title: Risk Factors for Reoperation in Patients Treated Surgically for Degenerative Spondylolisthesis: A Subanalysis of the 8-year Data From the SPORT Trial.
abstract: METHODS
  Retrospective analysis of prospective data from the degenerative spondylolisthesis (DS) arm of the Spine Patient Outcomes Research Trial.
  
  
  OBJECTIVE
  The aim of this study was to identify risk factors for reoperation in patients treated surgically for DS and compare outcomes between patients who underwent reoperation with nonreoperative patients.
  
  
  BACKGROUND
  Several studies have examined outcomes following surgery for DS, but few have identified risk factors for reoperation.
  
  
  METHODS
  Analysis included patients with neurogenic claudication (>12 weeks), clinical neurological signs, spinal stenosis, and DS on standing lateral x-rays. Univariate and multivariate analyses were used to investigate patient characteristics and risk factors. Treatment effects (TEs) were calculated and compared between study groups.
  
  
  RESULTS
  Of 406 patients, 72% underwent instrumented fusion, 21% noninstrumented fusion, and 7% decompression alone. At 8 years, the reoperation rate was 22%, of which 28% occurred within 1 year, 54% within 2 years, 70% within 4 years, and 86% within 6 years. The reasons for reoperation included recurrent stenosis or progressive spondylolisthesis (45%), complications such as hematoma, dehiscence, or infection (36%), or new condition (14%). Reoperative patients were younger (62.2 vs. 65.3, P = 0.008). Significant risk factors were use of antidepressants (P = 0.008, hazard ratio [HR] 2.08) or having no neurogenic claudication upon enrollment (P = 0.02, HR 1.82). Patients who were smokers, diabetics, obese, or on workman's compensation were not at greater risk for reoperation. At 8-year follow-up, scores for SF-36 bodily pain (BP), Oswestry Disability Index, American Academy of Orthopaedic Surgeons/Modems version (ODI), and stenosis frequency index were better in nonreoperative patients. TE favored nonreoperative patients for SF-36 BP, physical function, ODI, Stenosis Bothersomeness Index, and satisfaction with symptoms (P < 0.001).
  
  
  CONCLUSIONS
  The incidence of reoperation for patients with DS was 22% 8 years following surgery. Patients with a history of no neurogenic claudication and patients taking antidepressants were more likely to undergo reoperation. Outcome scores and TE were more favorable in nonreoperative patients.
  
  
  METHODS
  2.
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Gerling
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.|State University of New York, Downstate Medical Center, Brooklyn, NY.
authors.forename: Dante
authors.initials: D
authors.lastname: Leven
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Passias
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Virginie
authors.initials: V
authors.lastname: Lafage
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Kristina
authors.initials: K
authors.lastname: Bianco
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Lee
authors.affiliation: Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH.|The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, NH.
authors.forename: Tamara S
authors.initials: TS
authors.lastname: Morgan
authors.affiliation: Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH.|The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, NH.
authors.forename: Jon D
authors.initials: JD
authors.lastname: Lurie
authors.affiliation: Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH.|The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, NH.
authors.forename: Tor D
authors.initials: TD
authors.lastname: Tosteson
authors.affiliation: Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH.|The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, NH.
authors.forename: Wenyan
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, NH.|The Dartmouth Institute for Health Policy and Clinical Practice, Dartmouth College, Lebanon, NH.
authors.forename: Kevin F
authors.initials: KF
authors.lastname: Spratt
authors.affiliation: Rothman Institute of Thomas Jefferson University, Philadelpha, PA.
authors.forename: Kristen
authors.initials: K
authors.lastname: Radcliff
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, New York, NY.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Errico
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D001265:Athletic Injuries / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D001416:Back Pain / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D000078332:Data Analysis; D019299:Decompression, Surgical / Q000009:adverse effects / Q000639:trends; D005500:Follow-Up Studies; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D011446:Prospective Studies; D012086:Reoperation / Q000639:trends; D012189:Retrospective Studies; D012307:Risk Factors; D013130:Spinal Stenosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D013168:Spondylolisthesis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000601:surgery; D013177:Sports / Q000639:trends; D013997:Time Factors; D016896:Treatment Outcome