Augmented Reality Helps Ease Phantom Pain In Amputees

When patients could visualize controlling their missing arms, pain decreased significantly

Dec 05, 2016 at 2:30 PM ET

Amputees suffering from phantom limb pain are finding alleviation of the chronic condition through augmented reality, according to newly-published results from a clinical trial conducted by researchers at the Chalmers University of Technology.

Phantom limb pain, an ailment described as painful sensations that feel as though they are coming from the missing limb, occurs in at least 42 percent of patients requiring amputation.

This augmented reality therapy was tested in a clinical trial of 14 arm amputees who have not had luck with current methods of pain management for an average of 10 years. These methods include medications like antidepressants, opioids, anticonvulsants, beta-blockers, and muscle relaxants in combination with treatments like acupuncture and mirror box therapy (a very low-tech version of the AR therapy in which patients can see the visual representation of a limb where it is no longer present and trick their brain into thinking they’re itching the spot that’s bothering them).

“We selected the most difficult cases from several clinics,” lead researcher Max Ortiz Catalan said in a press statement, adding that eight of the patients partaking in the trial were not currently receiving any form of treatment following years of failed attempts. The other four were constantly medicated.

The new “phantom motor execution method” uses electric signals in muscles that once controlled the now-missing arm through sensors placed on the patient. Artificial intelligence then enables the patient to view an onscreen augmented reality depiction of their body in which they have a virtual arm that they can control as if it were part of their body. The patients underwent 12 sessions of this kind of therapy over eight months, reactivating areas of their brain that had gone dark since their amputations.

At the end of the trial, patients reported significant improvements in their experience with phantom limb pain. The pain in itself had decreased by 51 percent on average, with daily living and sleep interruption also decreasing significantly. Two of the four patients were able to drastically reduce their pain medication.

Next, the researchers will perform an even larger clinical trial with leg amputees as well as arm amputees, testing if even more treatment sessions can help cure the pain in its entirety.

The importance of new therapeutic methods for treating phantom pain will only grow as the overall population of Americans who have experienced limb loss is expected to hit as many as 3.6 million by 2050, up from only 1.6 million in 2005.