title: Change in classification grade by the SRS-Schwab Adult Spinal Deformity Classification predicts impact on health-related quality of life measures: prospective analysis of operative and nonoperative treatment.
abstract: METHODS
  Multicenter, prospective, consecutive series.
  
  
  OBJECTIVE
  To evaluate responsiveness of the Scoliosis Research Society (SRS)-Schwab adult spinal deformity (ASD) classification to changes in health-related quality of life (HRQOL) after treatment for ASD.
  
  
  BACKGROUND
  Ideally, a classification system should describe and be responsive to changes in a disease state. We hypothesized that the SRS-Schwab classification is responsive to changes in HRQOL measures after treatment for ASD.
  
  
  METHODS
  A multicenter, prospective, consecutive series from the International Spine Study Group.
  
  
  METHODS
  ASD, age more than 18, operative or nonoperative treatment, baseline and 1-year radiographs, and HRQOL measures (Oswestry Disability Index [ODI], SRS-22, Short Form [SF]-36). The SRS-Schwab classification includes a curve descriptor and 3 sagittal spinopelvic modifiers (sagittal vertical axis [SVA], pelvic tilt, pelvic incidence/lumbar lordosis [PI-LL] mismatch). Changes in modifiers at 1 year were assessed for impact on HRQOL from pretreatment values based on minimal clinically important differences.
  
  
  RESULTS
  Three hundred forty-one patients met criteria (mean age = 54; 85% females; 177 operative and 164 nonoperative). Change in pelvic tilt modifier at 1-year follow-up was associated with changes in ODI and SRS-22 (total and appearance scores) (P ≤ 0.034). Change in SVA modifier at 1 year was associated with changes in ODI, SF-36 physical component score, and SRS-22 (total, activity, and appearance scores) (P ≤ 0.037). Change in PI-LL modifier at 1 year was associated with changes in SF-36 physical component score and SRS-22 (total, activity, and appearance scores) (P ≤ 0.03). Patients with improvement of pelvic tilt, SVA, or PI-LL modifiers were significantly more likely to achieve minimal clinically important difference for ODI, SF-36 physical component score (SVA and PI-LL only), SRS activity, and SRS pain (PI-LL only).
  
  
  CONCLUSIONS
  The SRS-Schwab classification provides a validated system to evaluate ASD, and the classification components correlate with HRQOL measures. This study demonstrates that the classification modifiers are responsive to changes in disease state and reflect significant changes in patient-reported outcomes.
  
  
  METHODS
  3.
authors.affiliation: *Department of Neurosurgery, University of Virginia Medical Center, Charlottesville, VA †Department of Orthopedic Surgery, University of California Davis, Sacramento, CA ‡Department of Orthopedic Surgery, NYU Hospital for Joint Diseases, New York, NY §Department of Neurosurgery, University of California San Francisco, San Francisco, CA ¶Department of Orthopedic Surgery, Baylor Scoliosis Center, Plano, TX ‖Department of Neurosurgery, Weill Cornell Medical College, New York, NY **Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, KS ††Department of Orthopedic Surgery, San Diego Center for Spinal Disorders, La Jolla, CA ‡‡Department of Orthopedic Surgery, Oregon Health Sciences University, Portland, OR; and §§Department of Orthopedic Surgery, Rocky Mountain Hospital for Children, Denver, CO.
authors.forename: Justin S
authors.initials: JS
authors.lastname: Smith
authors.forename: Eric
authors.initials: E
authors.lastname: Klineberg
authors.forename: Frank
authors.initials: F
authors.lastname: Schwab
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Shaffrey
authors.forename: Bertrand
authors.initials: B
authors.lastname: Moal
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Ames
authors.forename: Richard
authors.initials: R
authors.lastname: Hostin
authors.forename: Kai-Ming G
authors.initials: KM
authors.lastname: Fu
authors.forename: Douglas
authors.initials: D
authors.lastname: Burton
authors.forename: Behrooz
authors.initials: B
authors.lastname: Akbarnia
authors.forename: Munish
authors.initials: M
authors.lastname: Gupta
authors.forename: Robert
authors.initials: R
authors.lastname: Hart
authors.forename: Shay
authors.initials: S
authors.lastname: Bess
authors.forename: Virginie
authors.initials: V
authors.lastname: Lafage
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011788:Quality of Life / Q000523:psychology; D015203:Reproducibility of Results; D012600:Scoliosis / Q000145:classification* / Q000175:diagnosis* / Q000523:psychology; D011795:Surveys and Questionnaires / Q000592:standards*; D016896:Treatment Outcome