Endocrine bone disease Flashcards
What is rickets?
It is the deficient mineralisation of the growth plate in the paediatric population.
Abnormalities in calcium-phosphate homoeostasis disrupt endochondral ossification at open physes.
Who gets rickets?
- premature infants (especially if on parenteral nutrition)
- unbalanced infant nutrition: protracted exclusive breastfeeding, non-vitamin D supplemented formula-fed infants, vegetarian diets
- maternal vitamin D deficiency
- lack of sun exposure
In severe cases, rickets becomes apparent in the second year of life.
Imaging features of rickets
Excess of non-mineralised osteoid resulting in growth plate widening and abnormal configuration of the metaphysis:
- fraying: indistinct margins of the metaphysis
- splaying: widening of metaphyseal ends
- cupping: concavity of metaphysis
- pseudofracture on the compression side of bone known as Looser’s zone.
It is not surprising that these features are most prominent at the bones where growth is greatest:
- knee: distal femur, proximal tibia
- wrist: especially the ulna
- anterior rib ends: rachitic rosary
What is scurvy/hypovitaminosis C?
It is caused by a dietary lack of vitamin C (ascorbic acid), and is characterised by an increased bleeding tendency and impaired collagen synthesis resulting in osteoporosis and impaired wound healing.
Who gets scurvy?
Scurvy in adults is rare. Young children and older persons are predisposed to scurvy due to their diet. It does not occur before six months of age because maternal stores are maintained until then. Males and females are equally affected. Patients at risk include elderly males, alcoholics, smokers and those with malabsorptive diseases.
Patients may present with lethargy and malaise, bone pain, bleeding diathesis (e.g. bleeding gums, petechiae), and impaired wound healing.
Imaging features of scurvy
Imaging features of scurvy
- generalised osteopenia
- cortical thinning: “pencil-point” cortex
- periosteal reaction due to subperiosteal haemorrhage
- scorbutic rosary: expansion of the costochondral junctions (similar to the rachitic rosary appearance as seen in rickets
- haemarthrosis
- pathological fractures
What is acromegaly?
