OSTEONECROSIS AND OSTEOCHONDROSIS

Question 1

Osteonecrosis: Defined as

Answer 1

death of the osseous cellular components and marrow of bone d/t inadequate blood supply

Question 2

M/C hematologic condition of bone

Answer 2

Osteonecrosis

Question 3

What is the AKA for Osteonecrosis

Answer 3

Ischemic necrosis,
aseptic necrosis,
avascular necrosis,
bone infarction

Question 4

What is the first and second MC avascular necrosis site involved in osteonecrosis?

Answer 4

MC Femoral head

2nd MC Humeral head

Question 5

Osteonecrosis bone infarct occurs where

Answer 5

Metaphseal or

Diaphyseal

Question 6

What term is used when osteonecrosis is in the bone end or juxta-articular involvement?
What is the MC location?

Answer 6

Avascular necrosis

Femoral head, 2nd mc is humeral head

Question 7

The term Bone infarct is used when osteonecrosis is in what part of the bone?

Answer 7

Metaphyseal or Diaphyseal

Question 8

What is the latent period for symptoms to develop in osteonecrosis?

Answer 8

a few weeks to 1 year

Question 9

Name the 4 mechanisms of infarction

Answer 9

Intraluminal obstruction
Arterial wall disease
Vascular compression
Physical disruption of vessel

Question 10

A temporary loss of blood flow can lead to

Answer 10

bone ischemia

Question 11

A prolonged decrease in blood flow can lead to

Answer 11

Bone infarction

Question 12

What are the more common causes (predispose) of osteonecrosis?

Answer 12

Vascular, Drugs, Congenital, Trauma
Infection, Inflammatory, Autoimmune, Endocrine
Spontaneous

Question 13

Osteonecrosis vascular cause is associated with

Answer 13

Hemoglobinopathies

Question 14

What OSTEONECROSIS: cause is associated with Infections?

Answer 14

Septic emboli

Question 15

What OSTEONECROSIS: cause is associated with Drugs/Toxins?

Answer 15

Alchololism and steroids

Question 16

What OSTEONECROSIS: cause is associated with inflammation?

Answer 16

Pancreatitis

Question 17

What OSTEONECROSIS: cause is associated with congenital disorders/diseases?

Answer 17

Gaucher’s disease

Question 18

What OSTEONECROSIS: cause is associated with autoimmune disease?

Answer 18

SLE and RA

Question 19

What OSTEONECROSIS: cause is associated with Trauma?

Answer 19

Radiation
Fractures*
Dysbarism

Question 20

What OSTEONECROSIS: cause is associated with the endocrine system?

Answer 20

Cushing’s disease

Question 21

What OSTEONECROSIS: cause is knowns as an additional non-specific cause?

Answer 21

Spontaneous*

Question 22

Metaphyseal-Diaphyseal infarctions Central area of necrosis is surrounded by what?

Answer 22

ischemic and healing tissue

Question 23

Most common location of metaphyseal/diaphyseal infarction from greatest to least is

Answer 23

Distal femure, proximal tibia and proximal humerus

Question 24

What are some clinical indications of a serious underlying problem?

Answer 24

Diabetes, Alcoholism, Chronic renal disease

Question 25

Osteonecrotic meta/di-aphyseal infarcts may be

Answer 25

cortical or medullary

Question 26

Osteonecrosis infarcts are usually what?

Answer 26

Asymptomatic

Question 27

Radiographically, osteonecrotic infarct are first seen as a area of what? What type of calcifications are seen on the rim? Internally, the area may look like

Answer 27

rarefaction Undulating or sepiginous sclerosis/calcifications

Question 28

What radiographic feature can be observed in the bone?

Answer 28

Split cortex, periosteal response

Question 29

What does the bone look like on a radiographic film?

Answer 29

small tubular bones

Question 30

What is the MC cause of osteonecrosis is associated with trauma?

Answer 30

Fractures

Question 31

What MC drugs/toxins cause of osteonecrosis?

Answer 31

Alcoholism and steroids

Question 32

What is the preferred source of imaging used to detect osteonecrosis infarct?

Answer 32

MRI | 2nd best is Bone scintigraphy

Question 33

With metaphyseal diaphyseal infarct its radiographic feature is usually? An osteopenia is an area of osteonecrosis infarct radiographic feature?

Answer 33

Medullary and central | area of rarefaction

Question 34

Cortical infarctions are usually seen in who? | In what location?

Answer 34

Young patients with SC | small tubular bones

Question 35

What are the two most common skeletal locations for osteonecrosis?

Answer 35

Femoral head, Humeral head

Question 36

What are two DDX for metaphyseal diaphyseal infarction? Lesions in this area are usually what?

Answer 36

enchondroma and low-grade chondrosarcoma | Elongated

Question 37

What radiographic finding is pathognomonic of avascular necrosis?

Answer 37

Crescent sign

Question 38

Avascular necrosis usually begins in what region of the femoral head?

Answer 38

Anterior superior

Question 39

What imaging procedure is most sensitive for the early detection of osteonecrosis?

Answer 39

MRI

Question 40

What are the four mechanisms of infarction?

Answer 40

intraluminal obstruction, Arterial wall disease, Vascular compression, Physical disruption of vessel