Osteomyelitis Flashcards
Osteomyelitis is an infection of the bone characterised by progressive inflammatory destruction. What is the prevalence (number of new cases in a specified time frame) of osteomyelitis?
1 - 2-5 / 10,000
2 - 25-50 /10,000
3 - 250-500 / 10,000
4 - 2500-5000 / 10,000
1 - 2-5 / 10,000
- can be higher in developing countries
Which of the following is the most common cause of osteomyelitis?
1 - viral
2 - fungal
3 - bacterial
4 - protozoa
4 - protozoa
Are younger or older patients generally affected?
- both
- bimodal effects, where <20 or >70 y/o
What is the most common microorgaism that leads to osteomyelitis?
1 - Klebseilla
2 - Escherichia coli
3 - Staphylococcus aureus
4 - Clostridium difficile
3 - Staphylococcus aureus
- a grape like Gram negaitive bacteria
Which of the following is NOT typically a risk factor for oestomyelitis?
1 - diabetes
2 - male
3 - immunocomprimised
4 - IV drug user
5 - recieving haemodialysis
2 - male
Which part of a bone do microorhansism generally settle that lead to osteomyelitis?
1 - diaphysis
2 - articular cartilage
3 - epiphysis
4 - metaphysis
4 - metaphysis
- location of growth plates
- microorganism are here due to the blood flow
- microorganisms are found at the growing end of the bone
Although there are several ways in which bones can become infected causing osteomyelitis. What is the most common way the causative agent is spread?
1 - haematogenous
2 - lymph
3 - immune cells
4 - adjacent osteomyelitis
1 - haematogenous
Organise the stages of pathophysiology of osteomyelitis below:
1 - involcrum (new bone formation outside old bone)
2 - acute inflammation and venous congestion
3 - pus moves from medullary to periosteum over 2-3 days
4 - blood supply is comprimised leading the necrosis over 7 days
5 - if bone is salvagable, new bone will begin to form over 10-14 days
6 - suppuration (pus formation)
7 - pocker of dead tissue, called a sequestrum form
2 - acute inflammation and venous congestion
6 - suppuration (pus formation)
3 - pus moves from medullary to periosteum over 2-3 days
4 - blood supply is comprimised leading the necrosis over 7 days
7 - pocker of dead tissue, called a sequestrum form
5 - if bone is salvagable, new bone will begin to form over 10-14 days
1 - involcrum (new bone formation outside old bone)
In a patient undergoing dialysis, which 2 of the following bones are more commonly affected?
1 - clavicle
2 - spine
3 - ribs
4 - humerous
2 - spine
3 - ribs
In a patient who is an IV user, which 2 of the following bones are more commonly affected?
1 - clavicle
2 - spine
3 - ribs
4 - humerous
1 - clavicle
What are the 2 key symptoms a patient is likley to present with iuf they have osteomyelitis?
1 - pain at site of infection
2 - swollen joint
3 - unable to weight bear or use the joint
4 - fever (if acute)
1 - pain at site of infection
4 - fever (if acute)
All of the following are signs a clinician will be able to see if a patient has osteomyelitis, EXCEPT which on:
1 - signs of sepsis if acute
2 - erythema (red skin reaction)
3 - Tenderness
4 - Oedema
5 - Sinus tract if chronic
6 - Limited range of movement of adjacent joints
7 - crepitus at adjacent joints
7 - crepitus at adjacent joints
Osteomyelitis can present in a similiar way to other conditions. All of the following are potential differentials, which is the LEAST likely?
1 - Benign tumour
2 - Malignant tumour
3 - Healing fracture
4 - Septic arthritis
4 - Septic arthritis
An X-ray can be used to investigate a patient with suspected osteomyelitis. But is the X-ray always useful?
1 - no
- if acute, the scan can be normal for up to 2 weeks
An X-ray can be used if we suspect a patient has osteomyelitis. However, in an acute setting the x-ray can be normal for up to 2 weeks. What % of bone loss has to be present before it can be detected on X-ray?
1 - 10%
2 - 25%
3 - 50%
4 - >75%
3 - 50%
In a patient with chronic osteomyelitis we may see all of the following features, EXCEPTY which one?
1 - patchy lucency (bone is no longer white, appears darker)
2 - new periosteum bone formation
3 - sequestrum (appears radiodense compared to osteopenic surrounding
4 - fracture
4 - fracture
- sequestrum is necrotic bone that has been surrounded by granulation tissue
Which of the following is NOT a typically raised blood marker in a patient with suspected osteomyelitis?
1 - WBC
2 - CRP
3 - LFTs
4 - Erythrocyte Sedimentation Rate (ESR)
3 - LFTs
- we would need to measure LFTs, U&Es and glucose though
In a patient with suspected osteomyelitis, we need to take samples and send for all of ther following, EXCEPT which one:
1 - gram staining
2 - cell counts
3 - blood culture
4 - cell culture
5 - crystal analysis
5 - crystal analysis
- gout and pseudogout are unlikley
In a patient with osteomyelitis, which of the following is NOT part of the conservative management approach?
1 - amputate
2 - pain relief by bed rest
3 - analgesia
4 - splintage
1 - amputate
In a patient with osteomyelitis, which of the following is NOT part of the conservative management approach?
1 - amputate
2 - pain relief by bed rest
3 - analgesia
4 - splintage
Once a patient with osteomyelitis has had blood and pus cultures, which antibiotic is typically given IV to treat osteomyelitis?
1 - vancomyocin
2 - co-amoxiclav
3 - flucloxacillin
4 - penacillin
3 - flucloxacillin
- if penacillin allergy then can use clindamyacin
Once a patient with osteomyelitis has had blood and pus cultures, flucloxacillin is typically given IV to treat osteomyelitis. This is generally given at a high dose for how long?
1 - 6 hours
2 - 6 days
3 - 6 weeks
4 - 6 months
3 - 6 weeks
Which of the following is NOT typically a surgical treatment for patients who do not respond to conservative management for osteomyelitis?
1 - amputation
2 - irrigation and debridement
3 - joint replacment
3 - joint replacment
Patients with osteomyelitis are typically treated and cured., However, what is the risk of malignancy?
1 - 1%
2 - 10%
3 - 20%
4 - 50%
1 - 1%
What is the imaging of choice in osteomyelitis?
1 - CT scan
2 - X-ray
3 - MRI
4 - ultrasound
