title: Sensory testing in patients with postthoracotomy pain syndrome: Part 1: mirror-image sensory dysfunction.
abstract: OBJECTIVE
  Mirror-image sensory dysfunction (MISD) has not been systematically characterized in persistent postoperative pain.
  
  
  METHODS
  The presence of MISD was evaluated with standardized stimuli, in preoperative patients scheduled for a thoracotomy (n = 14) and in patients with postthoracotomy pain syndrome [PTPS (n = 14)]. The primary outcome was investigation of the areas of sensory dysfunction, evaluated twice by dynamic sensory mapping with metal rollers and a brush.
  
  
  RESULTS
  In PTPS patients, sensory dysfunction was present on the surgical side, and in 12 of 14 patients MISD was demonstrated. The total areas of sensory dysfunction [median (interquartile range)] were: day 1, 500 (289 to 636) cm and 60 (0 to 379) cm on the surgical and nonsurgical side (P < 0.005), respectively; and day 2, 355 (266 to 697) cm and 81 (0 to 202) cm on the surgical and nonsurgical side (P < 0.0002), respectively. Magnitudes of areas on the surgical side, respective of the nonsurgical side, did not significantly differ between the 2 days of investigation (P > 0.5). The agreement between test-retest assessments was fair to excellent on the surgical side but poor on the nonsurgical side. None of the PTPS patients experienced mirror pain.
  
  
  CONCLUSIONS
  MISD is a common finding in PTPS patients and deserves further study involving mechanism and clinical implications.
authors: Multidisciplinary Pain Center, Neuroscience Center Rigshospitalet, Copenhagen, Denmark. mads.u.werner@gmail.com
authors: Mads U
authors: MU
authors: Werner
authors: Thomas K
authors: TK
authors: Ringsted
authors: Henrik
authors: H
authors: Kehlet
authors: Kim
authors: K
authors: Wildgaard
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000150:complications* / Q000209:etiology*; D011446:Prospective Studies; D012677:Sensation / Q000502:physiology*; D012678:Sensation Disorders / Q000175:diagnosis* / Q000209:etiology*; D013908:Thoracotomy / Q000009:adverse effects*; D013997:Time Factors