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Object: The object of this report is to present a conceptual and technical approach for expanding the cranial vault, by distraction osteogenesis, in patients with craniocephalic disproportion secondary to pancraniosynostosis and in patients with complex syndromic craniofaciosynostoses undergoing operations for aesthetic improvement., Methods: The clinical characteristics, techniques used, outcome and complications for all patients who underwent cranial vault expansions with distraction osteogenesis in Children's Hospital of Denver were reviewed., Results: Twenty-six cranial vault expansions were done in 24 patients. Nineteen patients presented with intracranial hypertension. Twelve of these had pancraniosynostosis and 8 had a syndromic diagnosis. Large segments of cranial bone were translated in a controlled manner for distances up to 30 mm. All but one of the patients with intracranial hypertension experienced complete resolution., Conclusions: Cranial vault expansion by distraction osteogenesis has the great advantage, as the name implies, of generating new and vascularized autologous bone of the correct shape and in correct locations. The technique, although not simple and not risk free, is much less technically complicated and places patients at lower risk for the most serious complications than does single-stage vault expansion. Less soft tissue dissection and less devascularization of bone are required and there are no postoperative dead spaces. Distraction osteogenesis facilitates far greater vault expansions than do single-stage procedures and can be accomplished in any desired direction.

Early examples of intentional human cranial deformation predate written history. Intentional cranial deformation as an extreme has seemingly not persisted into this century. However, mild forms of this manipulation are still practiced by various groups worldwide. Accidental cranial deformation or mild forms of intentional cranial deformation may be encountered by the clinician or anatomist. We review the literature regarding intentional manipulation of the human cranium.

The deformities of craniofacial bones in brachycephaly (n = 2) and plagiocephaly (n = 2) were compared using three-dimensional skull replicas. In brachycephaly the bilateral deformities of the cranial base were similar to the unilateral deformities on the affected side in plagiocephaly. Shortening of the anterior-middle cranial fossas and expansion of the middle cranial fossas suggest downward and anterior displacement of both temporomandibular (TM) joints resulting in the underdevelopment of the middle-inferior facial bones, though this is less conspicuous in brachycephaly for three reasons. The most important one is that the patients have an imposing facial morphology characterised by high, protruding facial bones, as found on the affected side in plagiocephaly. Secondly, the frontal bones are flattened and positioned posteriorly in the anteroposterior direction, which also helps to mask the underdevelopment of the middle-inferior facial bones. Finally, as bony deformities are symmetrical in brachycephaly, they are not as obvious as they would be if they were unilateral.

An operative series of 45 patients with anterior synostotic plagiocephaly is analyzed. In the cases of six children it was not possible to visualize synostosis of the cranial sutures on plain X-ray films or three-dimensional CT. Primary procedures were performed at an average age of 14 months with an average postoperative follow-up of 47.5 months. Children were operated on either with lateral canthal advancement (5 cases), unilateral orbital advancement with "tongue in groove" (12 cases), or bilateral orbital advancement (28 cases). Excellent results were obtained in 33/45 patients, while 8/45 children required secondary minor revisions. Of the three different surgical techniques, the results achieved by the bilateral approach were considered better than those attained with the unilateral techniques. Osteotomies of the nasal bones are recommended in the cases of older children with severe nasal deviation associated with dislocation of the nasoethmoidal complex.

Why do the craniofacial bones grow asymmetrically in patients with plagiocephaly (unilateral coronal synostosis)? We obtained three-dimensional skeletal replicas of two patients with the condition and analysed the deformities of the facial bones. From this analysis we deduced that the asymmetric deformation of the facial bones in these patients was caused by a combination of three rotations: rotation of the calvaria toward the affected side because of premature synostosis of the coronal and sphenofrontal sutures; rotation of the facial bones on the horizontal plane toward the unaffected side caused by anterior displacement of the TM (temporomandibular)-joint on the affected side; and downward rotation of the facial bones toward the unaffected side caused by inferior displacement of the TM-joint on the affected side.

The controversy over the reliability of ectocranial suture status (open vs. closed) as an age estimation stimulated the pursuit of Meindl and Lovejoy's suggestion (Meindl and Lovejoy [1985] Am. J. Phys. Anthropol. 68:57-66) for large scale analysis. The extent of the sagittal suture closure was assessed in 3,636 skulls from the Hamann-Todd and Terry collections. The debate over whether cranial suture ossification represents a pathologic or an age-predictable pathologic process also stimulated a comparison with age and two stress markers, hyperostosis frontalis interna and tuberculosis. Sagittal suture closure was found to be age-independent and sexually biased. The wide confidence intervals (for age) appear to preclude meaningful application of suture status for age determination. No correlation was found with the tested biological stressors.

The following hypothetical statements can be made. 1) Increased intra-uterine compression of the human cranium during the third trimester appears to produce sagittal synostosis by irreversibly altering the still immature sutural tissue that separates the parietal bones. 2) Intra-uterine compression does not cause facial sutures to fuse because they are physically shielded by the larger neurocranium and their ligaments are sufficiently mature to survive a chronic compressive force. 3) Postnatal compression of cranial and facial sutures normally does not result in bony fusion because their vascularized, differentiated, mature ligaments are capable of repair and regeneration.

A 7-year-old boy was referred to the children's hospital because of gross oedema and tiredness. Massive proteinuria was found and the condition was diagnosed as a childhood nephrotic syndrome. Concomitantly, pathologically low levels of serum alkaline phosphatase were recorded, and this, together with generalized osteoporosis and premature synostosis of cranial sutures, led to a second diagnosis: hypophosphatasia. The patient's family history further confirmed this condition of a heritable defect of metabolism. Dental inspection revealed very carious teeth with characteristically enlarged pulp chambers in molars. Histological examination of an extracted tooth revealed an unusually wide zone of predentine with some other dentinal irregularities. No cement layer was found. The skeletal age and exfoliation of primary teeth, however, were normal, unlike most reported cases of hypophosphatasia. The patient's renal disease was treated mainly with corticosteroids. There is no treatment for hypophosphatasia.

A rare case of cloverleaf skull is reported that was not diagnosed in utero. The case is more unusual because it was not associated with hydrocephalus and was associated with prune belly.