Use of frozen cranial vault bone allografts in the repair of extensive cranial bone defects

Abstract

In cranioplasty complexity is proportional to the size of the detect, particularly if greater than 50 cm2. If the patient's own bone flap is not available, allogenic frozen bone graft can be used instead. Between June 1990 and June 1995 twenty cranioplasties with allogenic frozen bone grafts were performed. Age of patients ranged between 23 and 63 years (average 38.4 years). Male/female ratio was 2:1.7. Size of craniectomy ranged between 65 and 150 cm2 (average 83.3 cm2). Follow-up ranged between 10 and 58 months (average 41 months). Donors were tested to rule out transmissible diseases, infections, sepsis and/or cancer. Bone grafts were removed under aseptic conditions, microbiological cultures were taken, wrapped in a gauze soaked with Gentamicin sulphate and Bacitracin, sealed in three sterilised vinyl plastic bags, and stored in a deep freezer for a minimum of 30 days (range 36-93 days, average 67 days), at a temperature of -80 degrees C. Grafts were placed in the defect after a step was carved on its borders to facilitate the contact between host and graft. Vancomycin 1 g. IV/12 hours and Ceftriaxone 1 g. IV/12 hours were administered for five days. Grafts were covered by means of scalp flaps. Only one required a musculocutaneous free flap. None was exposed, extruded or had to be removed. Plain skull X-ray studies showed progressive remodelling of the grafts. Partial resorption was observed in two (2/20, 10%) and loss of thickness in another 3/20 (15%), but with no changes in the contour. Biopsies were taken in 3/20 (15%) cases at a second surgical procedure. Areas of osteoclastic resorptive activity mixed with others of osteoblastic bone apposition, showed replacement with new bone. We conclude that cranial vault frozen allografts are a good alternative to autologous bone when the latter is absent or not present in sufficient amount.

Extracorporeal irradiation of tumorous calvaria: a case series

“…Different options have been described, including artificial prostheses, autologous and allogeneic bone graft, and autoclaving the autologous bone graft. 5,8,23,[29][30][31] Numerous publications have confirmed that autologous bone grafting is considered the standard means of cranial reconstruction and is associated with lower complication rates and better outcomes. 4,9,12,13,18,22,27,28,34 The advantages of autologous grafting include the avoidance of foreign material implantation, which may lead to inflammatory response, donor graft rejection, and higher infection rates.…”

“…1,35 Furthermore, because the patient's own calvaria is used, it may lead to better structural and cosmetic outcome, reduced operative time, and lowered cost. 5,12,[29][30][31]33 Autologous bone grafting options include heterotopic autologous bone graft and sterilized autologous bone graft. Heterotopic autologous bone graft requires harvesting of local unaffected calvaria, which may lead to donor site morbidity and increased operative time.…”

“…Heterotopic autologous bone graft requires harvesting of local unaffected calvaria, which may lead to donor site morbidity and increased operative time. [29][30][31]33 The sterilized autologous bone graft technique destroys invaded tumorous cells and allows for reimplantation of the patient's calvaria flap. [29][30][31]33 Traditionally, this has been accomplished by autoclaving the tumorous calvarial flap and was first described by Naffziger in 1936.…”

“…[29][30][31]33 The sterilized autologous bone graft technique destroys invaded tumorous cells and allows for reimplantation of the patient's calvaria flap. [29][30][31]33 Traditionally, this has been accomplished by autoclaving the tumorous calvarial flap and was first described by Naffziger in 1936. 19 Subsequent follow-up studies of this technique indicated no recurrence of tumor in the treated calvaria, but partial resorption was observed radiologically in 19% of the cases.…”

Intraoperative Extracorporeal Irradiation for the Treatment of the Meningioma-Infiltrated Calvarium

“…11,14 However, donor site morbidity, increased surgical complexity, and graft site resorption render this option less desirable. 11,14,17 Calvarial allografts 18 and xenografts 14 eliminate the risk of donor site morbidity but offer suboptimal cosmesis and risk infection and immunologic reactivity that are unacceptable in light of the available alternatives. Demineralized bone matrix represents a newer option for custom in situ cranioplasty that offers the advantages of osteoconductivity and minimized infectious and immunologic reactivity risks.…”