A Virtual Reality System for Treatment of Phantom Limb Pain using Game Training and Tactile Feedback

Phantom Limb Pain (PLP) affects many amputees and many conventional treatment methods have been proven unreliable. This paper describes the implementation of a PLP treatment system for upper-limb amputees, using Virtual Reality (VR) to create an illusion that they regain and can control both hands again, which may suppress PLP. The system uses motion capture sensors to track the movement of the intact hand and arm, and mirrors the hand movement to the amputated side in the Virtual Environment (VE). Electrical stimulation was used to provide haptic feedback. The system consists of three games: (1) a bending game where the user has to grab, move, bend and release a 'nunchuck' to encourage hand rotations, (2) a frequency discrimination game, where the user has to distinguish between haptic frequencies, by pressing different buttons, and (3) a location discrimination game, where the user has to distinguish between stimulation locations. The system was tested on three amputees with PLP over the span of three weeks. For two participants, the games encouraged the use of both intact and amputated hand while playing. These two participants also felt an increased control of the amputated limb.