title: [Imaging study of paravertebral muscle degeneration in degenerative lumbar instability].
abstract: OBJECTIVE
  To compare the paravertebral muscle (such as multifidus, erector spinae, psoas muscle) changes between the patients with degenerative lumbar instability and normal person by MRI and to observe the degeneration of paravertebral muscles. To analyze the relationship between paravertebral muscle degeneration and lumbar curvature of degenerative lumbar instability.
  
  
  METHODS
  Sixty patients with degenerative lumbar instability were retrospectively enrolled from December 2011 to July 2013 as degeneration group, meanwhile 60 health persons with no degenerative lumbar instability were selected as control group. No significant differences were found in the gender, age and body mass index between the two groups. The cross-sectional area(CSA) and percentage of fat infiltration area (FIA) of the paravertebral muscles at the L4-S1 levels were measured using T2-weighted axial MRI and Image J soft ware. And the lumbar curvature(expressed as lumbar lordosis angle) of all the patients in lumbar X-ray were measured in the two groups. The measured data were analyzed with independent samples t-test.
  
  
  RESULTS
  The difference of multifidus cross-sectional area and the percentage of fat infiltration in the patients of degenerative lumbar instability at the L4-L5, L5-S1 level, compared with the control group, was statistically significant (t = 2.768, t = 6.216, P < 0.05). Between the two groups, the percentage of fatty infiltration in erector spinae showed significant differences (t = 5.862, P < 0.05). The cross-sectional area of erector spinae and the degeneration of the psoas muscle between the two groups was not statistically significant. The lumbar lordsis angle in the patients with degenerative lumbar instability was (43.9 ± 15.6)°, which was higher than the (39.3 ± 14.2)° in control group (t = 2.915, P < 0.05).
  
  
  CONCLUSIONS
  Compared with the control group, patients with degenerative lumbar instability exists erector spinae and multifidus muscle degeneration, and erector spinae is more obvious. The degeneration among psoas muscle, erector spinae and multifidus muscle are inconsistent, which may be related to the increasing of the lumbar lordosis angle in the patients with degenerative lumbar instability.
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Xuchao
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China. Email:dingwyster@gmail.com.
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Ding
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Dalong
authors.initials: D
authors.lastname: Yang
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Ma
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Dongxiao
authors.initials: D
authors.lastname: Xie
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Haiying
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Kuan
authors.initials: K
authors.lastname: Lu
authors.affiliation: Department of Spinal Surgery, the Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
authors.forename: Sidong
authors.initials: S
authors.lastname: Yang
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D008161:Lumbosacral Region / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009133:Muscular Atrophy / Q000150:complications / Q000175:diagnosis* / Q000473:pathology