title: Low Pelvic Incidence Is Associated With Proximal Junctional Kyphosis in Patients Treated With Growing Rods.
abstract: METHODS
  Retrospective review of a prospectively collected pediatric orthopedic spine database.
  
  
  OBJECTIVE
  To investigate whether pelvic incidence (PI) changes during growing rod treatment and to report the effects of PI, if any, on complications during treatment.
  
  
  BACKGROUND
  Growing rods have been demonstrated to correct spinal deformity in early onset scoliosis while allowing for spinal growth. There has been little investigation into the potential effects, if any, of abnormal PI on complications, especially proximal junctional kyphosis (PJK).
  
  
  METHODS
  We retrospectively reviewed clinical and surgical data from our prospectively collected pediatric orthopedic spine database. Our final cohort of 48 patients had at least one lateral radiograph throughout the course of treatment containing the femoral heads and sacral endplate, and a minimum follow-up of 2 years. Defined failures were identified prospectively. Radiographs were measured for PI and development of PJK.
  
  
  RESULTS
  Mean age at initial treatment was 6.9 years (range 2.8-10.8 yr), with 35 females and 13 males. The mean length of follow-up was 8.1 years (range 2.0-22.1 yr). No statistical change in PI was observed throughout this study (P = 0.655). Development of any failure as well as total number of failures was associated with younger age at initial treatment (P < 0.0005 for both). Development of PJK was associated with younger age at initial treatment (P = 0.030), female sex (P = 0.002), and lower mean PI (P = 0.042).
  
  
  CONCLUSIONS
  PI remains constant throughout growth and the course of treatment with growing rods. Low PI was associated with increased PJK. When using growing rods in early onset scoliosis patients with decreased PI, increased attention should be paid to sagittal plane balance in an attempt to avoid PJK.
  
  
  METHODS
  4.
authors.affiliation: Division of Pediatric Orthopaedic Surgery, Case Western Reserve University, Rainbow Babies and Children's Hospital, Cleveland, OH.
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Carender
authors.forename: William Z
authors.initials: WZ
authors.lastname: Morris
authors.forename: Connie
authors.initials: C
authors.lastname: Poe-Kochert
authors.forename: George H
authors.initials: GH
authors.lastname: Thompson
authors.forename: Jochen P
authors.initials: JP
authors.lastname: Son-Hing
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D001863:Bone Screws / Q000009:adverse effects / Q000639:trends*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007738:Kyphosis / Q000000981:diagnostic imaging* / Q000453:epidemiology; D008297:Male; D010384:Pelvic Bones / Q000000981:diagnostic imaging*; D011183:Postoperative Complications / Q000000981:diagnostic imaging* / Q000453:epidemiology; D011446:Prospective Studies; D012189:Retrospective Studies; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult