title: Impairments as measured by ISS do not greatly change between one and eight years after CRPS 1 diagnosis.
abstract: BACKGROUND
  Complex Regional Pain Syndrome type 1 (CRPS 1) is a potentially incapacitating complication in which pain seems to be the most disabling factor. We performed a late follow up study of a well-defined CRPS 1 population more than eight years after diagnosis. The relationships between early and late impairments were studied with a view to outcome prediction and to investigate possible differences in long-term impairments according to initial CRPS 1 subdiagnosis (i.e. "warm" or "cold", diagnosed according to skin temperature measured via infrared thermometer).
  
  
  METHODS
  We again measured patients using the Impairment Level SumScore (ISS) (T8). These data were compared with earlier ISS measurements at CRPS diagnosis (T0) and after one year's treatment (T1). Correlations were determined between these measures.
  
  
  RESULTS
  Forty-five patients participated in the present study. Total median ISS improved by 55% (statistically/clinically significant) after one year's treatment (T1), and worsened (non-significantly) by 14% from T1 to T8 - without differences according to original subdiagnosis. ISS correlations were stronger for T1 vs. T8 than for T0 vs. T1 or T0 vs. T8, being strongest for the ISS factors related to pain.
  
  
  CONCLUSIONS
  Considerable impairments, as measured by ISS, are still present over eight years after first CRPS 1 diagnosis. These do not greatly change between one and eight years post-diagnosis. ISS outcomes are similar for "cold" and "warm" CRPS 1 diagnostic subgroups. Component ISS scores associated with pain appear to possess greatest predictive power.
authors.affiliation: Pain Centre, Department of Anaesthesiology, Radboud University Medical Centre Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
authors.forename: Michiel
authors.initials: M
authors.lastname: Vaneker
authors.forename: Oliver H G
authors.initials: OH
authors.lastname: Wilder-Smith
authors.forename: Patrick
authors.initials: P
authors.lastname: Schrombges
authors.forename: H Margreet
authors.initials: HM
authors.lastname: Oerlemans
mesh_terms: D000328:Adult; D000368:Aged; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000379:methods; D011379:Prognosis; D012019:Reflex Sympathetic Dystrophy / Q000175:diagnosis* / Q000503:physiopathology*; D020886:Somatosensory Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D013995:Time; D013997:Time Factors; D016896:Treatment Outcome