title: Etiologies of failed back surgery syndrome.
abstract: METHODS
  Retrospective chart review.
  
  
  OBJECTIVE
  To report the epidemiologic data of nonsurgical and surgical etiologies of failed back surgery syndrome (FBSS) from two outpatient spine practices.
  
  
  BACKGROUND
  FBSS has been offered as a diagnosis, but this is an imprecise term encompassing a heterogeneous group of disorders that have in common pain symptoms after lumbar surgery. The current literature primarily diagnoses for the various etiologies of FBSS from a surgical perspective. To our knowledge, there is no study that investigates the myriad of surgical and nonsurgical diagnoses from a nonsurgical perspective.
  
  
  METHODS
  Specific inclusion and exclusion criteria were developed for a list of 42 nonsurgical and surgical differential diagnoses of FBSS. The determination of which category, surgical or nonsurgical, each diagnosis was placed into depended upon the categorization of those diagnoses in previously published literature on FBSS. Each of the authors reviewed the definitions, and they came to a unanimous agreement on each diagnosis' inclusion and exclusion criteria. Data extraction was then carried out in each of the two involved institutions by using the key words discectomy, laminectomy, and fusion to identify all the patients who had any combination of low back, buttock, or lower extremity pain after lumbar discectomy surgery. These charts were then individually reviewed to extract epidemiologic data.
  
  
  RESULTS
  A total of 267 charts were reviewed. One hundred and ninety-seven (197) charts had a complete workup. Of these, 11 (5.6%) had an unknown etiology, and 186 had a known diagnosis. Twenty-three (23) various diagnoses were identified. There was approximately an equal distribution between the incidences of nonsurgical and surgical diagnoses; 44.4% had nonsurgical diagnoses and 55.6% had surgical diagnoses. The most common diagnoses identified were spinal stenosis, internal disc disruption syndrome, recurrent/retained disc, and neural fibrosis.
  
  
  CONCLUSIONS
  FBSS is a syndrome consisting of a myriad of surgical and nonsurgical etiologies. Approximately one half of FBSS patients have a surgical etiology. Approximately 95% of patients can be provided a specific diagnosis.
authors.affiliation: Penn Spine Center, University of Pennsylvania Health System, Philadelphia, Pennsylvania 19104, USA. slipman@mail.med.upenn.edu
authors.forename: Curtis W
authors.initials: CW
authors.lastname: Slipman
authors.forename: Carl H
authors.initials: CH
authors.lastname: Shin
authors.forename: Rajeev K
authors.initials: RK
authors.lastname: Patel
authors.forename: Zacharia
authors.initials: Z
authors.lastname: Isaac
authors.forename: Chris W
authors.initials: CW
authors.lastname: Huston
authors.forename: Jason S
authors.initials: JS
authors.lastname: Lipetz
authors.forename: David A
authors.initials: DA
authors.lastname: Lenrow
authors.forename: Debra L
authors.initials: DL
authors.lastname: Braverman
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Vresilovic