title: [Measurement and comparison of postoperative anterior cord space between C2-7 and C3-7 laminoplasty on MRI].
abstract: OBJECTIVE
  To investigate the effect of C(2-7) laminoplasty on postoperative anterior cord space (ACS) compared with C(3-7) laminoplasty, and to provide evidence for reasonable enlargement of decompression range cephalad.
  
  
  METHODS
  Fifty-seven Patients underwent cervical laminoplasty from February 2008 to October 2011 were studied retrospectively, which were divided into two groups by decompression range: Group C(3-7) and Group C(2-7). The pre-and post operative JOA scores,VAS scores of neek and shoulder pain, and cervical alignment were compared in each group. The postoperative ACS at each level from C(2-3) to C(7)-T(1) measured on MRI were compared between the two groups.
  
  
  RESULTS
  The postoperative JOA scores increased significantly in both groups. VAS scores and cervical alignment showed no significant difference. ACS at C(2-3) and C(3-4) was 6.13 mm (95%CI: 5.71-6.55) and 6.60 mm (95%CI: 6.10-7.11) respectively in Group C(3-7), which increased 2.5 mm and 2.1 mm respectively in Group C2-7 at the same segment, there was significant difference (P < 0.01). However, there was no significant difference of ACS at C(4-5) and any other caudal levels between the two groups.
  
  
  CONCLUSIONS
  Compared with conventional C(3-7) laminoplasty, the extensive decompression cephalad to C(2) leads to larger ACS at C(2-3) and C(3-4). When the mid-sagittal diameter of anterior compression is more than 6.10 mm at C(3-4), C(3-7) laminoplasty may cause insufficient decompression, and enlargement of decompression range cephalad should be considered.
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Yinze
authors.initials: Y
authors.lastname: Diao
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China. Email: sunyuor@vip.sina.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Shaobo
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Fengshan
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Shengfa
authors.initials: S
authors.lastname: Pan
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China.
authors.forename: Zhongjun
authors.initials: Z
authors.lastname: Liu
mesh_terms: D002574:Cervical Vertebrae / Q000601:surgery*; D019299:Decompression, Surgical / Q000706:statistics & numerical data*; D006801:Humans; D065406:Laminoplasty; D008279:Magnetic Resonance Imaging; D011184:Postoperative Period; D012189:Retrospective Studies; D016896:Treatment Outcome