title: Cutaneous sensory outcomes from three transhumeral targeted reinnervation cases.
abstract: BACKGROUND
  Although targeted muscle reinnervation has been shown to be effective in enhancing prosthetic control for upper limb amputees, restored hand sensations have been variable. An understanding of possible sensory feedback channels is crucial in working toward more effective closed-loop prosthetic control.
  
  
  OBJECTIVE
  To compare sensory outcomes of different targeted sensory reinnervation approaches.
  
  
  METHODS
  Case series, cross-sectional, and retrospective.
  
  
  METHODS
  Three transhumeral amputees that had undergone different sensory reinnervation approaches were recruited. Skin pressure sensitivity thresholds and anatomic sensory mapping were performed using Semmes-Weinstein monofilaments. The clinical charts of the subjects were reviewed to compare the sensory maps performed during the earlier post-reinnervation period.
  
  
  RESULTS
  While the first two subjects achieved return of hand sensations on the stump skin in early follow-up, the maps showed attenuation over time. The last subject developed discrete sensations of all digits in the recipient cutaneous nerve territories away from the reinnervated muscles.
  
  
  CONCLUSIONS
  These findings confirm that it is feasible to restore hand sensation after transhumeral targeted reinnervation, but there is a significant intersubject variability. The intrafascicular approach may be particularly effective in restoring digit sensation and deserves further exploration, as do factors affecting stability of the hand maps over time.
  
  
  CONCLUSIONS
  In addition to enabling intuitive motor control of myoelectric prosthesis, targeted reinnervation can also result in sensory restoration of the hand. Documentation of sensory mapping present after reinnervation may assist with exploring future techniques for sensory enhancement, with the goal of working toward closed-loop prosthetic control.
authors.affiliation: University of Alberta, Edmonton, AB, Canada Glenrose Rehabilitation Hospital, Edmonton, AB, Canada jhebert@ualberta.ca.
authors.forename: Jacqueline S
authors.initials: JS
authors.lastname: Hebert
authors.affiliation: University of Alberta, Edmonton, AB, Canada.
authors.forename: K Ming
authors.initials: KM
authors.lastname: Chan
authors.affiliation: Glenrose Rehabilitation Hospital, Edmonton, AB, Canada.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Dawson
mesh_terms: D000671:Amputation, Surgical / Q000379:methods*; D000672:Amputation Stumps / Q000294:innervation*; D001186:Artificial Limbs; D003430:Cross-Sectional Studies; D004576:Electromyography / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D006811:Humerus / Q000601:surgery; D008297:Male; D009416:Nerve Regeneration / Q000502:physiology*; D019635:Neurosurgical Procedures / Q000379:methods*; D011474:Prosthesis Design; D012189:Retrospective Studies; D012494:Sampling Studies; D012677:Sensation / Q000502:physiology; D012684:Sensory Thresholds; D016896:Treatment Outcome
keywords: Targeted reinnervation; sensory outcomes; transhumeral amputation; upper limb prostheses