Long bone metaphyseal cupping is most likely due to the local oligaemia from thrombosis in the terminal epiphyseal arteries to the epiphyseal plate, induced by prolonged regional immobilisation 7.
The differential diagnosis of long bone metaphyseal cupping includes:
Common
- normal variant
- renal osteodystrophy
- rickets
- sickle cell anaemia
Less common
- paediatric fracture
- prolonged immobilisation
- scurvy
- hypophosphatasia
- achondroplasia
- metaphyseal dysplasias
- poliomyelitis (prolonged immobilisation)
- hypervitaminosis A
- post infection
- radiation-induced