C., and Jack Tsao, MD, DPhil, of the Uniformed Services University of the Health Sciences in Bethesda, Md.
Their report appears in tomorrow's edition of The New England Journal of Medicine.