Osteomyelitis, osteonecrosis, osteoradionecrosis Flashcards
what is osteomyelitis?
Inflammation of bone, almost always secondary to infection
What are the ways in which you can get osteomyelitis? (3)
- Through the bloodstream
- Extension from an adjacent site (eg: big abscess that erodes in the jaw)
- Direct implantation
How do children tend to get osteomyelitis?
Through the bloodstream
How do adults tend to get osteomyelitis?
Fractures, surgical infections or diabetic foot
What bacterium is the common cause of osteomyelitis?
Staph Aureus
What is the clinical presentation of osteomyelitis?
Fever, localised bone pain, overlying tenderness
What are the risk factors for osteomyelitis?
Infection, peri-implantitis, infected cyst, infected tumour, surgical wound, fibrous dysplasia, osteoporosis, osteopetrosis, pagets disease, immuno-compromised pts (DB, HIV)
Why is the mandible more susceptible to osteomyelitis?
blood supply is less oxygenated AND dense overlying cortical bone prevents penetration of periosteal blood vessels
What is the tx for osteomyelitis?
Empirical antibiotics (penicillin) as broad spectrum
Surgery to remove sequestrum (allows better blood supply) + antibiotics
What appearance will chronic osteomyelitis give on an x-ray
moth eaten/sequestrum of bone
what is the difference between osteomyelitis and alveolar osteitis? (3)
osteomyelitis spreads through bone, AO is localised
osteomyelitis is NOT self-limiting, AO will get better is untreated
osteomyelitis is more chronic
After how long should a socket have healed?
8 weeks
What is osteoradionecrosis?
bone necrosis in previously irradiated tissue lasting for at least 6 months without any tendency to heal
What is endarteritis obliterans?
ends of the vessels are obliterated which reduces the blood supply - lack of oxygen to the area = death of cells and reduced blood supply so bone cant repair itself + trauma/infection = necrotic bone
what are the clinical features of osteoradionecrosis?
severe pain
non-healing exposed bone
which individuals might be taking bisphosphonates
pagets disease
osteopetrosis
osteoporosis
metastasizing solid cancers
multiple myeloma
What is MRONJ?
exposed bone which has persisted for more than 8 weeks in patients with a history of treatment on the above medication and where there has been NO history of radiation therapy
What are some examples of bisphosphonates?
Alendronic acid
Zolendronic acid
Risedronate sodium
What are examples of biologics?
Denosumab, sunitinib
Who is at increased risk of BRONJ?
immunosuppression (steroids/methotrexate)
immunocompromised (DM/HIV)
other med (chemotherapy/anti-angiogencs)
What is osteonecrosis?
infarction of the bone marrow
What is the likely cause of osteonecrosis?
alcohol, steroids, fractures BUT VASCULAR INSUFFICIENCY (damage to the blood vessels which leads to ischemia and necrosis of the bone)
Is osteonecrosis septic?
NO it is ASEPTIC (there is no infection)
what is the presentation of osteonecrosis?
joint pain
MRI will sho bone marrow oedema
what is the management of osteonecrosis?
surgical decompression, grafts, joint replacement