title: Lowest instrumented vertebra selection for Lenke 5C scoliosis: a minimum 2-year radiographical follow-up.
abstract: METHODS
  A radiographical follow-up and analysis.
  
  
  OBJECTIVE
  To investigate the postoperative curve change in Lenke 5C scoliosis, and to discuss how to select lowest instrumented vertebra (LIV).
  
  
  BACKGROUND
  5C curves are relatively rare in adolescent idiopathic scoliosis, and few studies have focused on this type of adolescent idiopathic scoliosis. Such questions as "How does the curve change over time in the postoperative period?" "Is LIV selection correlated with final correction and balance?" and "How should we select LIV for Lenke 5C curves?" need to be answered.
  
  
  METHODS
  We reviewed all the adolescent idiopathic scoliosis cases surgically treated in an institution from 2002 through 2008. Inclusion criteria were as follows: (1) patients with Lenke 5C curves who were treated with selective lumbar fusion; (2) minimum 2-year radiographical follow-up.All image data were available and all measurements were performed in picture archiving and communication systems. Standing posteroanterior and lateral digital radiographs were reviewed at 4 junctures: preoperative, immediate postoperative, 3 months, and 2 years postoperatively.
  
  
  RESULTS
  Thirty patients met the inclusion criteria. The following results were observed: (1) From the perspectives of both Cobb angle and vertebral translation, significant correction was achieved; (2) The correction obtained by surgery was well retained in the postoperative period; (3) Although preoperative spinal imbalance was common in this group of patients, the majority eventually attained balance at 2 years; (4) LIV selection was significantly correlated with the 2-year correction and balance; (5) In the literature as well as in this study, the overall preoperative LIV-center sacral vertical line distance is 28 mm and the overall preoperative LIV tilt is 25°.
  
  
  CONCLUSIONS
  In Lenke 5C scoliosis, preoperative spinal imbalance is common, although the majority of patients attain balance at 2 years. Significant correction loss is not common in the postoperative period. LIV selection significantly correlates with 2-year correction and balance. A translation of 28 mm and a tilt of 25° may be used as a general criterion for selecting LIV.
  
  
  METHODS
  2.
authors.affiliation: Department of Orthopaedics E, Aarhus University Hospital, Aarhus, Denmark. yu.wang@ki.au.dk
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Cody Eric
authors.initials: CE
authors.lastname: Bünger
authors.forename: Yanqun
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chunsen
authors.initials: C
authors.lastname: Wu
authors.forename: Haisheng
authors.initials: H
authors.lastname: Li
authors.forename: Benny
authors.initials: B
authors.lastname: Dahl
authors.forename: Ebbe Stender
authors.initials: ES
authors.lastname: Hansen
mesh_terms: D000293:Adolescent; D000328:Adult; D005500:Follow-Up Studies; D006801:Humans; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D011184:Postoperative Period; D057234:Preoperative Period; D011859:Radiography / Q000379:methods; D012600:Scoliosis / Q000000981:diagnostic imaging / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods*; D013997:Time Factors; D055815:Young Adult