Sensory feedback prosthesis reduces phantom limb pain: proof of a principle

Background: Constrained functionality and phantom limb pain (PLP) are major concerns for forearm amputees. Neuroscientific investigations of PLP suggest that behaviorally relevant stimulation of the stump can decrease PLP. Furthermore the prosthesis user could use feedback information of the prosthesis hand for optimizing prosthesis motor control when handling soft and fragile objects. Somatosensory feedback information from a prosthetic hand may therefore help to improve prosthesis functionality and reduce phantom limb pain.

Objectives: We wanted to find out whether a two weeks training on a hand prosthesis that provides somatosensory feedback may help to improve prosthesis functionality and reduce phantom limb pain.

Methods: Eight forearm amputees with phantom limb pain were trained for two weeks to use a hand prosthesis with somatosensory feedback on grip strength.

Results: The current study demonstrates a significant increase of functionality of the prosthesis in everyday tasks. Furthermore, the study shows that usage of a prosthesis that provides somatosensory feedback on the grip strength is effective to reduce phantom limb pain.

Conclusions: A prosthesis with a feedback function appears to be a promising therapeutic tool to reduce phantom limb pain and to increase functionality in everyday tasks. Future studies should further investigate the scope of application of that principle.