title: Sagittal balance and spinopelvic parameters after lateral lumbar interbody fusion for degenerative scoliosis: a case-control study.
abstract: METHODS
  Retrospective matched-cohort analysis.
  
  
  OBJECTIVE
  To evaluate the change in radiographical parameters in patients undergoing interbody fusion and posterior instrumentation compared with posterior spine fusion (PSF) alone for degenerative scoliosis.
  
  
  BACKGROUND
  Little is known about the effect of lateral interbody fusion (LIF) on sagittal plane correction in the setting of degenerative scoliosis. We performed a retrospective study to investigate these changes compared with PSF.
  
  
  METHODS
  Between 1997 and 2011, 33 patients had LIF at 181 levels between T8 and L5 vertebrae for the treatment of degenerative scoliosis (mean; 5 ± 2 levels). Of those, 23 patients had additional anterior lumbar interbody fusion (ALIF) at 37 levels between L4 and S1 vertebrae (mean; 1.6 ± 0.5 levels). A 1:1 matched control of patients who underwent PSF was performed. Patients were matched by age, sex, and diagnosis. Clinical and radiographical data were collected and compared between the matched cohorts.
  
  
  RESULTS
  Lumbar lordosis (LL) was significantly restored in the LIF ± ALIF compared with PSF cohort (44° ± 14° vs. 36° ± 15°, P = 0.02). The segmental LL over the 102 LIF levels significantly improved from 12°± 10° to 21°± 13° postoperatively (P < 0.0001). However, the change over the 37 ALIF levels was not significant (from 30° ± 15° to 29° ± 9°, P = 0.8). Sagittal plane alignment was improved in the LIF ± ALIF compared with PSF cohort and trended toward but did not reach significance (3.8 ± 3.2 cm vs. 6.2 ± 5.7 cm, P = 0.09). Sacral slope was significantly higher in the LIF ± ALIF compared with PSF cohort (33° ± 11° vs. 28° ± 10°, P = 0.03). Pelvic tilt was lower in the LIF ± ALIF compared with PSF cohort and trended toward but did not reach significance (22° ± 10° vs. 26° ± 10°, P = 0.08).
  
  
  CONCLUSIONS
  LL and sacral slope had mildly but statistically improved in the interbody fusion cohort compared with PSF cohort. Sagittal alignment and pelvic tilt trended toward but did not reach statistical significance. Segmental LL was improved at LIF levels more than at ALIF levels.
  
  
  METHODS
  3.
authors.affiliation: *Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN †Center of Orthopedic Research and Education (CORE) Institute, Sun City West, AZ ‡Department of Orthopedic Surgery, Guang An Men Hospital, Beijing, China; and §Department of Orthopedic Surgery, University of Hawaii, Honolulu, Hawaii.
authors.forename: Yaser M K
authors.initials: YM
authors.lastname: Baghdadi
authors.forename: A Noelle
authors.initials: AN
authors.lastname: Larson
authors.forename: Mark B
authors.initials: MB
authors.lastname: Dekutoski
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Cui
authors.forename: Arjun S
authors.initials: AS
authors.lastname: Sebastian
authors.forename: Bryan M
authors.initials: BM
authors.lastname: Armitage
authors.forename: Ahmad
authors.initials: A
authors.lastname: Nassr
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000000981:diagnostic imaging / Q000601:surgery*; D004856:Postural Balance / Q000502:physiology; D011859:Radiography; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods / Q000639:trends*