title: Analysis of Segmental Mobility Following a Novel Posterior Apical Short-Segment Correction for Adolescent Idiopathic Scoliosis.
abstract: METHODS
  A prospective, nonrandomized, multicenter study.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the amount of motion present at instrumented but unfused segments and at motion segments adjacent to the instrumentation following application of a new posterior apical short-segment correction technique for correcting adolescent idiopathic scoliosis (AIS).
  
  
  BACKGROUND
  High-density pedicle screw instrumentation and posterior arthrodesis of all instrumented levels is the most common surgical treatment for AIS stabilization. The consequence of long fusion is an abnormal load on adjacent levels with an increased risk of future adjacent segment degeneration.
  
  
  METHODS
  This new system applied translational and derotational forces over a short apical segment. The short apical region was prepared for fusion while maintaining motion of unfused vertebral segments. Radiographic data were collected pre-operatively, at surgery, and at 3, 6, and 12 months after surgery.
  
  
  RESULTS
  Twenty-one female patients, mean age of 14.2 years (10.6-16.9 years) with Lenke 1A/1B curves, were enrolled. The range of motion in the unfused instrumented segment was significantly higher than the apical fused segment (11 vs. 0.9, P < 0.001). The range of motion of unfused vertebral levels distal to the construct at one year did not differ significantly from their respective pre-op values. When the analysis was extended to understand the impact of lower instrumented vertebra (LIV) on motion of unfused segments distal to the construct, it appeared that (1) the change in motion from pre-op to 12 months post-op as a function of LIV is not statistically significant; and (2) The motion of the unfused distal vertebral segments at 12 months does not statistically increase with a lower LIV.
  
  
  CONCLUSIONS
  Through one year, this novel technique achieved and maintained similar AIS correction to current posterior fusion techniques while maintaining the mobility of unfused motion segments with less implant density.
  
  
  METHODS
  4.
authors.affiliation: San Diego Spine Foundation, San Diego, CA.
authors.forename: Pooria
authors.initials: P
authors.lastname: Hosseini
authors.affiliation: Nuffield Orthopaedic Centre, Oxford University Hospital, Oxford, UK.
authors.forename: Colin
authors.initials: C
authors.lastname: Nnadi
authors.affiliation: Comenius University & UHB, Bratislava, Slovakia.
authors.forename: Ľuboš
authors.initials: Ľ
authors.lastname: Rehák
authors.affiliation: University Hospital Brno, Orthopaedic Department Faculty, Brno, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Repko
authors.affiliation: Nottingham University Queens Medical Centre, Nottingham, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: Grevitt
authors.affiliation: Medicabil Hospital, Bursa, Turkey.
authors.forename: Ufuk
authors.initials: U
authors.lastname: Aydinli
authors.affiliation: Albany Medical Center, 47 New Scotland Ave, Albany, NY.
authors.forename: Allen
authors.initials: A
authors.lastname: Carl
authors.affiliation: San Diego Spine Foundation, San Diego, CA.
authors.forename: Jeff
authors.initials: J
authors.lastname: Pawelek
authors.affiliation: Sonoran Spine Center, Tempe, AZ.
authors.forename: Dennis
authors.initials: D
authors.lastname: Crandall
authors.affiliation: San Diego Spine Foundation, San Diego, CA.
authors.forename: Behrooz A
authors.initials: BA
authors.lastname: Akbarnia
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D006801:Humans; D065289:Pedicle Screws; D011446:Prospective Studies; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology*; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D016896:Treatment Outcome