Dynamic principles in craniofacial surgery. Expander elements in craniofacial surgery

Abstract: Lannelongue & Lane described strip removal of ossified skull sutures in craniosynostosis in the 1890s. More complex osteotomies with bone grafting were developed during the 1960s. Dynamic techniques, utilizing force to direct the growing brain for skull reshaping was introduced by Jane 1978 with the p-plasty for sagittal synostosis. The Dynamic Cranioplasty for Brachycephaly (DCB) 1996 was followed by spring assisted craniectomies in 1998.To assess the efficacy and safety and to better understand dynamic principles applied to craniosynostosis surgery the following studies were undertaken: A. Ten brachycephalic children were operated with the DCB at 6 months. Long term cephalometric results and general outcome was analyzed. B. Twenty-six children with sagittal synostosis operated with the p-plasty technique at 6 months underwent psychometric testing preoperatively and at 2 years of age. Cephalometry, peri- and postoperative clinical variables and parent questionnaires were used for follow up. C. Ten patients with sagittal synostosis were operated at 3 months with strip craniectomies and springs and prospectively followed clinically and with cephalometry and parent questionnaires. D. On 32 rabbits operated with strip craniectomies serial X-rays were taken to study the effect of 2 springs of different material and strength. Samples of bone formed in the osteotomy gaps were obtained for histology.Results: The DCB yields skull shape normalization with few complications. The p-plasty rendered skull shape close to normal with no psychometrically detectable adverse effect on mental development. Surgical complications were few and parental satisfaction high. Springs of different force were found to affect speed of skull reshaping while both promoted vertical skull growth.Conclusion: Dynamic principles in craniofacial surgery as studied were found to be safe and efficient. Springs in conjunction with dynamic skull reshaping hold considerable promise for future exploitation. The technique renders less trauma for the patient.