To gain access to the brain for neurosurgical procedures, holes are often cut in the skull. These holes are created by making one or more bur holes in the cranial bone and then cutting the bone to connect the bur holes. The segment of the cranial bone removed in this fashion is referred to as a cranial flap. Once the surgical procedure is complete, however, the cranial flap must be repositioned in the cavity created by its removal. This is done by placing the cranial flap in its original position and fastening the flap to the surrounding cranial bone.
Currently a number of methods for cranial flap fixation exist. One such method utilizes clamping designs to close the cranial flap. Generally, these designs consist of two circular disks that are attached via a stem or connecting rod. The cranial flap is fixated by squeezing the flap, along with the surrounding cranial bone, between the two disks. However, many current clamping designs are limited in that they use ratcheting mechanisms which have a finite displacement and have the potential to apply excessive force to the cranial flap and surrounding cranial bone. Furthermore, most existing clamping designs do not address the need to return to the surgical site without undue effort. Instead, they require instruments to pry the top disks from the stem. In addition, many current clamping designs require instrumentation that requires additional maintenance, cleaning, and sterilization, adding to the time hospitals must dedicate to such devices.