title: Tactile feedback for relief of deafferentation pain using virtual reality system: a pilot study.
abstract: Previous studies have tried to relieve deafferentation pain (DP) by using virtual reality rehabilitation systems. However, the effectiveness of multimodal sensory feedback was not validated. The objective of this study is to relieve DP by neurorehabilitation using a virtual reality system with multimodal sensory feedback and to validate the efficacy of tactile feedback on immediate pain reduction.
  
  
  
  We have developed a virtual reality rehabilitation system with multimodal sensory feedback and applied it to seven patients with DP caused by brachial plexus avulsion or arm amputation. The patients executed a reaching task using the virtual phantom limb manipulated by their real intact limb. The reaching task was conducted under two conditions: one with tactile feedback on the intact hand and one without. The pain intensity was evaluated through a questionnaire.
  
  
  
  We found that the task with the tactile feedback reduced DP more (41.8 ± 19.8 %) than the task without the tactile feedback (28.2 ± 29.5 %), which was supported by a Wilcoxon signed-rank test result (p < 0.05).
  
  
  
  Overall, our findings indicate that the tactile feedback improves the immediate pain intensity through rehabilitation using our virtual reality system.
authors.affiliation: The Department of Mechano-Informatics, Graduate School of Information Science and Technology, the University of Tokyo, Eng. Bldg.2, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656. sano@isi.imi.i.u-tokyo.ac.jp.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Sano
authors.affiliation: The Department of Mechano-Informatics, Graduate School of Information Science and Technology, the University of Tokyo, Eng. Bldg.2, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656.
authors.forename: Naoki
authors.initials: N
authors.lastname: Wake
authors.affiliation: The Department of Mechano-Informatics, Graduate School of Information Science and Technology, the University of Tokyo, Eng. Bldg.2, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656.
authors.forename: Akimichi
authors.initials: A
authors.lastname: Ichinose
authors.affiliation: The Neurorehabilitation Research Center, Kio University, 4-2-2 Umaminaka, Kouryou-cho, Kitakatsuragi-gun, Nara, Japan, 635-0832.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Osumi
authors.affiliation: The Anesthesiology and Pain Relief Center, the University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656.
authors.forename: Reishi
authors.initials: R
authors.lastname: Oya
authors.affiliation: The Anesthesiology and Pain Relief Center, the University of Tokyo Hospital, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Sumitani
authors.affiliation: The Research Center for Advanced Science and Technology, the University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, Japan, 153-8904.
authors.forename: Shin-Ichiro
authors.initials: S
authors.lastname: Kumagaya
authors.affiliation: The Department of Mechano-Informatics, Graduate School of Information Science and Technology, the University of Tokyo, Eng. Bldg.2, 7-3-1, Hongo, Bunkyo-ku, Tokyo, Japan, 113-8656.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kuniyoshi
mesh_terms: D000368:Aged; D000671:Amputation, Surgical; D001132:Arm; D020516:Brachial Plexus Neuropathies / Q000209:etiology / Q000534:rehabilitation; D056228:Feedback, Sensory; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology* / Q000534:rehabilitation; D059408:Pain Management / Q000379:methods*; D010775:Photic Stimulation; D010865:Pilot Projects; D014110:Touch; D016896:Treatment Outcome; D014584:User-Computer Interface
keywords: Arm amputation; Bilaterality; Brachial plexus avulsion; Deafferentation pain; Phantom limb; Tactile feedback; Virtual reality