W5 ADI

What is Pagets disease also called?

Osteitis deformans

In simple terms, what is pagets disease?

A bone softening disorder

Fill in the gap. Pagets disease is a “x” of bone diseases, along with fibrous dysplasia?

Great imitator

What are the possible theories behind the cause of Pagets disease?

• Inflammatory

• endocrine

• autoimmune

• inborn error of connective tissue metabolism

• vascular

• metabolic

• neoplastic

• chronic viral infection (measles like virus- most current theory)

What is the M:F predominance of Pagets disease?

2:1 Male

What is the common age to get pagets disease? When is it rare before?

After 55 years, rare before 40 years

Are most patients asymptomatic or symptomatic in Pagets disease?

Asymptomatic, 90%

What may pain in Pagets disease be associated with?

Bowing deformities or fractures

Fill in the gaps. An increasing “x” size is common because enlargement of the '‘x”.

hat size

calvaria

The most common affected bones in Pagets disease are what?

Pelvis

vertebrae

clavicle

humerus

ribs

What bone is the least likely to be involved in Pagets disease?

Fibula

What is the characteristic location of Pagets disease within the bone? Where does it usually extend into?

Subarticular location

Usually extends into the diaphysis

What signs does deformation of the bone in Pagets disease cause?

• shepards crook deformity of the proximal femur (coxa vara)

• Saber shin deformity (anterior tibial bowing)

• Protrusio acetabuli

• Leontiasis ossea

• Frontal and parietal bossing

• Basilar invagination

What two pathological fractures are common in Pagets disease?

• Vertebral body fracture

• transverse banana like fracture of long bones

What do psuedo-fractures in Pagets disease represent?

Local areas of demineralisation within the bone, which are replaced by fibrous tissue

In Pagets disease, what would bony expansion of a vertebra cause, and what would this lead to?

Spinal stenosis, lead to compressive neuropathy

In Pagets disease, what can occur as a result of fibrous tissue replacing bone marrow?

Anaemia

What does Pagets coxopathy represent?

Articular cartilage destruction with secondary degenerative changes

What complications seen with Pagets disease?

• Ureteric colic (stones) secondary to hypercalcemia and hypercalcuria leading to urinary calculus formation especially in immobilised patients

• High output cardiac failure

• malignant degeneration, development may be noticed when patient with known Pagets disease has localised pain

• Osteosarcoma most common tumour to complicate pagets disease (50% lytic, 25% sclerotic, 25% mixed, Tx radiation therapy, surgical resection, 5-year survival rate poor)

What are the common locations of complicated Pagets disease? What is the one rare location (few reported cases)?

• femur

• humerus

• innominate

• skull

• tibia

What laboratory findings are there in Pagets disease?

• enhanced destruction of bone collagen→ increase in urinary excretion of hydroxyproline

• increase in alkaline phosphatase

• Hypercalcemia

What is the mosaic structure of Pagets disease?

The patternless replacement of normal bone by pagetic, vascular and fibrotic bone

What are treatment options for Pagets disease?

• osteoporosis drugs (bisphosphonates)

• If bisphosphonates produces pain, Calcitonin used

In Pagets disease, what radiologic features will you see on a bone scan?

Lesions will be hot

In Pagets disease, what radiologic features will you see in the skull at both the early and advanced stage?

• Early skull lesions showing lytic stage of osteoporosis circumscripta

• Advanced stage will cotton wool appearance due to multiple radiopacites

In Pagets disease, what radiologic features will you see in the spine?

• Thickened and enlarged vertebral endplate

• Squared-off picture frame vertebra (occurs in biphasic stage)

• Ivory vertebra

In Pagets disease, what radiologic features will you see in the pelvis?

• cortical thickening

• bone expansion

• thickening of the iliopectineal line, obliterating Kohlers teardrop (rim/brim sign)

In Pagets disease, what radiologic features will you see in the long bones?

• Tibia second most common site of lytic pagets disease

• Radiolucent changes begin in subarticular end of proximal tibia, going down shaft in Candle flame appearance (blade of grass appearance)

What are the 4 stages of Pagets disease, and what is commonly seen in these stages?

Osteolytic

• Skull, tibia

Mixed

• Both lytic and blastic

• Cotton wool skull

Blastic

• Ivory vertebrae

Malignant

• Pagets sarcoma

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Skull

• Osteoporosis circumscripta

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Skull

• Osteoporosis circumscripta

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Skull

• Osteoporosis circumscripta

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Tibia

• Blade of grass appearance

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Skull

• Cotton wool skull

• inner and outer table of skull affected by this

What tumour like disorder is this and where is it?

Pagets disease

Pelvis

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Pelvis

• Note Kohlers teardrop

• Cortical thickening

• Accenuation of trabecular pattern

• Subchondral involvement

• Psuedofractures

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Pelvis and sacrum

• Note dysplastic arch with possible spina bifida

• Hint of bone softening at superior end of pelvic inlet

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Pelvis

• Gross distortion of acetabulum

• Blue lines show Kohlers lines

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Pelvis

• Pathological fracture

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Vertebra

• Picture frame vertebra

• Increased density

• Thickened endplates

• Thickened/coarsened trabecular pattern

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Vertebra

• Picture frame vertebra

• Ivory vertebra

What tumour like disorder is this, where is it?

Pagets disease

Occiput and C2

What tumour like disorder is this, where is it, what can be seen?

Pagets disease

Vertebra

• Cotton wool appearance

What tumour like disorder is this, where is it?

Pagets disease

Clavicle

What tumour like disorder is this, what can be seen?

• Cortical thickening

• Bowing deformity

What tumour like disorder is this, and what can be seen in each image?

Image 1

• Increased density

• Cortical involvement

Image 2

• Bowing

• Psuedo fracture

• Increased density

Image 3

• Bowing

• Ulna showing cortical thickening

What tumour like disorder is this?

Pagets disease

What tumour like disorder is this, what can be seen?

Pagets disease

• Increase in size and density

What tumour like disorder is this?

Pagets disease

What tumour like disorder is this?

What tumour like disorder is this? What fracture can be seen?

Pagets disease

Banana stick fracture

What tumour like disorder is this?

Pagets disease

What tumour like disorder is this?

Pagets sarcoma

What tumour like disorder is this?

Pagets sarcoma

What tumour like disorder is this?

Pagets sarcoma

What tumour like disorder is this?

Pagets sarcoma

What tumour like disorder is this? What are the yellow asterixis showing?

Pagets sarcoma metastasis

Metastases in lung- cannon ball sign

What tumour like disorder is this?

Pagets sarcoma metastasis

What condition was fibrous dysplasia initially confused with?

Hyperparathyroidism

Is Fibrous Dysplasia usually symptomatic or asymptomatic?

Asymptomatic

What is the typical age range for Fibrous Dysplasia?

8-14 years

What is the M:F ratio for Fibrous Dysplasia? What is the exception?

M=F

Except in McCune-Albright syndrome (Mostly Female)

What are the most common causes of symptoms in Fibrous Dysplasia?

• Bowing deformities (shepards crook deformity)

• Pathological fracture

What are the name of the spots seen in Fibrous Dysplasia?

Café au lait spots

Fill the gap. Café au lait spots are present in 30% of patients with ‘x’.

Polyostotic fibrous dysplasia

What does the coast of Maine appearance refer to?

The serrated irregular margins of café au lait spots

What condition are café au lait spots find in other than Fibrous Dysplasia? What is different about the spots?

Neurofibromatosis

Margins are smooth, referred to as coast of California appearance

What are the common sites for monostotic Fibrous Dysplasia?

• Ribs

• Femur (proximal)

• Tibia (anterior cortex)

• skull (75%)

What are the common sites for polyostotic Fibrous Dysplasia?

• femur

• skull

• tibia

• humerus

• ribs

• fibula

• radius

• ulna

• vertebral involvement rare

What does McCune-Albright syndrome represent?

Polyostotic fibrous dysplasia associated with skin pigmentation and precocious sexual development

What does Cherubism mean?

Fibrous dysplasia of the jaw

What are the pathological features of Fibrous Dysplasia?

• Normal bone replaced with abnormal fibrous tissue

• widening of medullary canal

• thinning of cortex

• Endosteal scalloping (lesions of fibrous and cartilagenous matrix)

• Fibrous-based matrix with scattered bony spicules

• (Ground glass appearance) Increased radiopacity to existing radiolucent lesion

• Sarcomatous transformation rare→ femur and skull are targets, fibrosarcoma and osteosarcoma most common complicating tumours

What are the radiological features of Fibrous Dysplasia?

• Skeletal lesions occur several years before puberty

• Radiolucent, loculated or trabeculated in appearance

• Ground glass or smoky appearance or radiolucent lesion (referred to as the wipe out of trabecular patterns)

• (Rind of sclerosis) Lesions demonstrate encapsulated sclerotic border around the geographic lesion

• Bone expansion with widening of medullary canal

• Endosteal thinning

• Scalloping

• Shepards crook deformity of femur common

• Expansile rib lesions often create extrapleural sign

• Pseudo-arthrosis occurs as complication of pathologic fracture and non union→ lower extremity most often affected

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Intertrochanteric lesion- classic location

• Geographic

• Ossification in the centre of the lesion

• Rind of sclerosis

• Narrow zone of transition

• Well defined border

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Subarticular bone is spared (wont see this in pagets)

• Soap bubbly

• Bone expansion

What tumour like disorder is this, what can you see in the first, and the second image?

Fibrous dysplasia

Image 1

• Shepard’s crook deformity

• Coxa vara

Image 2

• Rind of sclerosis

What tumour like disorder is this?

Fibrous dysplasia

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Pathological fracture

• Radiolucent

• Expansile

• Soap-bubbly

• Endosteal scalloping

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Monostotic

• Radiopaque

• Expansile

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Endosteal scalloping

• Radiopaque

• Soap bubbly

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Ground glass/Hazy smokey appearance

• Expansile

• Radiolucent

• Should differentiate from enchondroma

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Polyostotic

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Endosteal scalloping

• Calcification

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Soap bubbly matrix

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Expansile

• Ground glass/hazy smokey appearance

• Radiopaque

What tumour like disorder is this?

Fibrous dysplasia

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Radiolucency

• May see basilar invagination

• If >40, consider Pagets and/or Fibrous dysplasia

• If much younger, consider just Fibrous dysplasia

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Well defined border

• Expansion

What tumour like disorder is this?

Fibrous dysplasia

What tumour like disorder is this, what can you see?

Fibrous dysplasia

• Polyostotic

• Possible picture frame vertebrae

What tumour like disorder is this, what specific feature can you see in the 1st image that explains why bro lookin like buzz lightyear?

Fibrous dysplasia

• Cherubism

What form of Neurofibromatosis are we learning in this course?

Type 1- Von Recklinghausen’s disease

What is Neurofibromatosis?

An inherited disorder that is transmitted as an autosomal dominant

What is the characteristic triad of findings in Neurofibromatosis?

• Café au lait spots

• Fibroma molluscum

• Osseous deformities and lesions

What is the incidence for Neurofibromatosis in number of births?

1/3000

Does familial history play a role in the incidence of Neurofibromatosis?

Yes, 60% familial history

What is the M:F ratio for Neurofibromatosis?

M=F

What percentage of patients with Neurofibromatosis develop café au lait spots

50%

How many café au lait spots are required for the diagnosis of Neurofibromatosis, how long (cm) do they need to be?

6 or more, 1.5cm

What is fibroma molluscum?

An elevated cutaneous nodule that is asymptomatic