pathogenesis
Last reviewed 01/2018
In children, the infection usually begins in the metaphysis of a long bone, often the proximal end of the femur. The metaphyses are prone to infection because the blood is supplied by terminal branches of the nutrient arteries. The relative vascular stasis favours bacterial colonisation.
In infants there is free anastomosis between metaphyseal and epiphyseal arterioles and so infection occurs in both locations.
Acute osteomyelitis in the adult is more common in the vertebrae than the long bones.
It is thought that a small haematoma is seeded with bacteria.
The source for the bacteraemia may be:
- in the child:
- infected umbilical cord
- septic tooth
- a boil or abscess
- in the adult:
- tooth brushing
- urethral catheter
- an indwelling arterial line, etc.