title: Delayed recovery in patients with whiplash-associated disorders.
abstract: BACKGROUND
  Prognosis of whiplash injury has been found to be related to a number of sociodemographic, treatment and clinical factors. In the current study, we attempt to identify several novel prognostic factors for delayed recovery in whiplash-associated disorders (WADs), using a validated and reliable measure of recovery.
  
  
  METHODS
  Retrospective review of a large database of a national network of physiotherapy and rehabilitation service providers in Canada yielded 5581 individuals injured in motor vehicle collisions. Cases were grouped into 3 cohorts based on time lapsed between injury date and initial presentation. Acute (n=3075), early chronic (n=958) and chronic (n=1548) patient cohorts were compared regarding treatment outcome and relative distribution of 29 prognostic factors. Outcome was defined by a minimally important clinical change (10%) on a previously validated disability questionnaire between initial and discharge rehabilitation visits.
  
  
  RESULTS
  Analysis demonstrated positive outcomes to be proportionally fewer in the chronic cohort (52.1%) relative to the early chronic (61.4%), which was in turn lower than the acute cohort (72.3%). Furthermore, individuals presenting with chronic pain were more likely to: (1) be female; (2) present with lower limb pain or nonorganic signs; (3) have returned to work; (4) have retained a lawyer; or (5) have undergone previous spinal surgery, and were less likely to: (1) present with neck or midback pain; (2) live in Ontario or Nova Scotia; or (3) have modified duties upon return to work. Acute, early chronic and chronic cohorts were also found to differ in the distribution of several other prognostic factors at initial clinical visit.
  
  
  CONCLUSIONS
  Recovery in whiplash-associated disorder appears to be multifactorial with both medical and non-injury related factors influencing outcome. Further characterisation of these factors may prove invaluable in guiding future clinical treatment and referral practices.
authors.affiliation: Department of Diagnostic Radiology, Kingston General Hospital, Queen's University, 76 Stuart St., Kingston, ON, K7L2V7 Canada.
authors.forename: John A
authors.initials: JA
authors.lastname: Dufton
authors.forename: Silvio G
authors.initials: SG
authors.lastname: Bruni
authors.forename: Jacek A
authors.initials: JA
authors.lastname: Kopec
authors.forename: J David
authors.initials: JD
authors.lastname: Cassidy
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Quon
mesh_terms: D000063:Accidents, Traffic / Q000331:legislation & jurisprudence / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D000368:Aged; D002170:Canada / Q000453:epidemiology; D059350:Chronic Pain / Q000191:economics / Q000209:etiology* / Q000503:physiopathology / Q000534:rehabilitation; D015331:Cohort Studies; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D019458:Insurance Coverage; D008297:Male; D008875:Middle Aged; D019547:Neck Pain / Q000191:economics / Q000209:etiology* / Q000503:physiopathology / Q000534:rehabilitation; D011379:Prognosis; D020127:Recovery of Function; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D013997:Time Factors; D014911:Whiplash Injuries / Q000150:complications* / Q000191:economics / Q000503:physiopathology / Q000534:rehabilitation; D055815:Young Adult