Final - Bone Infection

Question 1

4 different types of osteomyelitis

Answer 1

Suppurative

Non-suppurative

Syphilitic

Mycotic

Question 2

High risk groups of suppurative osteomyelitis

Answer 2

IV drug users
Babies
Alcoholics
Drug Addicts
Diabetic

Question 3

M/C bacteria to cause osteomyelitis?

Answer 3

Staph. Aureus

Question 4

4 pathways of osteomyelitis infection

Answer 4

Hematogenous

Contiguous (ST to bone)

Direct implantation

Post Op (combo of direct implantation and hematogenous)

Question 5

Difference in presentation between young and old patients with osteomyelitis

Answer 5

Young: fever, malaise, signs of bacterial infection, pain and swelling at site of infection, loss of limb function, ^ ESR and WBC

Adults: more insidious onset, chronic, fever, malaise, edema, erythema, pain

Question 6

M/C age group for osteomyelitis?

Answer 6

2-12

Question 7

Bone development and epiphyseal blood supply

Answer 7

Infant: no vascular barrier at growth plate until 8 months

Child: Physis acts as barrier to vasculature

Adult: Physis ossified and is no longer a barrier vasculature (can lead to septic arthritis because infection can spread to epiphysis)

Question 8

Pathophysiology of osteomyelitis

Answer 8

Bacteria get into medullary tissue

Question 9

What causes lytic destruction in osteomyelitis?

Answer 9

Immune system as it tries to kill the bacteria

Question 10

What is a sequestrum? Involucum? Cloaca?

Answer 10

Sequestrum: dead, necrotic bone tissue

Involucum: new bony collar formation

Cloaca: Drainage sinus formed in bone d/t infx

Question 11

Complications of osteomyelitis?

Answer 11

Can become chronic
Metastatic infection
Angular bone deformation (occurs when one part of the physis prematurely ossifies)
Pathological fracture
Bacteremia, septicemia
ST infection and persistent sinuses

Question 12

Radiologic features of osteomyelitis? Acute vs chronic?

Answer 12

Can be hard to distinguish between osteosarcoma/Ewing’s sarcoma

Signs of osteomyelitis: throughout bone, lamellated periosteal response, sequestrum and involucum (if present)

Chronic has much more sclerosis and will have sequestrum, involucrum, and possibly cloaca

Question 13

Osteomyelitis in the spine, child vs adult

Answer 13

With child (>20yo) usually starts in disc, in adult starts in anterior vertebral end plate

Question 14

Pertinent Hx that may indicate spinal infection? PE fx?

Answer 14

Recent trauma, infection, surgery, insidious onset

Warmth/rubor over vertebra, can’t recreate CC pain

Question 15

Radiographic findings of osteomyelitis of the spine of kids

Answer 15

Abrupt change in disc space

Question 16

Tx and prognosis of osteomyelitis

Answer 16

The earlier the Dx and Tx the better the prognosis

Surgical drainage and debridement with PROLONGED antibiotic therapy

Question 17

What is Brodie’s Abscess? Sx?

Answer 17

Localized osteomyelitis

Local pain that is worse at night and relieved by aspirin (DDx OO)

Question 18

Brodie’s Abscess radiographic findings

Answer 18

Oval lytic lesion with some sclerosis around border, usually in the metaphysis of long bones

Question 19

T or F: septic arthritis is m/c polyarticular

Answer 19

False AF

Monoarticular

Question 20

M/C age group for septic arthritis?

Answer 20

<30 yo

Question 21

Sx of septic arthritis?

Answer 21

One joint that is warm, has limited ROM and is painful. Systemic signs of infection.

Question 22

How do you diagnose septic arthritis?

Answer 22

With joint aspiration to identify presence of pathogen

Question 23

T or F: Septic arthritis progresses very rapidly

Answer 23

True AF

Question 24

Clinical picture of septic arthritis? (3 parts)

Answer 24

1. Fever, malaise,
2. Painful swelling in one joint (usually)
3. Signs of inflammation

Question 25

What are the two most common sites of septic arthritis?

Answer 25

Knee and hip

Question 26

ST finding in septic arthritis?

Answer 26

Joint distension

Fat pad displacement

Question 27

What is a late sequela of septic arthritis?

Answer 27

Osseous or fibrous ankylosis

Question 28

If patient has acute symptoms and signs of DJD, whats at the top of your DDx list?

Answer 28

Infection, not just DJD

Question 29

M/C location where nonsuppurative osteomyelitis spreads from?

Answer 29

Lungs

Question 30

M/C location for nonsup osteomyelitis?

Answer 30

Thoracic and lumbar

Question 31

T or F: nonsup osteomyelitis is most common in 25 year olds

Answer 31

False

Most common in people who have immunodeficiency (children, elderly, AIDS, alcoholic, drug abuser, serious illness)

Requires “massive” exposure

Question 32

M/C cause of nonsup osteomyelitis?

Answer 32

TB

Question 33

Si/sx of skeletal TB

Answer 33

Insidious onset
Few systemic signs
Mild pain
Appendicular

Question 34

What is Pott’s disease? M/C location? Earliest radiographic sign? How does it affect ST?

Answer 34

Tubercular spondylitis
25-60% of skeletal TB

Lower Thx upper Lx

Disc space loss

Paravertebral soft tissue mass (often calcification)

Question 35

Radiographic findings for Tubercular Arthritis

Answer 35

Phemister’s traid

1. Progressive joint space narrowing
2. Juxtaarticular osteopenia/porosis
3. Peripheral erosive defects

Fibrous ankylosis at end stage (osseous is rare)

Question 36

Latent radiographic period for osteomyelitis of the extremity is what? For spine?

Answer 36

10 days

3 weeks

Question 37

The earliest radiographic changes in bone and joint infection are first seen where?

Answer 37

ST (elevation of fat planes and blurring of fat muscle interface)