12. Occurs only in the tibia and fibula
Infants and children
X-ray: mixed lucent/sclerotic, thickened cortex
(anterolateral), anterior bowing, synchronous
tibia/fibula
DDX: adamantinoma (epithelial nature)
◦ slightly older age >20
18. PF: S.T. mass with vascular calcifications
MRI: T1:
◦ Lacy high signal within lesion represents fat within
lesion
◦ T2 and T1 post Gad: tortuous vascular channels
possible phleboliths
◦ Most common S.T. mass of childhood; intramuscular;
size may vary throughout the day
19.
20. Primary small cell bone neoplasm
Derived from reticulocyte- occurs in areas of red
marrow; long bones, axial skeleton
Diaphyseal- older; Metaphyseal younger
Age: 1st
–2nd
decade; 96% Caucasian
21. Radiography
◦ Highly aggressive tumor; permeative pattern
◦ Medullary tumor; infiltrative; periosteal reaction-
spiculated, lamellated- many layers present
◦ No mineralized matrix
◦ S.T. mass common
◦ DDX: EG, lymphoma, OS, infection
22.
23. Typically metastatic to bone; common tumor in
childhood
In childhood- acute leukemia,
◦ lymphocytic or undifferentiated
50% of children have osseous involvement at
time of DX, and 70-80% during disease
24. Childhood radiographic changes
◦ Radiolucent metaphyseal bands- growth arrest
disturbance; not leukemic infiltrate- involve areas of rapid
growth
◦ Diffuse osteopenia- often the only finding
◦ Periosteal reaction- lamellated
◦ Osteolytic lesions- permeative/ moth eaten
◦ Sclerotic lesions
25.
26.
27. One of the most common bone tumors
Almost always in long bones (femur, tibia)
Age: Usually > 2 y.o. and < 20 y.o.
Histo: fibroblasts and giant cells
Usually regress with age; rarely seen in 30’s
Usually an incidental finding
28. Radiography
◦ Unilateral or bilateral
◦ Osteolytic lesion; well defined; sclerotic margin; oval,
scalloped, lobulated, eccentric,
◦ Metadiaphyseal, cortically based,
◦ Periosteal reaction absent- unless path fracture
◦ Femur: posteromedial; healing begins in diaphyseal
region
41. Long bones- (prox humerus/ femur) metaphyseal-
move toward diaphysis with bone growth
Age: 1st
two decades of life
Bone cyst- serosanguineous fluid
Bony septations
Pathologic fractures 2/3’s of cases
42. Radiography
◦ Well-defined lytic lesion- central in medullary space;
bone expansion, sharp margin
◦ Periosteal reaction only in presence of path fracture-
“fallen fragment sign”
◦ Radiolucent with trabeculation
◦ DDX: FD, ABC, NOF
43.
44.
45.
46. Nonneoplastic lesion of bone
(reticulohistiocytosis)
Usually solitary- EG
◦ Multiple- Hand-Schuller-Christian
◦ Systemic- Letterer-Siwe
◦ Long bones, skull, spine, ribs, pelvis
◦ Age: 1st
two decades (5 – 10 y.o.)
50. Metaphyseal- epiphyseal lesion; long bones
Age: 20 - 50 y.o. (growth plate closed) rare under
age 15 y.o.
Progressive potentially malignant lesion
Histo: Giant cells and mononuclear spindle
shaped cells
51. Radiography
◦ Lytic lesion; arises in metaphysis and extends into
epiphysis; growth plate closed
◦ Well defined, nonsclerotic margin, abuts articular
surface, eccentric, usually large (> 4-6cm)
◦ Radiographic appearance does not help in determining if
benign or malignant
52.
53.
54. Exostosis; bony projection with a cap of hyaline
cartilage; aberrant cartilage
Metaphyseal, points away from joint; long bones,
around knee
Age: 2nd
decade; growth stops when growth plate
closes
Single or multiple; sessile, pedunculated
Malignant potential; increase with multiple lesions
55. Radiography
◦ Bony projection; contiguous medullary space and cortex;
overlying cartilage cap
◦ Pedunculated/ sessile
◦ Pain- malignant transformation/ mechanical problems,
bursa formation
◦ Cartilage cap; normally < 1-2 cm
56. DDX:
◦ Single lesion: Parosteal osteosarcoma (no continuity of
medullary space and cortex)
◦ Multiple: Enchondromatosis; FD
◦ Malignant Transformation: Chondrosarcoma;
Pain; Growth after growth plate closes
Cartilaginous cap > 2cm thick
60. Similar to osteoblastoma; < 2 cm in size
Femur/ tibia/ bones of the hands/ feet/ spine
Usually cortical;Fibrovascular nidus (< 1cm);
adjacent reactive bony sclerosis
Night pain relieved by aspirin
Age: < 25 y.o.
61. Radiography
◦ Round/ oval radiolucency (nidus <1-2cm)
◦ Cortically located
◦ Thick adjacent bony sclerosis
Nucs: “Target” sign; MR: Nidus- bright on T2
with marked enhancement with Gad; CT used
to identify the nidus
DDX: stress fracture, osteomyelitis
62.
63. Malignant bone tumor that forms osteoid tissue
Most common primary malignant bone tumor
other than multiple myeloma
Involves areas of active growth; Metaphysis;
femur, humerus, tibia, pelvis
Age: 2nd
decade
69. Radiography
◦ Effusion present; abnormal calcifications
◦ Ossified loose bodies seen on plain film
◦ Cartilaginous loose bodies seen on MR
◦ Secondary OA
◦ Pressure erosive changes
