Hard Tissue Final Flashcards
(111 cards)
1
Q
Metastatic Bone Tumors
Primary Malignant Bone Tumors
General information
A
m/c malignant tumors of skeleton
• 70% are metastatic in origin
• 30% are primary tumors
• most are mets from a primary extra-skeletal focus- majority are epithelial in origin.
2
Q
Metastatic Bone Tumors
Primary Malignant Bone Tumors
Most common primary sites of origin
A
breast • lung * 80% of bone mets • prostate are from these sites • kidney • thyroid • bowel
3
Q
Metastatic Bone Tumors
Primary Malignant Bone Tumors
Female Metastasis stats
A
- breast cancer —————-70% bony metastasis
* thyroid, kidney uterus —–30% bony metastasis
4
Q
Metastatic Bone Tumors
Primary Malignant Bone Tumors
male Metastasis stats
A
• prostate cancer ————-60% bony metastasis
• lung ————————–20 % bony metastasis
- other ————————-20%
5
Q
Metastatic bone tumors
Clinical features
A
• usually 40 or older • recent weight loss • anemic • fever in advanced stages MAJOR--->• principle sign: • persistent nocturnal pain • pathologic fracture
6
Q
Metastatic bone tumors
Clinical features cont.
A
• increased serum calcium in osteolytic mets;
however in most cases this is WNL.
- increased alkaline phosphatase and PSA with cancer of the prostate when capsule has been broken and Batson venous plexus has been seeded.
- occurs by direct invasion or seeding.
- not unusual to detect an metastatic lesion 10 to 15 yrs after treatment for a primary lesion
7
Q
Pathologic Features of Primary Malignant Bone Tumors
Pathways of metastasis
4
A
• Direct extension— soft tissue tumor lying adjacent to bone
eg; ca of uterus ==> iliac bone
• Lymphatic extension
uncommon because of lack of lymphatic channels- bone
• Hematogenous dissemination
• veins m/c pathway
• thick walls of arteries usually resist
- tumor penetration
- Batson’s venous plexus
- provides passageway for cancer cells to invade bone
8
Q
Lytic vs. Blastic
Lytic lesions
A
- tumor emboli into bone marrow
- present a long time
- 50-70% of bone density lost before seen on radiograph
- lytic lesions occurs as a result of pressure erosion from medullary tumor deposits and are unrelated to osteoclastic activity.
*The “L’s”
Lytic, lucent, ladies, loss of bone density
9
Q
Radiologic features - bone scans 6
A
- detect 3% to 5% alteration of bone metabolism (mets).
- Tc-99m phosphate or diphosphonate (Tc-99mn-DP) .
- areas of metastasis appear hot = increased uptake.
- up to 40% of pt’s with abnl bone scans have nl x-rays.
- bone scans may detect mets ~ 18 months before they- are seen on x-rays.
- sensitivity 50 to 80% greater than conventional x-rays.
10
Q
Xray vs Bone Scan differences in bone density sensitivity
A
A bone scan can detect alterations of as little as 3% to 5%, while on
x-ray ~ 30 – 50% loss of bone density is needed before it can be detected
on x-ray. Detection = “hot” areas.
11
Q
Most involved part of spine for metastasis
A
most frequently involved components of the spine are the vertebral bodies and pedicles
12
Q
metastasis stats
A
- 28% in the ribs and sternum.
- 39% in the vertebrae.
- 13% in the pelvis.
- 10% in the skull.
- ~ 10% in the long bones.
- mets distal to the knees and elbows are rare.
13
Q
CT: Computed Tomography
gen info
A
- more sensitive than x-rays/plain film studies.
- useful in detecting cortical bone involvement.
- useful in detecting associated soft-tissue masses.
14
Q
MRI: Magnetic Resonance Imaging
gen info
A
- superior to CT in detection of both bone lesions and adjacentsoft tissue masses.
- infiltration of tumor cells into the fatty marrow is seen as ypointense on T1 weighted images, these areas show yperintense on T2 weighted images.
15
Q
Fundamental Roentgen Signs 4
A
• alteration of bone density and architecture
- 75% are osteolytic which is seen as:
- moth-eaten
- permative
- 15% are osteoblastic seen as :
- snowball pattern
- 10% of metastatic lesions are seen as :
- bubbly, highly expansile assoc.. w/ renal or thyroid malignancies
16
Q
Fundamental Roentgen Signs 3
A
• vertebral body and pedicles common sites of metastasis
- ivory vertebra seen in:
- Pagets—increased size / enlarged
- Hodgkins Lymphoma — anterior scalloping of vertebral body
• periosteal response is RARE
17
Q
Primary vs Secondary Tumors
A
Primary Secondary 30% 70% expands bone periosteal response solitary lesion multiple lesions soft tissue. Mass
18
Q
Benign tumors
A
radiolucent lesion
well-defined margins
rim of sclerosis
cortex intact or thickened
may cause bone expansion without cortical destruction
bone adjacent to lesion is normal
short zone of transition
no soft tissue mass
no periosteal reaction or pain
19
Q
Malignant Tumors
A
bone destruction- (loss of density)
irregular, ragged, ill-defined- margin
poorly circumscribed areas- of increased density
cortical erosion or destruction
long zone of transition
may have soft tissue mass adjacent- to bone destruction
periosteal reaction
- spiculation - sunburst - laminating - Codman’s triangle
pain irregular cloud of density
20
Q
Metastatic Bone Tumors
Osteoblastic metastatic carcinoma
clinical features
A
> 40 yr old males
• persistent nocturnal pain
• weight loss
21
Q
Osteoblastic metastatic carcinoma
Radiologic features
A
- increased bone density - radiopacity
- snowball/cotton ball appearance
- vertebral bodies & pedicles common site
- ivory vertebrae
22
Q
Osteoblastic metastatic carcinoma
Lab
A
- increased acid phosphatase with prostatic cancer
* possible increased alkaline phosphatase
23
Q
Osteoblastic metastatic carcinoma
Misc. information
A
- 15% of metastatic lesions
* usually occurs 10-15 years after surgery or tx of primary - neoplasm (e.g. prostate cancer)
24
Q
Osteolytic metastatic carcinoma
Clinical features
A
• 40 + y.o. females
• pain at night
• wt loss
.
25
Osteolytic metastatic carcinoma
| Radiological features 5
* moth-eaten / permeative pattern
* long zone of transition
* vertebral bodies and pedicles commonly effected
* one-eyed pedicles / winking owl sign
* blind vertebra = bilateral lysis of pedicles
26
Osteolytic metastatic carcinoma
| • Misc. info
• 75% of all metastatic carcinoma
```
• usually occurs 10-15 years after surgery or tx of
primary neoplasm (eg. Breast cancer).
```
• increased serum calcium.
27
Primary Malignant Bone Tumors
| 4
* 1 - Multiple myeloma
* 2 - Osteosarcoma
* 3 - Chondrosarcoma
* 4 - Ewing’s sarcoma
28
Multiple Myeloma
| general info
* a.k.a. Kahler’s disease
* • ~ 75% of pt’s are between 50 and 70 yrs of age; mean age 60.
* rarely seen before the age of 40; few cases have been reported below 30.
* male:female 2:1
* m/c primary malignant bone tumor
29
Multiple Myeloma
| clinical features
* 50-70 yr old males.
* pain relieved with bed rest.
* pain aggravated by weight bearing.
* attacks:
* spine m/c
* pelvis
* ribs
* scapula
30
Multiple Myeloma
| labs
* reversed A/G ratio (albumin/globulin)
* 40% show Bence Jones proteinuria
* hypercalcemia is present in ~ 30% (2nd to lytic destruction aused by the myelomatous tissue.)
31
Multiple Myeloma
| radiologic features
* gross osteoporosis (only early sign)
* punched-out lesions = Hallmark of disease
* vertebra plana (uniform collapse)
* raindrop skull (lytic lesions)
* pedicle sign (pedicles visible or preserved on a collapsed vertebra)
32
Multiple Myeloma
Summary
Solitary plasmacytoma
* represents a localized form of plasma cell proliferation.
* m/c bones affected are mandible, ilium, vertebrae, ribs,- proximal femur and scapula.
* typical lesion has a geographic, soap bubbled, highly
33
Multiple Myeloma
Summary
Treatment & Prognosis
* 90% die within 3 years.
| * tx is radiotherapy with chemotherapy.
34
Solitary Plasmacytoma 5
| gen info
* represents a localized form of plasma cell proliferation.
* is less common than multiple myeloma.
* ~ 50% of pt’s present before the age of 50.
* plasmacytoma is a localized form of multiple myeloma.
* is less aggressive than the diffuse form of multiple myeloma.
35
Osteosarcoma - a.k.a.
osteogenic sarcoma
36
Osteosarcoma
| gen info 3
• 1º malignant tumor of bone (undifferentiated connective tissue).
• derived from undifferentiated connective tissue
- forms neoplastic osteoid.
• 2nd most common primary malignant tumor.
37
Osteosarcoma
| • 5 clinical types
* central osteosarcoma
* multicentric osteosarcoma
• parosteal osteosarcoma
- (juxtacortical osteosarcoma).
* secondary osteosarcoma
* extraosseous osteosarcoma
38
Osteosarcoma
| Clinical features
* ~75% 10 to 25 yr. old males
* painful swelling of the involved limb
* most common sites:
* distal femur
* proximal tibia
* proximal humerus
39
Osteosarcoma
| lab
* increased alkaline phosphatase
| * levels are highest with the sclerotic type
40
Osteosarcoma
| radiological features 6
* ivory or sclerotic medullary lesion in the metaphysis of a -long bone
* “sunburst” / “sunray” periosteal response
* codman’s Reactive Triangle – often
* cortical disruption w/ soft. tissue mass formation
* cumulus cloud formation is the peripheral edge of an eccentric lobulated mass that has roughened and had irregular margins
* TX: amputation (treatment of choice ????)
41
Chondrosarcoma
| gen info
* malignant tumor of chondrogenic origin that remains cartilaginous throughout its evolution.
* third most common primary malignant bone tumor.
42
Chondrosarcoma
Clinical features
3
* 40-60 year old males.
* pain after development of soft tissue mass - (occurs late in the disease process)
* m/c sites:
* pelvis
* proximal femur
* humerus
* ribs
* scapula
* sternum
* craniofacial bones
* proximal tibia
43
Chondrosarcoma
| Radiologic features 6
* round, oval radiolucencies with ill-defined margins.
* metaphysis or diaphysis.
* popcorn matrix calcification in lesion 2/3’s of time.
* radiolucent lesion 1/3 of time.
* laminated or spiculated periosteal response.
* contours of bone enlarged or expanded.
44
Chondrosarcoma
| Misc. information
• m\c primary malignant bone tumor of scapula.
• of chondrogenic origin and remains essentially
cartilagenous through-out its evolution.
45
Ewing’s sarcoma
| gen info 5
* 4th m\c primary malignant bone tumor.
* represents ~ 7% of all primary malignant bone tumors.
* decreased incident among African Americans.
* is comprised of tumor cells derived from the connective tissue framework of bone marrow.
* highly malignant tumor.
46
Ewing’s sarcoma
| clinical features
* 10-25 year old males.
* pain with swelling at lesion site.
* only primary malignant bone tumor with symptoms that simulate infection.
47
Ewing’s sarcoma
| Most common sites
* most common sites
* long bones of the lower extremity.
* femur
* tibia
* fibula
* innominate =most common flat bone.
48
Ewing’s sarcoma
| signs and symptoms
• localized pain and swelling at the site of the lesion.
• pain is dull at first and then it becomes severe
- and persistent a few months prior to dx.
• a soft tissue mass is often palpable.
* systemic sx’s
* slight to moderate fever.
* increased ESR.
* 2nd anemia.
• Ewing’s appears to be the only primary malignant bone tumor with sx’s simulating infection.
49
Ewing’s sarcoma
| radiological features
* permeative lesion in diaphysis with onion skin periosteal response.
* cortical “saucerization” = characteristic sign.
* Codman’s triangle is frequently present (not as often as in osteosarcoma.)
50
Quasi-malignant bone tumors
| Giant Cell Tumor
* a.k.a. osteoclastoma
* is a quasi-malignant bone tumor.
* quasi-malignant
* ~ 80% are benign
* ~ 20% are malignant
51
Giant Cell Tumor
| Clinical features
* 20 to 40 year olds.
* males -> malignant tumors.
* females -> benign tumors.
* aching pain with restricted motion
52
Giant Cell Tumor
| m/c sites (in decreasing order)
* distal femur
* proximal tibia
* distal radius
• carries a more serious prognosis since most
of these lesions are malignant.
* proximal humerus
* sacrum is the m/c site in the spine (~ 8% of cases).• it a benign tumor of the sacrum.
53
Giant Cell Tumor
• usually begins in the metaphyseal end of a long bone
• usually extends to the end of a long bone where it
abutts the joint surface leaving the lesion ubarticular.
54
Giant Cell Tumor
| signs/symptoms
* is intermittent pain which is aching in nature.
* localized swelling and tenderness.
* frequently there is restricted motion present at the involved joint.
55
Giant Cell Tumor
| Radiologic features
• metaphysis and extends to subarticular location after- epiphyseal plate has closed.
* radiolucent, eccentric metaphyseal lesion.
* soap bubble expansion.
56
Primary Benign Bone Tumors
Osteochondroma
gen info
* m/c benign skeletal tumor ~50% of all benign tumors.
* bony exostosis projecting from the external surface of a bone.
* usually has hyaline-lined cartilaginous cap.
57
Osteochondroma
| clinical features
* most osteochondromas are seen in pt’s in their childhood or adolescent years.
* ~ 75% are seen in pt’s < 20 yrs of age (males).
* the lesions are often not detected until later in life when the pt is x-rayed for another reason.
* 2:1 male preponderance.
58
Osteochondroma
| Radiologic features
* the knee, tibia and femur are the m/c sites.
* metaphysis m/c site of origin.
* pedunculated type has an osteocartilaginous cap domed cap on a long slender stalk.
59
Osteochondroma
2 types
type 1
• sessile-------->>>>
* broad flt base without a stalk.
* humerus and scapula.
60
Osteochondroma
2 types
type 2
* pedunculated
* has a long stalk attaching it to the bone.
* knee, hip, and ankle.
* “coat-hanger exostosis” = pedunculated. Growing away- from the joint on the metaphysis.
* lesions appear as a cauliflower mass.
* cap of exostosis is cartiginous (hyaline) and is often - lobulated.
61
HME or Hereditary Multiple Exostosis
* unknown etiology.
* inherited metaphyseal overgrowth with multiple osteochondromas
- discovered b/w 2-20
- females = males
- most commomly affects metaphysis of: knee, ankle, shoulder, wrist (usually bilateral)
62
Hemangioma
clinical features
4
* most lesions are seen in pt’s over 40 yrs of age (females > males).
* most lesions develop after puberty and then remain undetected until later in life when they may be detected incidentally.
* incidence is higher in females.
* most lesions are asx at any body site.
63
Hemangioma
clinical features
3more
• most symptomatic spinal lesions are the result of expansion leading to the development of spinal stenosis.
pt’s may present with impending paraplegia.
• 70% to 75% of lesions occur in the spine, the lower thoracic and upper lumbar spine and the frontal bone are affected the most.
64
Hemangioma
| radiological features 5
* classic spinal lesion is on with coarse vertical striations within the vertebral body which has been called corduroy cloth appearance or striated vertebra.
* prison bar
* usually solitary
* NO cortical endplate thickening
• skull lesions are round or oval radiolucency radiating
- “sunburst” or “spoked wheel”.
65
Hemangioma
radiological features
2 more
• vertebral expansion may rarely occur in hemangiomas creating
- an appearance similar to that of Paget’s disease of the- spine. Differentiation is made by the lack of cortical- endplate thickening in hemangioma - a finding which- is present in Paget’s disease.
• most skull lesions are found in the frontal bone, creating a
- round or oval radiolucency, a radiating sunburst or
- spoked wheel appearance that extends from the
- center of the lytic defect.
66
Hemangioma
| tx and prognosis
• most lesions are clinically silent and do not require tx.
• sx spinal lesions are either fx’ed or are expanding bone
- creating spinal stenosis.
* surgical decompression may be needed under these circumstances.
* XRT may be used occasionally in inoperable vertebral hemangiomas.
* skull lesions are easily tx’ed by en bloc excision and have a favorable- prognosis.
67
Osteoma
| gen info
• benign bone tumors arising in membranous bones.
• most are asx; therefore true incidence is unknown.
• most lesions are clinically silent.
• most lesions occur in the frontal and ethmoid sinuses.
• most are not id’ed until adulthood.
• they may interfere with the drainage of a sinus or may lead to chronic
- retro-orbital pressure, h/a’s,
• most never reach a size > 2 cm.
• they can become very large, nearly filling a sinus (giant osteoma).
68
Bone Island aka
enostoma
69
Bone Island
| gen info
* a discrete area of solitary sclerosis within the skeleton.
* usually asymptomatic.
* bone islands can be 1-4 cm in size.
* are common in the ischium, ilium, sacrum, proximal femur, - humerus, vertebra, talus, scaphoid and ribs.
* do not occur in the skull.
* are homogeneously dense and well marginated.
70
Bone Island
| clinical features
* clinical features
* may be found at any age, are more common in adults than in children.
* usually appear unchanged in size over many years. may grow on occasion.
* etiology is unknown.
* pathologic features
* bone island represents a focus of compact lamellar bone located within normal spongiosa.
* histologic appearance is the same as that seen with- osteopoikilosis.
* the former is usually solitary and the latter consists of- multiple areas of sclerosis.
71
Bone Island
| pathological features
• is a focus of compact lamellar bone which is located within
- normal spongiosa.
72
Bone Island
| radiological features
* usually intramedullary ovoid, round, or oblong radiopaque densities
* has sharp margins.
* may have thorn-like radiating spicules of bone referred to
73
Osteoid Osteoma
| Clinical features
* 2:1 male:female
* 10-25 year old age group.
* severe pain that is worse at night is characteristic. pain dramatically relievedby aspirin.
* muscle atrophy and limp in long standing lesions.
* ~ 50% are found in the femur and tibia.
* ~ 10% occur in the spine, neural arch.
74
Osteoid Osteoma
| pathologic features
• tumor has a nidus, usually 1 cm or less in size.
75
Osteoid Osteoma
| radiologic features
• characteristic appearance of a cortical lesion is a radiolucent- nidus surrounded by florid reactive sclerosis.
76
Osteoid Osteoma
| differential dx
* Brodie’s abscess mimic's osteoid osteoma.
* differentiation cannot be made clinically as both present with similar hx’s.
* central nidus which is usually > 1cm in Brodie’s abscess suggests a difference.
77
Solitary Enchondroma
| gen info
* solitary enchondroma is a common benign bone tumor arising in- residual islands of cartilage left in the metaphysis as the - physis grows away.
* appears as a single lesion within the interior of the bone.
* has a predilection for the bones of the hand and feet.
* often found incidentally.
* most lesions are asx.
* incidence
* m/c benign bone tumor of the hand.
* ~10% of all bone tumors.
78
Solitary Enchondroma
| clinical features
* tumor arises during the growth period.
* most are seen between the ages of 10-30 yrs old.
* males = females.
79
Solitary Enchondroma
| radiologic features
* hands and feet
* hand - expansile lytic lesion of the phalanx.
* usually within the metaphysis & centrally placed.
* central matrix calcification
* geographic lesion
* central
* thinned cortex
* expansion
* 50% stippled calcification
* pathologic fx
80
Multiple Enchondromatosis aka
(Ollier’s disease)
81
Multiple Enchondromatosis
| general features
* presence of central chondromas or enchondromas in multiple sites is - referred to an multiple enchondromatosis.
* originally described a French physician Ollier.
* enchondromatosis is a cartilage dysplasia of bone representing an inborn anomaly of enchondral bone formation.
* this anomalous bone formation leaves unossified cartilagenous remnants in the diaphyses and metaphyses.
82
Multiple Enchondromatosis
| clinical features
* pain is rarely associated with the multiple enchondromas unless there is associated trauma or fracture.
* large lesions are associated with deformity and loss of limb function.
* most frequently involve small bones of the hands and feet.
* femur and tibia are frequently involved.
* iliac crest is the most frequently involved flat bone.
83
Multiple Enchondromatosis
| radiologic features
* lesions are similar to solitary enchondromas.
* round or oval radiolucency that creates a symmetric widening of the bone.
* central matrix calcification is common.
* lesions can be eccentrically located causing bony expansion.
* metaphyseal lesions often have streak-like or vertical bands of- radiolucencies projecting towards the diaphysis of the bone.
84
Fibrous Xanthoma of Bone - Nonossifying Fibroma (NOF)
| description
* Fibrous xanthoma is a term that includes several lesions under one - two major names: nonossifying fibroma (NOF) and fibrous - cortical defect (FCD).
* most believe these two lesions to be identical lesions occurring in- pt’s of different age groups.
* only differentiating factor is the pt’s age.
* FCD occurs in the 4 to 8 yr old group.
* NOF occurs in the 8 to 20 yr old group.
85
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| general
* NOF has a lot of synonyms:
* nonosteogenic fibroma
* metaphyseal fibrous defect
* solitary xanthoma
* xanthogranuloma of bone
* fibrous medullary defect
* thought to represent faulty ossification, rather than a true neoplasm.
86
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| incidence
* majority of lesions are asx/silent therefore the true incidence is uncertain.
* about 30% to 40% of normal children have FCD.
* NOF is less common than FCD.
87
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| • clinical features
* affects pt’s from 8 to 20 years.
* average age affected is 14.
* male:female is 2:1.
88
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| signs/symptoms
* most lesions are asx.
* most are found on x-rays taken for other reasons.
* lesions > 8 cm cause persistent pain and may weaken the bone.
* pathologic fx’s can occur; especially in teens/young adults.
89
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| location
* m/c affects bones of the lower extremity.
* distal tibia most frequent site.
* other sites:
* proximal tibia
* distal femur
* fibula
* proximal humerus
90
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| pathological
• NOF and FCD are identical histologically
91
Fibrous Xanthoma of Bone - Nonossifying Fibroma
| radiologic features
* typical lesion in NOF is a solitary, radiolucent, eccentric, and - is generally ovoid shaped.
* often thins and expands the cortex.
* has scalloped margins.
* often has a multilocular, bubbly appearance.
* osteolytic area varies from 2 to 7 cm.
92
Simple Bone Cyst
| general
* simple bone cysts are sometimes called unicameral bone cysts,solitary bone cyst, or juvenile bone cyst.
* is not a true neoplasm
* is a fluid filled cyst that is lined with a thin layer of fibrous tissue.
93
Simple Bone Cyst
| clinical features
* m/c occurs in pt’s between the ages of 3 and 14 years (80%).
* male:female = 2:1.
* most lesions are asx until a pathologic fx occurs.
* about 2/3’s will develop pathologic fx’s.
* m/c in the proximal humerus and femur (75% ).
94
Simple Bone Cyst
| pathologic features
• a simple bone cyst is a fluid-filled cavity present within the metaphyseal portion of the growing long bone.
95
Simple Bone Cyst
| radiologic features
* classic appearance is a geographic or cystic radiolucency which is broad at the metaphyseal end and narrower at the diaphyseal end.
* lesion is radiolucent, except for a thin septa, which creates a bubbly or loculated appearance.
* the loculation is pseudo or incomplete, because no complete septation- is present.
96
Aneurysmal Bone Cyst - ABC
| general features
• nonneoplastic solitary lesion of bone consisting of a cystic cavity
filled with blood.
• it is not an aneurysm and it is not a true cyst.
• it is composed of channels containing flowing blood.
• it has a sponge like appearance.
• true pathogenesis is unknown.
97
Aneurysmal Bone Cyst - ABC
| clinical features
* ~75% of cases are seen in pt’s between the ages of 5 and 20 yrs old.
* ~60% of cases are seen in females.
98
Aneurysmal Bone Cyst - ABC
| signs/symptoms
• c/c is the cute onset of pain at the affected site with a rapid increase in severity over a short time.
.....pathologic fx’s are common
• more so with expanding and destructive lesions.
• spinal lesions may produce neurological sx’s; even paraplegia.
• lesion prefers the neural which results in spinal stenosis.
• a hx of trauma is often obtained in these pt’s.
99
Aneurysmal Bone Cyst - ABC
| location
* ~80% of lesions are located in long tubular bones and the spine.
* ~20% of lesions affect the flat bones and short tubular bones.
* femur and tibia m/c long bones affected.
100
Tumor like Processes
| Misc Conditions 2
1) Pagets
| 2) Fibrous dysplasia
101
Paget’s disease
| general
* Sir James Paget described the disorder in 1877.
* a.k.a Osteitis deformans
* Paget’s disease is a great imitator of bone diseases, along with fibrous dysplasia.
102
Paget’s disease
| clinical features
* 2:1 male:female.
* rare before age 40; m/c after age 55.
* 90% of pt’s are asx.
* pain, if present is of low intensity. Pain may associated with bowing deformities or fx.
* m/c bones affected are pelvis, vertebrae, clavicle, humerus, ribs, with - the fibula being affected the least in uncomplicated form of Paget’s.
* increasing hat size is common.
* subarticular location is common. Usually extends into the diaphysis.
103
Paget’s disease
| complications
• deformity of the involved bones. These include: shepherd’s crook deformity of the proximal femur (coxa vara), saber shin deformity (anterior tibial bowing), protrusio acetabuli, leontiasis ossea, frontal and parietal bossing, and basilar invagination.
* pathologic fx of the vertebral body and transverse banana like fx of long bones is common.
* pseudofractures are seen as areas of demineralization within the bone, which is replaced by fibrous tissue.
* spinal stenosis may occur as a result of bony expansion of a vertebra, leads to compressive neuropathy.
104
Paget’s disease
| lab findings
• because of osteoclastic activity there is enhanced bone collagen
destruction which causes an increase in urinary hydroxyproline.
• alkaline phosphatase increases; sometimes 20x normal.
• hypercalcemia can occur.
105
Paget’s disease
| pathologic features
* replacement of normal bone by pagetic, vascular, and fibrotic bone has been called mosaic structure of Paget’s disease.
* four stages of pagets:
* Stage one: osteolytic, destructive, monophasic.
* Stage two: combined, mixed, biphasic.
* Stage three: sclerotic or ivory.
* Stage four: malignant degeneration.
106
Stage one Pagets
osteolytic, destructive, monophasic
107
Stage two Pagets
combined, mixed, biphasic
108
Stage three Pagets
sclerotic or ivory
109
Stage four Pagets
malignant degeneration
110
Paget's Disease
| radiologic features
* bone scan lesions will be hot.
* skull lesions demonstrate the lytic stage of osteoporosis circumscripta,more advanced lesions of the combined stage show a cottonwool appearance.
* spine: vertebra a thickened and enlarged endplate, creating a squared-off, picture frame vertebra. This occurs during the biphasic stage.
* homogeneous increase in radiopacity of the vertebral body creates the ivory vertebra appearance.
* m/c causes for Ivory Vertebra include: osteoblastic carcinoma, Paget’s disease, and Hodgkin’s lymphoma.
111
Paget’s disease
| radiologic features contsd
* pelvis: cortical thickening and bone expansion seen in the pelvis as thickening of the iliopectineal line, obliterating Kohler’s teardrop, this has been called the brim or rim sign.
* long bones: tibia is the 2nd m/c site of lytic Paget’s disease, with the - skull being the m/c. Begins in the subarticular end of the - proximal tibia with extension down the shaft in a characteristic - candle flame or V-shaped appearance, this is often called - a blade of grass appearance.
