bone & joint infections Flashcards
acute osteomyelitis is more common in?
children (boys>girls)
history of trauma could determine its site
How is the blood stream invaded in osteomyelitis?
infants: infected umbilical cord
adults: urrethral catheter, arterial lines
boils
tonsilities
skin abrasions
dirty needles
What are the organisms that could cause osteomyelitis?
- STAPH. AUREUS
- strep pyogens
- strep. pneumonie
- H. influenza
- E. coli
- pseudomonas auriginosa
- proteus mirabilis
how does osteomyelitis progress?
infection at METAPHYSIS —> vascular stasis favours bacterial colonization —-> inflammation —> suppuration —-> bone necrosis —> reactive new bone formation —> resolution
if a patient presents to you in severe pain, fever, malaise, is reluctant to move, and has signs of toxemia, what will be your provisional diagnosis?
osteomyelitis
What are the clinical features of osteomyelitis in infants?
- failure to thrive
- drowsy
- irritable
- metaphyseal tenderness
- decreased range of motion (common around knees)
What are the clinical features of osteomyelitis in adults?
- fever
- backache
- history of UTI following urological procedure
- history of diabetes or immunosuppression (thoracolumbar spine)
What are the diagnostic tools used to diagnose osteomyeitis?
- history & examination
- CRP & ESR are the parameters for joint infection
- x-ray will be normal in the first 10-14 days
- Gallium 67 will clearly show infection
- aspiration if its huge and can be aspirated
what is the differential diagnosis of osteomyelitits?
- cellulitis
- acute septic arthritis
- acute rheumatism
- sickle cell crisis
- Gaucher’s disease
How should osteomyelitis be treated?
- supportive treatment for pain & dehydration
- splintage
- antibiotics if acute
- surgery for subacute & chronic
complications of acute osteomyelitis?
- septicemia
- metastatic infection
- septic arthritis
- altered bone growth
- chronic osteomyelitis
subacute osteomyelitis usually occurs in?
immunocompromised patients
brodies abscess is found in which bone infection?
SUBACUTE OSTEOMYELITIS
- has a rigid cortex
- local tenderness
- limp & slight swelling
- pain for several weeks or months
What are the investigation done for subacute osteomyelitis?
- x ray
- bone scan
- biopsy (grow organism)
How should subacute osteomyelitis be treated?
- antibiotics for 6 months
- surgery
which bone infection frquently follows open fractures or operations?
chronic osteomyelitis
What organisms cause chronic osteomyelitis?
usually a mixed infection due to open fractures
- Staph. aureus
- E. coli
- strep. pyogens
- proteus mirabalis
What is the pathogenesis of chronic osteomyelitis?
destruction of bone —> cavities containing pus & pieces of dead bone (sequestra) —> chronic reactive new bone takes form of involucrum
What is the histological picture of chronic osteomyelitis?
chronic inflammation
How should chronic osteomyelitis be treated?
antibiotic (4-6 weeks) surgery - sequestrectomy - muscle flap - double lumen tube - ilizarov fixation
What are the other types of osteomyelitis?
post-operative osteomyelitis - early (within 3 months) - late Sclerosing osteomyelitis - non-suppurative
What are the routes of infection in acute septic arthritis?
- direct invasion
- penetrating wound
- intra-articular injection
- arthroscopy
- eruption of bone abscess
- haematogenous
What organisms cause acute septic arthritis?
- STAPH. AUREUS
- strep. pyogens
- H. influenza
- E. coli
What is the pathology of acute septic arthritis?
acute synovitis with purulent joint effusion —> articular cartilage attacked by bacterial toxin & cellular enzyme —> complete destruction of articular cartilage
sequelae of acute septic arthritis?
- complete recovery
- partial loss of articular cartilage
- fibrous or bony ankylosis
acute septic arthritis in neonates resembles what?
septicemia
- irritability
- resistant to movement
acute pain in a single large joint affects who?
Children in acute septic arthritis
- reluctant to move the joint
- increase in temp & pulse
- increase tenderness
Which joints are affected in adults in case of acute septic arthritis?
- superficial joints (knee, ankle, wrist)
What is the most important investigation in acute septic arthritis?
ASPIRATION
- if there is thick yellow pus prepare the OR
What are the DD for acute septic arthritis?
- acute osteomyelitis
- trauma
- gout
- irritable joint
- hemophilia
- rheumatic fever
- Gaucher’s disease
How should acute septic arthritis be treated?
- general supportive measures
- antibiotics
- surgical drainage
