Object. Fixation of cranial bone flaps should be reliable, safe, rapid, esthetically acceptable, and inexpensive. It should require minimal foreign material, and ideally it should produce no artifacts on neuroimaging. The authors describe a new procedure that meets these criteria.
Methods. In this procedure, the cranial bone flap is affixed by tightly packing into the surrounding kerf the shims of bone that are harvested from the under edge of the free bone flap and then securing the flap with absorbable sutures. The result is a keystone arrangement that locks the flap into the craniotomy site.
Conclusions. The bone shim method for cranial bone fixation was used successfully in 386 of 387 consecutive craniotomies in adults. This procedure for cranial flap fixation is reliable, safe, and rapid, and it achieves solid structural stability with excellent esthetic results. No special tools are required, and, because no plates, screws, or wire are used, all problems associated with these materials are avoided, including the artifacts on postoperative neuroimaging. This method is conceptually simple and quite inexpensive.