title: Progressive restoration of spinal sagittal balance after surgical correction of lumbosacral spondylolisthesis before skeletal maturity.
abstract: OBJECTIVE
  Spinopelvic alignment is crucial in assessing an energy-efficient posture in both normal and disease states, such as high-displacement developmental spondylolisthesis (HDDS). The overall effect in patients with HDDS who have undergone local surgical correction of lumbosacral imbalance for the global correction of spinal balance remains unclear. This paper reports the progressive spontaneous improvement of global sagittal balance following surgical correction of lumbosacral imbalance in patients with HDDS.
  
  
  METHODS
  The records of 15 patients with HDDS who underwent surgery between 2005 and 2010 were reviewed. The treatment consisted of L4-sacrum reduction and fusion via a posterior approach, resulting in complete correction of lumbosacral kyphosis. Preoperative, 6-month postoperative, and final follow-up postoperative angular measurements were taken from full-spine lateral radiographs obtained with the patient in a standard standing position. Radiographic measurements included pelvic incidence, sacral slope, lumbar lordosis, and thoracic kyphosis. The degree of lumbosacral kyphosis was evaluated by the lumbosacral angle. Because of the small number of patients, nonparametric tests were considered for data analysis.
  
  
  RESULTS
  Preoperative lumbosacral kyphosis and L-5 anterior slip were corrected by instrumentation. Transient neurological complications were noted in 5 patients. Statistical analysis showed a significant increase of thoracic kyphosis on 6-month postoperative and final follow-up radiographs (p < 0.001). A statistically significant decrease of lumbar lordosis was noted between preoperative and 6-month control radiographs (p < 0.001) and between preoperative and final follow-up radiographs (p < 0.001).
  
  
  CONCLUSIONS
  Based on the authors' observations, this technique resulted in an effective reduction of L-5 anterior slip and significant reduction of lumbosacral kyphosis (from 69.8° to 105.13°). Due to complete reduction of lumbosacral kyphosis and anterior trunk displacement associated with L-5 anterior slipping, lumbar lordosis progressively decreased and thoracic kyphosis progressively increased postoperatively. Adjusting the sagittal trunk balance produced not only pelvic anteversion, but also reciprocal adjustment of lumbar lordosis and thoracic kyphosis, creating a satisfactory level of compensated global sagittal balance.
authors.affiliation: Université Pierre et Marie Curie-Paris and Department of Paediatric Orthopaedics, Armand Trousseau Hospital, Paris; and.
authors.forename: Diala
authors.initials: D
authors.lastname: Thomas
authors.forename: Manon
authors.initials: M
authors.lastname: Bachy
authors.forename: Aurélien
authors.initials: A
authors.lastname: Courvoisier
authors.forename: Arnaud
authors.initials: A
authors.lastname: Dubory
authors.forename: Houssam
authors.initials: H
authors.lastname: Bouloussa
authors.forename: Raphaël
authors.initials: R
authors.lastname: Vialle
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000601:surgery*; D008141:Lordosis / Q000601:surgery; D008159:Lumbar Vertebrae / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery*; D008297:Male; D011187:Posture / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods; D013168:Spondylolisthesis / Q000473:pathology / Q000601:surgery*
keywords: HDDS = high-displacement developmental spondylolisthesis; lumbar lordosis; lumbosacral kyphosis; lumbosacral spondylolisthesis; pelvic incidence; spinal sagittal balance; thoracic kyphosis