Fibrous Xanthomas and Paget's

Question 1

What conditions make up the group of fibrous xanthomas in order from smallest to largest?

Answer 1

Fibrous cortical defect, nonossifying fibroma, fibrous dysplasia

Question 2

What is unique about the specific placement of a fibrous cortical defect in bone?

Answer 2

Loves cortex

Question 3

What other lesion loves the cortex of bone like a fibrous cortical defect?

Answer 3

Osteoid osteoma

Question 4

What is the treatment for a fibrous cortical defect or nonossifying fibroma?

Answer 4

Nothing because they usually regress over a 2-5 year period

Question 5

How does a fibrous cortical defect look different than an osteoid osteoma?

Answer 5

No nidus or cortical thickening with FCD

Question 6

What is the age range for a nonossifying fibroma?

Answer 6

8-20 years old (most occur in second decade aka teens)

Question 7

How common are nonossifying fibromas?

Answer 7

30-40% of children

Question 8

What is the specific part of bone where we find nonossifying fibromas?

Answer 8

Eccentric and metadiaphyseal

Question 9

What are the common locations for nonossifying fibromas?

Answer 9

Long bones of lower extremity like distal tibia and distal femur

Question 10

Why are fractures more possible with a nonossifying fibroma compared to a FCD?

Answer 10

Larger than a FCD (same with fibrous dysplasia)

Question 11

What is the age range for fibrous dysplasia?

Answer 11

1-2 decades of life

Question 12

Is fibrous dysplasia most commonly monostotic or polyostotic?

Answer 12

Monostotic (involving one bone)

Question 13

Polyostotic fibrous dysplasia is seen with what type of condition that is also associated with Coast of Maine cafe au lai spots and precocious puberty in females?

Answer 13

McCune-Albright Syndrome

Question 14

What radiographic finding is associated with fibrous dysplasia?

Answer 14

Rind sign

Question 15

What is the term for the area of thickened sclerosis along the rim of a lesion of fibrous dysplasia?

Answer 15

Rind sign

Question 16

What appearance occurs with the internal matrix involving fibrous dysplasia?

Answer 16

“Ground glass” appearance

Question 17

What deformities can arise in the femur/tibia from fibrous dysplasia?

Answer 17

Saber shin and/or shepard’s crook deformities

Question 18

How common is Paget’s disease?

Answer 18

3% of population over 40 years old

Question 19

In what area of the world is Paget’s more common?

Answer 19

Norther latitudes and specifically UK, Australia, New Zealand

Question 20

What is the age range for Paget’s?

Answer 20

Over 60

Question 21

What is thought to be the cause of Paget’s?

Answer 21

Virus

Question 22

How does bone change overall from Paget’s disease?

Answer 22

Increased resorption followed by increased bone formation which has a disorganized trabecular pattern lending to bone softening (bone increases in size and gets very white)

Question 23

What are some of the more common areas for Paget’s?

Answer 23

Pelvis, lumbar/thoracic spine, proximal femur, calvarium..

Question 24

What are the lab findings seen with Paget’s?

Answer 24

Increased hydroxyproline and alkaline phosphatase with normal serum calcium and phosphorus levels

Question 25

"Cotton wool" appearance is associated with what lesion?

Answer 25

Paget's (in path we called it the "fuzzy pelvis")

Question 26

What are the 4 stages of Paget's disease?

Answer 26

1 lytic/destructive 2 mixed 3 sclerotic/ivory 4 malignant degeneration and possible change to osteosarcoma

Question 27

Paget's disease can lead to what serious change in the skull?

Answer 27

Basilar invagination with foraminal encroachment (due to bone softening)

Question 28

What is the term for the well defined lysis of the frontal and occipital regions?

Answer 28

Osteoporosis circumscripta

Question 29

What are the initial patient symptoms with Paget's?

Answer 29

None really...except maybe hats are feeling tighter (due to cortical thickening)

Question 30

At what specific part of bone does Paget's begin in in long bones?

Answer 30

Subarticular end of bone (diff dx with GCT and chondroblastoma)

Question 31

What is the radiographic sign is a lucent leading edge in a long bone seen during the lytic phase of Paget disease of bone?

Answer 31

Candle flame or blade of grass sign

Question 32

2-9% of the time, Paget's can become malignant into what type of lesion?

Answer 32

Osteosarcoma

Question 33

What is the radiographic sign when there is thickening of the iliopectineal line and cortical lines of the pubic bones?

Answer 33

Rim sign

Question 34

Paget's disease can also cause what kind of issue with the femur heads?

Answer 34

Acetabular protrusion

Question 35

What radiographic signs can be seen in a vertebral body from Paget's?

Answer 35

Picture frame vertebra and ivory vertebra

Question 36

What are the 3 differentials for an ivory vertebra?

Answer 36

Hodgkins (20-40 YOA), blastic mets (over 40 YOA), Paget's (over 60 YOA)

Question 37

What are some possible complication of Paget's?

Answer 37

Peripheral nerve or brainstem compression with spinal stenosis, hearing loss, blindness, facial palsy, hyperemia of overlying skin, high output cardiac failure, DJD

Question 38

What is the name of the horizontal jagged fracture sometimes seen in the long bones with Paget's?

Answer 38

Banana fractures