Summary

Fronto-metaphyseal dysplasia (FMD) is a rare craniotubular bone disorder characterized by a characteristic face (with prominent supraorbital ridges, hypertelorism, downslanted palpebral fissures, broad nasal bridge, and micrognathia with anomalies of teeth) and skeletal anomalies (fusion of carpal bones, increased density of long bone diaphyses, flared metaphyses and scoliosis). In addition, restricted joint mobility with contractures in the digits or hearing loss may sometimes be present. More rarely, respiratory problems (sub-glottic stenosis or recurrent infection) and urologic abnormalities are associated. About 30 cases of FMD have been reported. Fronto-metaphyseal dysplasia belongs to the phenotypic spectrum of fronto-oto-palato-digital osteodyplasia that encompasses Melnick-Needles syndrome, oto-palato-digital syndrome types 1 and 2, and FMD. These syndromes are X-linked disorders, with sometimes minimal expression in carrier females. and are all due to mutations in the FLNA gene, encoding the cytoskeletal protein filamin A. The pathophysiology of the disease remains unknown. Prognosis depends on the severity of the signs. Some patients have a mild mental delay. Cranioplastic surgery may be offered. Multidisciplinary management must be adapted to each patient (orthopedic, paediatric, ear nose and throat, genetic counselling, etc.).