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Reconstruction of Calvarial Defects

We subdivide the calvarium into three zones, each with its special reconstructive requirements. Based on our experience with calvarial defects in 13 patients, we favor use of autogenous material, especially in the face of previous infection or a scarred recipient bed. Alloplasts give excellent forehead contour but alloplastic reconstruction should be delayed for 1 year after injury. Vascularized bone grafts maintain contour well. They are best suited to large periorbital defects. At other locations we favor split calvarial free bone grafts. Occasionally, the defect may be so large as to warrant grafts from multiple donor sites. Use of vascularized muscle helps eradicate infection, provides a vascularized bed for free bone grafts, and fills dead space. The frontal sinus is managed either by cranialization (if the posterior wall is involved) or by mucosal stripping with obliteration of the nasofrontal duct. Additional technical considerations include rigid bone fixation, surgical exposure through a bicoronal incision, and meticulous handling of bone grafts.