Avascular Necrosis (AVN)

Question 1

Osteochondroses

o There are a variety of terms that fall into this category.
This is a ‘garbage can’ term for irregularity of the growth
centers in _________.
o Osteochondrosis – non-vascular etiology, e_______only

o Osteochondrosis, ischemic necrosis, avascular necrosis –
vascular etiology, can occur in __________

• Causes are spontaneous (MC), trauma, alcoholism, cotico-
  ________, hemoglobinopathies, SLE, Cushing’s, and r______.

Define Infarction – non-epiphyseal v_______ e_____

Answer 1

children

epiphyseal

adults
steroids
radiation

vascular etiology

Question 2

4 Phases of AVN

Answer 2

Avascular Phase
Revascularization Phase
Repair Phase
Deformity Phase

Question 3

Name the correct phase

neovascularity, subchondral fracture, bone resorption

normal bone, with permanent residual deformity (amount depends on site and success of treatment)

loss of blood supply, bone death, synovitis, hyperemia

new bone deposition, reduction in osteoclastic activity

Note —> Complete healing takes 2-8 years

Answer 3

Revascularization
Deformity
Avascular
Repair

Question 4

Osteonecrosis: IMAGING PROTOCOLS

o ________ film usually done first to look for obvious
changes
Note this type is Insensitive unless there is 30-50% change

o Scintigraphy is very sensitive but ___ (3-5% change)
o ____ is best. Very sensitive and relatively specific
(2-3% change)

Answer 4

Plain
Non Specific
MRI is best and very sensitive and relatively specific

Question 5

Osteonecrosis: LEGG-CALVE-PERTHES (LCP)

Affects what?
Affects who? Peak age? May complain of what mostly?

Answer 5

Femoral head
Affects males mostly and peak age is 3-12 y.o.
Knee pain

Note: Avascular necrosis is predisposed by loss of collateral blood supply to femoral head during ages 4-7

Question 6

Radiological Findings for (LCP)
Capsular distention, joint space widening ______

 Undergrowth of epiphysis, f_____and f_____, solid or
patchy sclerosis, lucent crescent sign, widened femoral
neck
 Gradual reconstitution of normal bone density and shape
 Varying degrees of deformity (enlarged head, flattened head, coxa vara)
 Scintgraphy shows ______ spot early
 MRI shows ______ loss of marrow signal with signs of joint e_______

Answer 6

Laterally
Flattening and Fragmentation
Cold
Focal …… Effusion

Question 7

Osteonecrosis: FREIBERG’S

o Affects the _________ heads, especially the _____
o Affects __________, 13-18 peak age
o Usually _______to trauma
o Appears as a f—-, i—–, s—- head

Answer 7

metatarsal heads; 2nd
MC affects Females age 13-18
Secondary
flattened, irregular, sclerotic head

Question 8

Panner’s Disease

o Progressive radiolucency of the _______ with eventual
_________

Answer 8

capitellum

fragmentation

Question 9

Osteonecrosis: KEINBOCH’S
o Affects what? 
o Peak age = \_\_to \_\_\_
o Usually secondary to trauma or \_\_\_\_\_\_\_ use
o See C-----, S------, F------

Answer 9

the lunate
20-40
excessive use
Collapse, Sclerosis and Fragmentation

Question 10

Osteonecrosis: KOHLER’S

o Affects what?
o Affects MALES MC, around age what?
o Sclerotic and flattened bone
o Can mimic normal growth variation

Answer 10

tarsal navicular
5

NOTE: Other Osteonecroses: A variety of other bones can be affected, such as the talus, humerus, and scaphoid

Question 11

What are the TWO Trauma-Related Osteochondroses

Answer 11

Osgood-Schlatter’s

Scheuermann’s aka(idiopathic spondylodystrophy

Question 12

o Osgood-Schlatter’s
 Affects what?

 Traction _______ from overuse

 This Is a clinical diagnosis

 Radiographically, can see fragmentation of the tibial
tuberosity apophysis, with overlying soft tissue ______

 Affects MALES MC, ages 11 to ____

Answer 12

the tibial tuberosity
apophysitis
inflammation
15

Question 13

Scheuermann’s (idiopathic spondylodystrophy)

 Affects what and where in the spine

The Cause is over stress of spine at young age, especially
in _________

 Peak age 13-____

See multiple ______ nodes, endplate irregularities, anterior wedging of vertebral bodies, and increased _______
 Changes should occur at at least ____ levels

Answer 13

endplates especially in the thoracic spine

athletes

17

Schmorl’s

Kyphosis

3

Question 14

Osteochond. Dissecans (MIsc. Osteochondrosis)

May be avascular necrosis of _______ bone or post-traumatic fragmentation

 Affects Who, peak age = ____ -20 years
 MC locations are knee (f______ condyle) (F.A.K.E.)
 Look for _____ ______ in joint, with articular surface defect

MRI is excellent for determining integrity of _____ cartilage

Answer 14

subchondral bone

affects males 11-20 y.o

Knee (Femoral condyle), ANKLE AND ELBOW

LOOSE BODY

hyaline

Question 15

Sever’s Disease

Not a true disease

 Radiographically (clinical condition may still be real)
 Normal variation of growth
 ________ apophysis is sclerotic and fragmented.

Answer 15

Calcaneal

Question 16

Infarctions

 Necrosis in the ________ compartment of the metaphysis and/or diaphysis.

 Due to a variety of underlying diseases, or may be spontaneous
 Appears as a region of serpiginous calcification similar to e______

Answer 16

medullary

enchondromas

Question 17

Radiation Necrosis
 Due to oral ingestion, intravascular injection, surgical implantation, or external _____________

 Look for sclerotic and irregular regions of bone that are confined to a ____-_____ region.

 Changes usually seen ___ months after initial insult.

 When seen in children, may see _______ _________

Answer 17

Radiation

well-defined

3

growth disturbances

Question 18

Kummel’s Disease

 Avascular necrosis of what?.
 Successfully treated by what?

Answer 18

vertebral body.

vertebroplasty.