Cranium and Midface Distraction Osteogenesis: Current Practices, Controversies, and Future Applications

Background: The adaptation of distraction osteogenesis (DO) to the midface and cranium in the 1990s and the advancements that followed at the turn of the century resulted in a shift of paradigm in craniofacial surgery. Because skeletal advancement was not sudden anymore, but incremental, the monobloc advancement became safer to perform. Because bone was generated in the distraction gap, bone grafts were no longer needed, and younger patients could benefit from craniofacial advancement. Today, DO is the most powerful tool to simultaneously correct both exorbitism and the respiratory impairment of the faciocraniosynostosis, but practices vary greatly between teams. Methods: Current practices, controversies, and near-term future applications will be outlined and discussed. Results: Our current treatment strategy for faciocraniosynostosis is based on early intervention (<18 months of age) to prevent irreversible brain damage. In the first 6 months of life, infants with faciocraniosynostosis receive posterior vault decompression. We currently use posterior vault distraction, using 2 internal distractors. Around 18 months of age, a frontofacial monobloc advancement with DO is performed. It further decompresses the brain, improves respiratory function, and corrects exorbitism. Because we operate at such an early age, we favor internal over external distractors. In severe faciocraniosynostosis, when midface hypoplasia causes major exorbitism endangering the eye or causes respiratory distress requiring a tracheotomy, we do not hesitate to perform a frontofacial monobloc advancement with DO before the age of 18 months, reinforcing the frontozygomatic junction with a plate and placing a transzygomatic pin. The pin is then connected to a traction rope. We frequently use the external distractors, which allow precise control over the rotation of the maxilla and are well tolerated after 5 years of age. When midface hypoplasia is very severe, we combine external and internal distractors. Conclusions: The ongoing debate between proponents of internal versus external distractors or 1-stage versus 2-stage approach is based mostly on anecdotal data. Multicenter prospective studies are necessary to bring objective data to answer these questions.