Infection SKEL B

Question 1

Osteomyelitis definition:

Answer 1

Infection of bone and bone marrow

Question 2

3 categories of Osteomyelitis

Answer 2

Acute - developing w/in 2 weeks of disease onset

Subacute - developing w/in one to several months

Chronic - developing after several months

Question 3

90% of Suppurative Osteomyelitis is due to ___________ _____________

Answer 3

Staphylococcus Aureus

Question 4

Typical Non-suppurative Osteomyelitis typically involves what organism?

Answer 4

Mycobacterium tuberculosis

Question 5

Syphilitic (LUES) congenital/acquired osteomyelitis typically involves what organism?

Answer 5

Treponema pallidum

Question 6

List 4 principle mechanisms of osseous and articular contamination.

Answer 6

1. Hematogenous. - Via bloodstream
2. Spread from a contiguous source - cutaneous, sinus and dental infections
3. Direct Implantation - penetrating injuries (usually feet)
4. Postoperative infection. - contamination of surgical sites

Question 7

MC age group of Osteomyelitis

Answer 7

2-12 years old

Question 8

Gender Ratio of Osteomyelitis?

Answer 8

3:1 Male

Question 9

MC sites of Osteomyelitis?

Answer 9

Large tubular bones: femur, tibia, humerus, and radius most often

Question 10

Late Stage patients with Osteomyelitis will typically reveal involucrum, cloaca, and sequestra on plain-film radiographs. What do these words mean?

Answer 10

Involucrum - A thick sheath of periosteal new bone around a sequestrum. (Periosteal Rx) “bony Collar” continuation of periosteal response. Will eventually represent the new periosteum.

Cloaca - the draining sinus (the occurrence of a defect that may develop in the involucrum)YR 1375

Sequestra - Segments of necrotic bone separated from living bone by granulation tissue. Chalky, white area representing dead bone

Question 11

Found in chronic Osteomyelitis, what radiographic sign may be present after 20-30 years with chronic disease, a rare, but significant complication of the draining sinus.

Answer 11

Marjolin’s Ulcer - epidermoid carcinoma occurring at a sinus tract

Question 12

Brodie’s Abscess, a low-grade infection usually seen in children, may mimic _______________.

Answer 12

Osteoid Osteoma

Question 13

what percent of skeletal infectious disease with involve the spine?

Answer 13

10%

Question 14

Definition of Tom Smith Arthritis:

Answer 14

The spread of metaphyseal osteomyelitis to the adjacent joint when the metaphysis is intracapsular.

I.e. proximal/distal femur and humerus
Distal tibia

Question 15

Septic Arthritis Definition

Answer 15

Infection of joint (synovial tissue, articular surfaces)

Question 16

Osteitis Definition

Answer 16

Inflammatory condition usually confined to cortex

Question 17

Suppurative Osteomyelitis definition

Answer 17

Bone marrow infection by (pyogenic) non-tubercular organism

Staph. Aureus
Strep. Pneumoniae
E. Coli
Pseudomonas

Question 18

The latent (hidden) stage of Suppurative OM lasts how long?

Answer 18

1-10 days

Question 19

How long and what findings occur radiographically with the early stage of Suppurative OM?

Answer 19

Days 10-21,

Decreased bone density + soft tissue

Question 20

The middle stage radiographically associated with a patient who has had Suppurative OM for weeks would show __________ + __________________.

Answer 20

Moth-eaten destruction + periosteal reaction

Question 21

Septic Arthritis is most common in joints in which _______________.

Answer 21

The capsule covers metaphysis

Question 22

In a pediatric patient with loss of disc space we think _________. Never ___________.

Answer 22

Infection!, never DDD Degenerative disc disease

Question 23

The most common cause of infection-related death worldwide?

Answer 23

Tuberculosis

King of disease (very prevalent)
Disease of kings (no one spared)

Question 24

Clinical Features of Non-Suppurative OM?

Answer 24

Respiratory symptoms
weight loss
Night sweats
Vague joint/ back pain
Persistently elevated ESR Erythrocyte Sedimentation Rate

Question 25

TB Septic Arthritis PHEMISTER’S TRIAD:

Answer 25

Juxtarticular osteporosis
Marginal erosions
Slow joint space loss

Question 26

Radiographic feautures of TB, Non-Suppurative OM:

Answer 26

Similar to OM in the spine but add:

Multiple Levels

Paraspinal cold abscesses with Ca+