title: [Correlation between pelvic indices, pelvic spatial orientation and lumbar vertebrate instability].
abstract: OBJECTIVE
  To explore the correlation between the stability of lumbar vertebrate and pelvic indices of pelvic incidence (PI), lumber lordosis (LL), pelvic tilt (PT) and sacrum slope (SS).
  
  
  METHODS
  The preoperative imaging data were analyzed retrospectively for 78 patients with lumbar disc protrusion. The values of PI, PT, SS and LL were measured and compared between lumbar vertebrate stability and lumbar vertebrate instability groups.
  
  
  RESULTS
  No inter-group statistical difference existed in PI, LL, PT or SS. The average PI of lumbar vertebrate instability group was higher than that of lumbar vertebrate stability group.In patients with L4/5 segmental lesion, SS of lumbar vertebrate instability group was higher than that of lumbar vertebrate stability group (38.7 ± 4.7)° vs (34.0 ± 6.6)°, P = 0.023. And PT in patients with L5/S1 segmental lesion was higher than those with L4/5 segmental lesion (17.5 ± 7.0 vs 14.9 ± 5.3, P = 0.027).
  
  
  CONCLUSIONS
  No statistical inter-group difference exists in PI. However, higher SS and PT may be risk indicators of instability for L4/5 and L5/S1 segments respectively.
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Siyi
authors.initials: S
authors.lastname: Cai
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Surong
authors.initials: S
authors.lastname: Hua
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Jianxiong
authors.initials: J
authors.lastname: Shen
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. Email: lishugang@medmail.com.cn.
authors.forename: Shugang
authors.initials: S
authors.lastname: Li
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000473:pathology*; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000473:pathology*; D012189:Retrospective Studies