[Cleidocranial dysplasia: a case report]

A 3-month-old female infant who presented with patent sagittal suture and loss of weight is described. Physical examination revealed a large sagittal and metopic suture showing delayed closure, a high-arched palate, saddle nose, hypertelorism and nonpalpable edges of the bilateral clavicles. The clavicles also showed undue mobility. Radiological investigations of the cranial skeletal abnormalities revealed enlargement of the sagittal and metopic sutures, and the anterior and posterior fontanelles. A chest radiograph showed a small, bell-shaped thoracic rib cage with partial aplasia of both clavicles. On the basis of the clinical findings, cleidocranial dysplasia was diagnosed. Cleidocranial dysplasia is an uncommon generalized skeletal disorder which, as its name implies, shows striking involvement of the cranial vault and clavicles. The clinical features reflect a generalized defect of both membranous and endochondral bone formation. It is characterized by delayed ossification of the skull, aplastic or hypoplastic clavicles, delayed deciduous dentition, and hereditary characteristics. The amount of calvarial growth is generally small, and the shape remains nearly unaltered. In all cases, calvarial bone thickness increases with age, but in the midline, the fontanelle area, which is shown to be defective at the first examination, remains open in all cases. The midfrontal area is poorly developed and exhibits a groove in many patients. It is inherited as an autosomal dominant trait, with wide variability of expression but a high degree of penetrance. Cytogenetic abnormalities involving chromosome 6p21 have been reported with a cleidocranial dysplasia phenotype. Although psychosocial disorders associated with the abnormal facial and body features may occur, patients have a good overall prognosis and life expectancy. Skull deformity, and delayed closure of the fontanelles and cranial sutures are the most important problems for neurosurgeons. The postero-lateral fontanelle closes before adulthood, whereas the opening in the midfrontal sutural area may persist. Many children with cleidocranial dysplasia whom we have encountered have persisting fontanelles and patent sutures, but this does not seem to predispose them to an abnormal calvarial growth pattern, at least in the age groups investigated. Congenital midface retrusion in the presence of relative or absolute mandibular prognathism is also a major deformity. Care is supportive, including attention to neurosurgical, orthopedic, pediatric and dental problems.