Infectious osteomyelitis

• the name would suggest an infection of both the bone as well as the bone marrow, but instead these are usually just bone problems with possible secondary involvement of the marrow

• hematogenous etiology is seen in…

  • children

  • debilitated and/or elderly (Gram-negative organisms)

  • elderly with diabetes

  • IVDA

• bone involvement

  • in children, most of the problem is concentrated in the lower femur, upper tibia, and, to some extent, the humerus

  • in the adult, most of the problem lies within the vertebral column and the feet

  • Batson’s plexus, the venous plexus that connects the pelvic cavity to the vertebral column, facilitates the spread of GU infections to the bone

• blood flow is slow in the metaphysis, and infection can localize here

• direct trauma to the bone can also lead to osteomyelitis

X-ray

• lytic lesion in lower vertebra

• in the vertebral column, we often try to distinguish between osteomyelitis and infiltrative tumor

• while a tumor usually respects the intervertebral disc, osteomyelitis doesn’t

direct inoculation osteomyelitis

• in hip, knee, joint replacements, dormant infections surface when the prostheses loosen

• therefore, in a sense, the cause is iatrogenic

radiograph

• bone scan shows a hot area

• this was an osteomyelitis secondary to knee replacement

Category: Pathology Notes