Le Fort III midfacial distraction using an internal distraction device for syndromic craniosynostosis: device selection, problems, indications, and a proposal for use of a parallel bar for device-setting.

Le Fort III midfacial distraction using internal and external devices is a well-accepted procedure for the midfacial retrusion of craniosynostosis syndrome patients. The authors described 20 consecutive series of Le Fort III midfacial distraction using internal distraction devices. Two types of devices were utilized. One type was a zygoma-skull device (the anterior part of the device is attached to the zygoma, and the posterior part is attached to the skull), which was used in six cases. The other was a zygoma-zygoma device (the anterior and posterior parts of the device are attached to the osteotomized zygoma, respectively), which was used in 14 cases. Subject ages ranged 3-32 years. A 14-20-mm distraction length was obtained by 1 mm/day. Satisfactory distraction of the midface was obtained in 17/20 cases. In 3/6 cases in which a zygoma-skull device was used, an unsatisfactory result was obtained. In these three cases, a fracture of the zygomatico-maxillary suture was encountered, resulting in the Le Fort III portion being left behind. In all 14 cases in which a zygoma-zygoma device was used, a satisfactory result was obtained. During the distraction period, the connection of the distraction device was dislodged, resulting in re-connection in three cases. Slight asymmetry was noticed in two cases without any need for management. In order to obtain parallel setting of the bilateral distraction devices, a newly developed parallel bar was used and demonstrated to be effective.