Tan Timothy Shao Ern,  Teo Eu Leong Harvey James

Final Pr. ID: Poster #: EDU-062

Bone dysplasias comprise a group of congenital disorders characterized by anomalies in the development or texture of bone and cartilage, which can cause significant morbidity and mortality. Achondroplasia is the commonest bone dysplasia associated with rhizomelic dwarfism and is non-lethal. Other commonly encountered bone dysplasias include pseudoachondroplasia, hypochondroplasia, the mucopolysaccharidoses as well as disorders of disorganized bone development (i.e. diaphyseal aclasia, Trevor disease, enchondromatosis) and of abnormal bone density (i.e osteogenesis imperfecta, osteopetrosis, osteopoikilosis, osteopathia striata and melorheostosis).

The radiological diagnosis of bone dysplasias relies heavily on pattern recognition of established skeletal changes, which is often made on plain radiographs or skeletal survey. Whilst the radiographic features of bone dysplasias are generally well described in the axial and appendicular skeleton, its appearances in the lower limb, particularly of the foot and ankle, are usually less conspicuous compared to the rest of the skeleton. Moreover, the radiographic features may also overlap between dysplasia subtypes or mimic metabolic conditions. As such, accurate detection of these features can be challenging. Hence, knowledge and recognition of the radiographic features of bone dysplasias and its mimics presenting in the foot and ankle is crucial in aiding timely diagnosis, especially when interpreted together with other skeletal changes occurring elsewhere. Moreover, as bone dysplasias may be associated with other congenital disorders, radiologists play an essential role in directing further investigations for definitive diagnosis.

Thus, the purpose of this educational exhibit is to review and familiarize radiologists with the radiographic features and pattern recognition of commonly encountered bone dysplasias occurring in the paediatric foot and ankle, so as to guide appropriate management, aimed at preventing disabling deformities.The radiographic features of the above conditions presenting in the paediatric foot and ankle will be discussed and illustrated. Read More

Authors:  Tan Timothy Shao Ern , Teo Eu Leong Harvey James

Keywords:  Bone Dysplasia, Foot, Ankle

Handa Atsuhiko,  Nishimura Gen

Final Pr. ID: Poster #: EDU-058

A term “ciliopathy” represents a diverse group of genetic disorders caused by mutations in genes coding for components of the primary cilia. Primary cilia have a pivotal biological role in the cell surface of nearly every organ system of the body. "Skeletal ciliopathy" is a subset of ciliopathy mainly affecting the skeleton and shares common radiological findings such as short ribs, short limbs, and short digits with or without polydactyly. Pattern recognition approach is thus useful to diagnose skeletal ciliopathy. Skeletal ciliopathy includes (1) Jeune asphyxiating thoracic dysplasia, (2) Ellis-van Creveld syndrome (chondroectodermal dysplasia), (3) Sensenbrenner syndrome (cranioectodermal dysplasia), and (4) Short rib-polydactyly syndromes. Clinically, affected patients commonly present with thoracic hypoplasia with respiratory failure and disproportional stature with a normal trunk and short limbs most severe in the distal segments. Brachydactyly is conspicuous. Patients may have extra-skeletal anomalies such as retinopathy, cardiac anomalies, cerebellar malformations, and hepatorenal failures.
Radiological diagnosis of bone dysplasia might be regarded as something complex. We aim to highlight a pattern recognition approach to diagnose skeletal ciliopathies, one of the major bone dysplasias, by providing many cases. We will also review a general concept of "bone dysplasia family" which refers to a grouping of radiologically similar skeletal disorders into a “family.” This concept has been widely accepted now after we found that phenotypic similarities usually indicate the same/similar pathogenetic mechanisms, and it supports the use of a pattern recognition approach. Imaging diagnosis can guide genetic testing, interpretation, and possibly identify new genes or mutations. Read More

Authors:  Handa Atsuhiko , Nishimura Gen

Keywords:  Bone Dysplasia, Ciliopathy