The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine.

Paget's disease (PD) is a chronic metabolically active bone disease, characterized by a disturbance in bone modelling and remodelling due to an increase in osteoblastic and osteoclastic activity. The vertebra is the second most commonly affected site. This article reviews the various spinal pathomechanisms and osseous dynamics involved in producing the varied imaging appearances and their clinical relevance. Advanced imaging of osseous, articular and bone marrow manifestations of PD in all the vertebral components are presented. Pagetic changes often result in clinical symptoms including back pain, spinal stenosis and neural dysfunction. Various pathological complications due to PD involvement result in these clinical symptoms. Recognition of the imaging manifestations of spinal PD and the potential complications that cause the clinical symptoms enables accurate assessment of patients prior to appropriate management.

• Sonoelastography helps clarify ambiguous soft-tissue lesions identified using conventional ultrasound techniques. • Addition of this tool increases the diagnostic accuracy of ultrasound. • Sonoelastography provides both qualitative and quantitative analysis. • Sonoelastography may help clinicians improve patient care.

Spina bifida patients showed lower BMD, vitamin D, and electrolyte values than the healthy population; hence, they have an increase risk of developing pathological fractures. Vitamin D supplementation for a longer time period could reduce this risk.

Costello syndrome (CS) is a neurodevelopmental disorder with a distinctive musculoskeletal phenotype and reduced bone mineral density (BMD) caused by activating de novo mutations in the HRAS gene. Herein, we report the results of a prospective study evaluating the efficacy of a 4-year vitamin D supplementation on BMD and bone health. A cohort of 16 individuals ranging from pediatric to adult age with molecularly confirmed CS underwent dosages of bone metabolism biomarkers (serum/urine) and dual-energy X-ray absorptiometry (DXA) scans to assess bone and body composition parameters. Results were compared to age-matched control groups. At baseline evaluation, BMD was significantly reduced (p ≤ 0.05) compared to controls, as were the 25(OH)vitD levels. Following the 4-year time interval, despite vitamin D supplementation therapy at adequate dosages, no significant improvement in BMD was observed. The present data confirm that 25(OH)vitD and BMD parameters are reduced in CS, and vitamin D supplementation is not sufficient to restore proper BMD values. Based on this evidence, routine monitoring of bone homeostasis to prevent bone deterioration and possible fractures in adult patients with CS is highly recommended. K E Y W O R D S bone metabolism biomarkers, bone mineral density, Costello syndrome, patient-centered care, personalized medicine, RASopathies 1 | INTRODUCTION Costello syndrome (CS, OMIM #218040) is a rare multisystem disorder belonging to a family of syndromes affecting development and growth collectively known as the RASopathies. These rare diseases share the upregulation of the RAS/mitogen-activated protein kinase (MAPK) signaling pathway as a common pathogenetic mechanism (Aoki et al., 2016;Tartaglia & Gelb, 2010). This signaling cascade controls a wide array of cellular processes (e.g., proliferation, migration, Abbreviations: 25(OH)vitD, 25 hydroxy vitamin D; B-ALP, bone alkaline phosphatase; BMC, bone mineral content; BMD, bone mineral density; CFCS, cardio-facio-cutaneous syndrome; CS, Costello syndrome; DXA, dual-energy X-ray absorptiometry; F-BMD, femur bone mineral density; FFM, fat free mass; FM, fat mass; FN-BMD, femoral neck bone mineral density; L-BMD, lumbar bone mineral density; MAPK, mitogen-activated protein kinase; NF1, neurofibromatosis type 1; NS, Noonan syndrome; PTH, parathyroid hormone; S-BMC, subtotal bone mineral content; S-BMD, subtotal bone mineral density; WBLH, whole body less head.