title: Epidural lysis of adhesions for failed back surgery and spinal stenosis: factors associated with treatment outcome.
abstract: BACKGROUND
  Failed back surgery syndrome (FBSS) is a challenging problem. One treatment advocated to treat FBSS is epidural lysis of adhesions (LOA). The results of studies examining LOA for FBSS have been mixed, but are limited because no study has ever sought to identify factors associated with outcomes.
  
  
  METHODS
  We performed this multicenter, retrospective study in 115 patients who underwent LOA for FBSS (n = 104) or spinal stenosis (n = 11) between 2004 and 2007. Twenty-seven demographic, clinical, and procedural variables were extracted from medical records and correlated with the outcome, defined as ≥50% pain relief lasting ≥1 month. Univariable analysis was performed, followed by multivariable logistic regression.
  
  
  RESULTS
  Overall, 48.7% (95% confidence interval [CI], 39.3%-58.1%) of patients experienced a positive outcome. In univariable analysis, those who had a positive outcome were older (mean age 64.1 years; 95% CI, 59.7-68.6 vs 57.2; 95% CI, 53.0-61.4 years; P = 0.02), while higher baseline numerical rating scale pain scores were associated with a negative outcome (mean 6.7 years; 95% CI, 6.0-7.3 vs 7.5; 95% CI, 6.9-8.0; P = 0.07). Use of hyaluronidase did not correlate with outcomes in univariable analysis (odds ratio [OR], 1.2; 95% CI, 0.6-2.5; P = 0.65). In multivariable analysis, age ≥81 years (OR, 7.8; 95% CI, 1.4-53.7), baseline numerical rating scale score ≤9 (OR, 4.4; 95% CI, 1.4-16.3, P = 0.02), and patients on or seeking disability or worker's compensation (OR, 4.4; 95% CI, 1.1-19.5, P = 0.04) were significantly more likely to experience a positive outcome.
  
  
  CONCLUSIONS
  Considering our modest success rate, selecting patients for epidural LOA based on demographic and clinical factors may help better select treatment candidates. Procedural factors such as the use of hyaluronidase that increase risks and costs did not improve outcomes, so further research is needed before these become standard practice.
authors.affiliation: From the *Department of Anesthesiology and Critical Care Medicine, Johns Hopkins School of Medicine; †Department of Physical Medicine & Rehabilitation, Johns Hopkins School of Medicine; ‡Department of Anesthesia & Operative Services, Womack Army Medical Center, Fort Bragg, North Carolina; §Department of Neurology, Johns Hopkins School of Medicine; ‖Johns Hopkins School of Medicine; ¶Departments of Anesthesiology and Critical Care Medicine & Physical Medicine and Rehabilitation; at Uniformed Services University of the Health Sciences.
authors.forename: Eugene
authors.initials: E
authors.lastname: Hsu
authors.forename: Levan
authors.initials: L
authors.lastname: Atanelov
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Plunkett
authors.forename: Nu
authors.initials: N
authors.lastname: Chai
authors.forename: Yian
authors.initials: Y
authors.lastname: Chen
authors.forename: Steven P
authors.initials: SP
authors.lastname: Cohen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004824:Epidural Space / Q000473:pathology / Q000601:surgery*; D055111:Failed Back Surgery Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013130:Spinal Stenosis / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery*; D000267:Tissue Adhesions / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery; D017211:Treatment Failure; D016896:Treatment Outcome