Hajdu–Cheney syndrome and syringomyelia

first described in 1948 by Nicholas Hajdu and Ralph Kauntze under the designation “cranio-skeletal dysplasia.”11 The first familial case involved a mother and her four children who suffered from acroosteolysis.5 Most reported cases are sporadic forms of the disease, and one third are familial forms with probable autosomal-dominant transmission.2,5 The syndrome is characterized by facial dysmorphism (smooth and long philtrum, thin lips, depression of the tip of the nose, thick eyebrows and coarse hair, and ptosis); maxillofacial anomalies (microretrognathism, premature loss of teeth, alveolar resorption, and mandibular hypoplasia); joint laxity; significant osteopenia of the entire skeleton,3 with fractures occurring particularly at the level of the fifth metatarsus; short stature; and dysplasia of the spine and long bones.8,13,25,27 This syndrome may be associated with anomalies of the urinary system (polycystic kidney disease),9,30 cardiac malformations (persistence of the arterial channel and interventricular communication), and/or hearing loss (transmission deafness). The diagnosis can be confirmed on x-ray films, which show acroosteolysis of the distal phalanges and dysplasia of the skull (wormian bone, bathrocephaly, open sutures, widening of the sella turcica, prominent occipital ridge, and platybasia). Fifty-seven cases of Hajdu–Cheney syndrome have been reported in the literature; nine patients presented with neurological signs related to malformation of the craniovertebral junction (Table 1). Platybasia, which is not specific to this syndrome, but was found in 53% of patients,2 is responsible for basilar impression followed by ascending luxation of the odontoid process. Neurological complications can occur in childhood, generally after 10 years of age; hydrocephalus is the most common complication. Syringomyelia associated with this disease has only been reported three times in the literature (in one adult and two 10-year-old children). We report on a 7-year-old boy with a sporadic form of Hajdu–Cheney syndrome involving very early and rapidly developing syringomyelia, who has now been followed for 3 years. The therapeutic problems related to rapid deformation of a growing spine and the anatomical problems specific to this syndrome made surgical treatment quite hazardous.