Nager acrofacial dysostosis: a rare genetic disorder causing bilateral temperomandibular joint ankylosis in a 10-year-old girl.

To cite: Kumar MH, Kumar MS, Kumar VS, et al. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/ bcr-2015-212949 DESCRIPTION A 10-year-old girl presented to the oral medicine department, with restricted mouth opening since childhood. Her family history revealed that she was the third child born of a consanguineous marriage. She was born after an unremarkable pregnancy, with a birth weight of 2.3 kg. Physical examination revealed downslanting palpebral fissures, microretrognathia, malar hypoplasia, a sloping forehead, high nasal bridge with an upturned nasal tip and short philtrum (figure 1). She was also noted to have short forearms, proximal radioulnar synostosis (figure 2), hypoplastic thumbs and relatively short overlapping toes (figure 3A, B). Oral examination revealed extremely poor oral hygiene with a narrow V-shaped short palate; the mouth opening was 15 mm. Lateral cephalogram showed an underdeveloped mandible with an extreme posterior inclination of the mandibular base and also complete obliteration of the temperomandibular joint (TMJ) space (figure 4). Panoramic radiographic examination showed reduced vertical height of ramus, and multiple impacted teeth in the maxilla and mandible, with complete obliteration of right and left TMJ space (figure 5). Hearing assessment by brain stem-evoked response audiometry showed a bilateral profound hearing loss. In this case, genetic analysis was not perfomed due to financial constraint. From the girl’s overall clinical and radiographic features, she was diagnosed as having Nager acrofacial dysostosis. The patient’s mother gave full informed written consent to this report being published. Nager syndrome was first recognised by Nager and de Reynier in 1948. They used the term acrofacial dysostosis to describe their patient. The syndrome (preaxial acrofacial dysostosis) is due to aberrations in development of the first and second branchial arches and limb buds. Nager acrofacial dysostosis is characterised by a variety of craniofacial features including malar hypoplasia, cleft palate and micrognathia. The limb anomalies associated with Nager acrofacial dysostosis are a significant feature of this syndrome and help the clinician to differentiate this entity from other craniofacial syndromes. Patients with Nager syndrome often require several surgical procedures for correction of congenital anomalies, including cleft palate repair and mandibular lengthening with distraction osteogenesis or orthognathic surgery, among others, including bone grafts and ramus reconstruction. Clinical management in these cases mainly depends on a multidisciplinary approach focused on treatment of symptoms. Panoramic radiograph and lateral cephalogram obtained during the initial diagnostic procedure revealed bilateral TMJ ankylosis. The patient was referred to the oral and maxillofacial surgery department and was motivated for surgical treatment. Figure 1 Downslanting palpebral fissures with microretrognathia and malar hypoplasia.