title: Comparison of Sagittal Spinopelvic Alignment between Lumbar Degenerative Spondylolisthesis and Degenerative Spinal Stenosis.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the differences in sagittal spinopelvic alignment between lumbar degenerative spondylolisthesis (DSPL) and degenerative spinal stenosis (DSS).
  
  
  METHODS
  Seventy patients with DSPL and 72 patients with DSS who were treated with lumbar interbody fusion surgery were included in this study. The following spinopelvic parameters were measured on whole spine lateral radiographs in a standing position : pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis angle (LL), L4-S1 segmental lumbar angle (SLL), thoracic kyphosis (TK), and sagittal vertical axis from the C7 plumb line (SVA). Two groups were subdivided by SVA value, respectively. Normal SVA subgroup and positive SVA subgroup were divided as SVA value (<50 mm and ≥50 mm). Spinopelvic parameters/PI ratios were assessed and compared between the groups.
  
  
  RESULTS
  The PI of DSPL was significantly greater than that of DSS (p=0.000). The SVA of DSPL was significantly greater than that of DSS (p=0.001). In sub-group analysis between the positive (34.3%) and normal SVA (65.7%), there were significant differences in LL/PI and SLL/PI (p<0.05) in the DSPL group. In sub-group analysis between the positive (12.5%) and normal SVA (87.5%), there were significant differences in PT/PI, SS/PI, LL/PI and SLL/PI ratios (p<0.05) in the DSS group.
  
  
  CONCLUSIONS
  Patients with lumbar degenerative spondylolisthesis have the propensity for sagittal imbalance and higher pelvic incidence compared with those with degenerative spinal stenosis. Sagittal imbalance in patients with DSPL is significantly correlated with the loss of lumbar lordosis, especially loss of segmental lumbar lordosis.
authors.affiliation: Department of Neurosurgery, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Jae Kwan
authors.initials: JK
authors.lastname: Lim
authors.affiliation: Department of Neurosurgery, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, Korea.
authors.forename: Sung Min
authors.initials: SM
authors.lastname: Kim
keywords: Degenerative spinal stenosis; Degenerative spondylolisthesis; Lumbar lordosis; Pelvic incidence; SVA; Sagittal spinopelvic alignment