title: Autofusion in the immature spine treated with growing rods.
abstract: METHODS
  Retrospective case review of skeletally immature patients treated with growing rods. Patients received an average of 9.6 years follow-up care.
  
  
  OBJECTIVE
  (1) to identify the rate of autofusion in the growing spine with the use of growing rods; (2) to quantify how much correction can be attained with definitive instrumented fusion after long-term treatment with growing rods; and (3) to describe the extent of Smith-Petersen osteotomies required to gain correction of an autofused spine following growing rod treatment.
  
  
  BACKGROUND
  The safety and use of growing rods for curve correction and maintenance in the growing spine population has been established in published reports. While autofusion has been reported, the prevalence and sequelae are not known.
  
  
  METHODS
  Nine skeletally immature children with scoliosis were identified who had been treated using growing rods. A retrospective review of the medical records and radiographs was conducted and the following data collected: complications, pre- and postoperative Cobb angles at time of initial surgery (growing rod placement), pre- and postoperative Cobb angles at time of final surgery (growing rod removal and definitive fusion), total spine length as measured from T1-S1, % correction since initiation of treatment and at definitive fusion, total number of surgeries, and number of patients found to have autofusion at the time of device removal.
  
  
  RESULTS
  The rate of autofusion in children treated with growing rods was 89%. The average percent of the Cobb angle correction obtained at definitive fusion was 44%. On average, 7 osteotomies per patient were required at the time of definitive fusion due to autofusion.
  
  
  CONCLUSIONS
  Although growing rods have efficacy in the control of deformity within the growing spine, they also have adverse effects on the spine. Immature spines treated with a growing rod have high rates of unintended autofusion which can possibly lead to difficult and only moderate correction at the time of definitive fusion.
authors.affiliation: Shriners Hospital for Children-Philadelphia, Philadelphia, PA, USA. pcahill@shrinenet.org
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Cahill
authors.forename: Sean
authors.initials: S
authors.lastname: Marvil
authors.forename: Laury
authors.initials: L
authors.lastname: Cuddihy
authors.forename: Corey
authors.initials: C
authors.lastname: Schutt
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Idema
authors.forename: David H
authors.initials: DH
authors.lastname: Clements
authors.forename: M Darryl
authors.initials: MD
authors.lastname: Antonacci
authors.forename: Jahangir
authors.initials: J
authors.lastname: Asghar
authors.forename: Amer F
authors.initials: AF
authors.lastname: Samdani
authors.forename: Randal R
authors.initials: RR
authors.lastname: Betz
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D016268:Internal Fixators / Q000009:adverse effects / Q000592:standards; D008297:Male; D011183:Postoperative Complications / Q000209:etiology* / Q000473:pathology; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D011859:Radiography; D012189:Retrospective Studies; D012600:Scoliosis / Q000150:complications / Q000473:pathology / Q000601:surgery*; D013123:Spinal Fusion / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods*; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*