Small Animal Ortho: Neoplasia Flashcards
What is the most common bone tumor that comprises 75% of bone tumores?
Osteosarcoma
What are the primary locations for osteosarcome?
distal radius to proximal humerus
tibia to femoral location in equal proportions
What are the 3 things to remember while taking a biopsy of potential bone neoplasia?
make skin incision small so it can be easily excised
chose the center of the lesion based on radiographs
and take 2-3 biopsy cores from the center of the lesion
What is the median survival time for osteosarcoma?
3-4 months with amputation alone
same survival time if no treatment
dogs <5 year had worse prognosis
What are the criteria that osteosarcoma must meet in order to have a limb sparing treatment be considered?
tumor grossly confined to limb
<50% of bone affected by tumor
no metastasis
distal radius or ulna best
BW & urine WNL
What prognosis does a vascularized bone graft have compared to amputation?
They have the same prognosis
3-4 month survival time
dogs <5 years have worse prognosis
How is a vascularized bone graft done in a nut shell?
Take new bone graft first
remove all articular cartilage for arthrodesis
keep as much vasculature intact as possible
What are the expectations of a vascularized bone graft?
periosteal new bone in 2 weeks
bridging callus in 4 weeks
graft united to proximal radius & radial carpal bone @ 8 weeks
graft hypertrophy by 3 weeks
What are the most common bacteria associated with chronic osteomyelitis?
Staphylococcus pseudintermedius
Staphylococcus aureus
What three parts of sequestra must be removed to heal properly?
Sequestrum
involcrum
cloaca
What is a sequestrum?
fragments of necrotic bone
What is a involcrum?
goo pocket around necrotic bone
What is a cloaca?
draining tract
How do you diagnose osteomyelitis?
Radiographs
Culture and sensitivity
What is the surgical management of osteomyelitis?
Removal of surgical implants
culture & sensitivity
debridement
long term antibiotics for 6-8 weeks
