SEDC needs to be differentiated from achondroplasia, hypothyroidism; and other dysplasias with universal platyspondyly in young children including metatropic dysplasia
, thanatophoric dysplasia, achondrogenesis and hypophosphatasia.
Metatropic dysplasia (metatropic-changing hypertrophic achondroplasia) was described in 1966 by Maroteaux et al.
Radiographic skeletal survey revealed characteristic vertebra plana (dense wafer thin), dumbbell shaped long bones, kyphosis, halberd shaped pelvis, squared calcaneus and coccygeal appendage consistent with the diagnosis of metatropic dysplasia.
(5) Recent research has pointed out that mutations in TRPV4, a calcium permeable ion channel produce a phenotypic spectrum of skeletal dysplasias from the mild autosomal-dominant brachyolmia to SMDK to autosomal dominant metatropic dysplasia, suggesting that these disorders should be grouped into a new bone dysplasia family.
Understanding the clinical spectrum of metatropic dysplasia, careful patient selection and appropriate intervention has great potential for functional improvement and hence, leading an independent social life for these challenging cases.
Heterogeneity of metatropic dysplasia. Eur J Pediatr 1983 Jun-Jul;140(3):231-237.
Revisiting metatropic dysplasia: presentation of a series of 19 novel patients and review of the literature.
Metatropic dysplasia: clinical and radiographic findings in 11 patients demonstrating long-term natural history.
Mutations in the gene encoding the calcium-permeable ion channel TRPV4 produce spondylometaphyseal dysplasia, Kozlowski type and metatropic dysplasia. Am J Hum Genet 2009 Mar;84(3):307-315.
Operative treatment of bilateral hip dislocations in a child with metatropic dysplasia. J Pediatr Orthop B 2007 Mar;16(2):94-97.