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Flashcards in Osteomyelitis Deck (15)
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1
Q

OSteomyelitis

A

Infectious or non-infectious

We talk about infections

Progressive destruction of bone and formation of sequestra

Inflammation of bone and/or bone marrow space

2
Q

Etiology and microbiology

A

Hematogenous…extension from soft-tissue infection…direct inoculation into bone

Staph aureus is the most common organism overall

3
Q

Children vs. adults

A

Children - acute hematogenous…better overall prognosis due to blood uspply and actively remoduling bone

Adults - contigous spread or direct inoculation…more chronic…more often ofreign bodies…more difficult to tx

4
Q

Acute hematogenous osteomyelitis

A

Mostly in infants or children or IV drug abuses

Most often in metaphysis of long bones (distal femur and proximal tibia)

Often preceded by minor trauma

5
Q

Micro bio of acute hematogenous

A

Staph is most common

Group A, pneumocossu, group B (neonates)

Kingella kingae - younger with stomatitis

Salmonella - sickle cell

Heamophilus - uncommon)

Other more in IV drug abusers - E coli, Candida, pseudomonoas

6
Q

Acute hematogenous presentation and untreated

A

Localized, point tenderness, transient fever, maybe swelling

Spread into epiphysis and joint space

Subperiosteal abscess between periosteum and bone

Brodie’s abscess - localized bone abscess

Bone necrosis and formation of sequestra

7
Q

Tx of acute hematogenous osteomyelitis

A

Drainage
Debridement of sequestra

Anti biotics

Children - at staph auerus and gram -…4-6 weeks and switch to oral

Adults - staph aureus…if IVDA, then add gram neg…more often parenteral through entire course

Narrow based on culture results

8
Q

Osteomyelitis due to local extension or direct incoulation

A

Diabetic foot ulcer, decubitus ulcer, cellulitis or myosistis

Contaminted open fracture…depends on level of contamination (think dirt bike vs. car)

Nosocomial infection of operative site

9
Q

MIcrobio of local or direct inoculation

A

More likely to be poly than hematogenous

MRSA most common

Nosocomial - Staph epidermidis and other skin flora…pseudomonas and other gram negs

Open fracture - MRSA, aerobic gram-neg bacilli (like E coil, enterbacter, psudomonas), enterococcus, anaerobes )think soil), fungi

10
Q

Presentation of local or direct inoculation

A

Often present iwth inadequate response to therapy for SSTI or return of sx

Drainage from surgical site if nosocomial

contaminated open fracutre may not become apparent until several months after injury…non-union of fracture, sinus tract formation, dehiscence

May also have fever other systemic sx

11
Q

Tx of local or direct incoluation

A

Surfical drainage nad removal of foreign bodies

Debridement of non-viable bone or sequestra

Soft tissue debridement

ABs - direct at staph areus but combine broad spectrum is contaminated open fracutrs and nosocomial infecion

4-6 week minimum

12
Q

Chronci osteomyelitis

A

Un-treated actue

Lacks systemic sx

May need debridement to cure

Need 6 mos or more of ABs

May need chronic suppressive ABs

13
Q

Vertebral osteomyelitis

A

More often hematogenous
IVDU

Staph aureus or coag neg staphyloccci
Gram-negs - pseudomonas
Candida
Myco TB

14
Q

Workup and dx of osteomyellitis

A

Inflam markers signiciantly elevated during acute osteomyelitis but not during chronic

Blood cultures more likely in acute

Culture of bone/abscesss material is best but may be neg in chronic

Gram stain and cblood culture Kingella)

15
Q

Radiological

A

Plan film - lytic lesions, periostea lelevation, periosteal new bone formation…10-14 days after

MRI - most sensitive
Low marrow intesntiy on T1..bright on T2
Periosteal elevation/abscess
Enahnement and abscess formation (with gadolinium)

Imaging modaliyt of choice

Bone scan - better sensitivity than plain but les than MRI…less specific
Low resolution
Helpful if multifocal suspected
incrreased uptake in areas of increased bone turnover