Flashcards in Osteomyelitis and Ostosarcoama (Pead) Deck (20):
What type of iseae is osteomyelitis?
Which types of diseae are common in bone and joints?
> Infectious (myelitis)
> Neoplastic (Osteosarc)
> Trauma (fx)
- vascular (rare)
- autoimmune (rare)
- degenerative (more joints)
- inflammatory (more joints)
Strict defintition of osteomyelitis? Used for?
> infection of corticol bone and medullary cavity
- used for any infection of bone
What i osteitis?
- term used by pahologists
- describes infection of cortex without involveent of red or yellow BM
What forms of osteomyelitis?
- large or small animals
- sngle limb lamness, rapid onset, short duration
- often Hx of laceration or surgery
- clinical exam (heat, pain, swelling on palp, joint structures may be normal,febrile)
- differentiate joint from bone
- moderate intermitent lamenss days/weeks
- hx laceration or sugery
- clinical exam (MAY BE heat, pain, swelling, pain, discharge, sinus tract, pathological fx then becoems acute)
What is metabolism of bone like? How does this impact tx of an infection?
Poor - hard to fight infection
- not very cellular
- culture bugs and choose appropriate Abx
What does bone pathology always lead to?
> bone loss (lysis)
> bone formation
(= same response to tumour/infection etc.)
Dxx for bone diseae
- Rads always
- Culture and sensitivity (when swabbing tracts, must get >2/3 up the tract before skin commensals not interfering)
- Biopsy for C+S
- radionucleatide scan (deermine high levels of bone activity)
- early intervention BS
- change based on C+S
- conider local delivery (esp gentamycin)
- surgical debridement, immobilisation and lavage
- rehabilitation of entire limb
Ddx for osteomyelitis on rads?
What tye of joint neoplasm may cause eroisin?
Synovial sarcoma - eating away at talus
Common presentation of osteosarcoma?
- old, large breed dog
- unilateral lamenss, chronic duration
- unesponsive to analgesia, excercise restriction
- pain on deep palpation of distal radius (common predilection site) and welling
Work up of potential osteosarcoma case
- clinical evaluation
- swab tracts
- Biopsy (Jamshidi, no. of planes but minimal skin incisions) definitive dx based on biopsy and culture
- staging and evaluation of prrognosis
Outline bone biopsy technique
- Jamshidi needle or Michelle trephine
- through centre of lesion (not margins)
- sample cortex and medulla
- multiple samples (same skin incision)
- cytology and cultulre
- ID landarks for pathologist (core v outside of lesion)
Are osteosarcomas common?
- cats and horses v rare
- feline TB
- calcinosis circumscripta
Decision making aspects of osteosarcoma tx?
- unremittengly painful if left aloone (analgesia wont do)
- must tx 1* successfully
- consider 2* spread (nearly all osteosarcs have micromets in the lung at time of dx)
- client communication (many people find skeletal tumour hard to understan implications)
Tx osteosarcoma? Prog?
- amputation (4mo)
- amputation + chemo (12-14mo)
- limb sparing + chemo (12-14)
- radiotx (palliative only)
- NSAIDs/bisphosphonates (pallliative only)
> >talk to owners repeatedly!
What are the potential prsentations of osteosarcomas?