title: Resorption of Autogenous Bone Graft in Cranioplasty: Resorption and Reintegration Failure.
abstract: OBJECTIVE
  Re-implantation of autologous skull bone has been known to be difficult because of its propensity for resorption. Moreover, the structural characteristics of the area of the defect cannot tolerate physiologic loading, which is an important factor for graft healing. This paper describes our experiences and results with cranioplasty following decompressive craniectomy using autologous bone flaps.
  
  
  METHODS
  In an institutional review, the authors identified 18 patients (11 male and 7 female) in whom autologous cranioplasty was performed after decompressive craniectomy from January 2008 to December 2011. We examined the age, reasons for craniectomy, size of the skull defect, presence of bony resorption, and postoperative complications.
  
  
  RESULTS
  Postoperative bone resorption occurred in eight cases (44.4%). Among them, two experienced symptomatic breakdown of the autologous bone graft that required a second operation to reconstruct the skull contour using porous polyethylene implant (Medpor®). The incidence of bone resorption was more common in the pediatric group and in those with large cranial defects (>120 cm(2)). No significant correlation was found with sex, reasons for craniectomy, and cryopreservation period.
  
  
  CONCLUSIONS
  The use of autologous bone flap for reconstruction of a skull defect after decompressive craniectomy is a quick and cost-effective method. But, the resorption rate was greater in children and in patients with large skull defects. As a result, we suggest compressive force of the tightened scalp, young age, large skull defect, the gap between bone flap and bone edge and heat sterilization of autologous bone as risk factors for bone resorption.
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Si Hoon
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Chan Jong
authors.initials: CJ
authors.lastname: Yoo
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Uhn
authors.initials: U
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Cheol Wan
authors.initials: CW
authors.lastname: Park
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Sang Gu
authors.initials: SG
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Gil Medical Center, Gachon University, Incheon, Korea.
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Kim
keywords: Autologous transplant; Cranioplasty; Resorption