title: Association between compensation status and outcomes in spine surgery: a meta-analysis of 31 studies.
abstract: BACKGROUND
  Numerous studies have demonstrated poorer outcomes in patients with Workers' compensation (WC) when compared with those without WC following treatment of various of health conditions, including spine disorders. It is thus important to consider compensation status when assessing treatment outcomes in spine surgery. However, reported strengths of association have varied significantly (1.31-7.22).
  
  
  OBJECTIVE
  The objective of this study was to evaluate the association of unsatisfactory outcomes on compensation status in spine surgery patients.
  
  
  METHODS
  A meta-analysis was performed.
  
  
  METHODS
  Patient sample is not applicable in this study.
  
  
  METHODS
  Demographics, type of surgery, country, follow-up time, patient satisfaction, return to work and non-union events were the outcome measures.
  
  
  METHODS
  Both prospective and retrospective studies that compared outcomes between compensated and non-compensated patients in spine surgery were included. Two independent investigators extracted outcome data. The meta-analysis was performed using Revman software. Random effects model was used to calculate risk ratio (RR, 95% confidence interval [CI]) for dichotomous variables.
  
  
  RESULTS
  Thirty-one studies (13 prospective; 18 retrospective) with a total of 3,567 patients were included in the analysis. Follow-up time varied from 4 months to 10 years. Twelve studies involved only decompression; the rest were fusion. Overall RR of an unsatisfactory outcome was 2.12 [1.74, 2.58; p<.001] in patients with WC when compared with those without WC after surgery. The RR of an unsatisfactory outcome in patients with WC, compared with those without, was 2.09 [1.38, 3.17]; p<.01 among studies from Europe and Australia, and 2.14 [1.48, 2.60]; p<.01 among US studies. The RR of decompression-only procedures was 2.53 [1.85, 3.47]; p<.01,and 1.79 [1.45, 2.21]; p<.01 for fusion. Forty-three percent (209 of 491) of patients with WC did not return to work versus 17% (214 of 1250) of those without WC (RR 2.07 [1.43, 2.98]; p<.001). Twenty-five percent (74 of 292) and 13.5% (39 of 287) of patients had non-union in the compensated and non-compensated groups, respectively. This was not statistically significant (RR 1.33 [0.92, 1.91]; p=.07).
  
  
  CONCLUSIONS
  Workers' compensation patients have a two-fold increased risk of an unsatisfactory outcome compared with non-compensated patients after surgery. This association was consistent when studies were grouped by country or procedure. Compensation status must be considered in all surgical intervention studies.
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA. Electronic address: thomascheriyan@gmail.com.
authors.forename: Thomas
authors.initials: T
authors.lastname: Cheriyan
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: Bradley
authors.initials: B
authors.lastname: Harris
authors.affiliation: Department of Surgery, Marshfield Clinic, 1000 North Oak Avenue, Marshfield, WI 54449, USA.
authors.forename: Jerry
authors.initials: J
authors.lastname: Cheriyan
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: Virginie
authors.initials: V
authors.lastname: Lafage
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Spivak
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: John A
authors.initials: JA
authors.lastname: Bendo
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Errico
authors.affiliation: Division of Spine Surgery, Hospital for Joint Diseases, New York Langone Medical Center, New York, NY 10003, USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Goldstein
mesh_terms: D000328:Adult; D019299:Decompression, Surgical / Q000009:adverse effects / Q000191:economics*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D013131:Spine / Q000601:surgery*; D014942:Workers' Compensation
keywords: Meta-analysis; Outcome; Return to work; Spine; Unsatisfactory; Workers' compensation