Crab like ribs

Spondylocostal dysostosis {Jarcho-Levine syndrome}. It comprises of multiple malformations of the vertebrae and ribs coupled with a characteristic clinical picture of short neck, scoliosis, short trunk and deformities of the rib cage. {1,2} In the autosomal dominant form, affected children are short but otherwise the disorder runs a benign course. In contrast the autosomal recessive form succumbs to pneumonia in infancy or early childhood. Despite the abnormalities of the spine, the integrity of the spinal cord is not altered and the neurological function remains normal. The main clinical features are plagiocephaly {3} facial asymmetry, a short rigid neck and scoliosis. Radiographically, hemi- and fused vertebrae give rise to a short trunk, in severe cases. The spinal defects can be associated with absent or fused ribs. Turnpenny et al. {4} reported the clinical, radiographic and molecular findings in 10 families with autosomal recessive SCD, abnormal vertebral segmentation and the notch signalling pathway. Abnormal segmentation throughout the entire spine has been described as a predominating and a sole pathology. In recent years, genetic mapping and candidate gene sequencing approaches have identified causative mutations in four genes, all components of the Notch signalling pathway. SCDO1 {OMIM 277300} represents the majority of cases, as the present one and in which the underlying genetic cause has been identified and is due to mutation of the DLL3 gene with 27 distinct causative mutations identified to date. The closest differential diagnoses include neural tube defects which need to be evaluated. Eventually the prognosis has been considered directly related to respiratory complications. {5} The treatment includes surgical correction of the deformities by a team approach and regular follow-ups.

E-published: December 2012 Vol 9 Issue 12 Art # 79

References :

Bonafe L, Giunta C, Gassner M, Steinmann B, SupertiFurga A. A cluster of autosomal recessive spondylocostaldysostosis caused by three newly identified DLL3 mutations segregating in a small village. Clin Genet. 2003; 63: 28–35 Gellis SS, Feingold M. Spondylothoracic dysplasia (costovertebral dysplasia, Jarcho-Levin syndrome) Am J Dis Child. 1976; 130: 513–514 Kreiborg S, Bjork A. Craniofacial asymmetry of a dry skull with plagiocephaly. Eur J Orthod. 1981; 3: 195–203 Turnpenny PD, Whittock N, Duncan J, Dunwoodie S, Kusumi K, Ellard S. Novel mutations in DLL3, a somitogenesis gene encoding a ligand for the Notch signalling pathway, cause a consistent pattern of abnormal vertebral segmentation in spondylocostaldysostosis. J Med Genet 2003; 40: 333–339. Ramírez N, Cornier AS, Campbell RM, Carlo S, Arroyo S, Romeu J. Natural history of thoracic insufficiency syndrome: a spondylothoracic dysplasia perspective. J Bone Joint Surg Am 2007; 89: 2663–2675