1. Bone Pathology 1
Practical 1

2. OSTEOMA M/c in men Age: 50-60yrs M/c asymp., Sx’s dep. in location
M/c in: Sinuses, inner/outer tables of skull, some facial bones
Solitary, radiodense, homog. opacity w/smooth & lobular margins
Related to Gardner’s Syndrome

4. Enostosis= “Bone Island” =Enostoma
At all ages,m/c in adults
M/c asymp.
In all skeleton, except skull. pelvis,humerus, vertebra,ribs
Don’t cross articulation
Well demarcated,round-oval, homog. radiopaque w/speculated margin(brush border).Normal adjacent cortex.
Epiphyseal/metaphys.; medullary

8. Osteopoikilosis Multiple bone islands
Autosomal dominant; sclerosing dysplasia
m/c in males
Rare before 3yrs of age
M/c asymp., mild joint pain
Small radiopacities(multiple)
Metaephyseal reg. of long bones
Adjacent to acetabulum of pelvis + scapular glenoid;also carpals and tarsals

11. Osteoid Osteoma M/c in male Age: 10-25yrs
Sx.’s: Pain > night relieve by aspirin,localized swelling, dec. ROM, painful limp, weakness w/muscle atrophy
50-60%: femur(*prox.) + tibia
20%:hands & feets
10%Vertebral lesions(*lumbar)-m/c from *neural arch(TVP base,lamina,pedicle)In concave side.

12. Osteoid Osteoma,cont... M/c @ cortex
Centrally located, oval to round radiolucent foci(nidus)-*< than 1cm surrounded by uniform bone sclerosis
Metaphyseal/dyaphys. in long bones
Differentials: Garre’s Sclerosing Osteomyelitis, Brodie’s Abscess,*Stress Fracture 12

14. Nidus

16. Osteoblastoma M/c in males Age: 10-30yrs.
Sx.’s: Local pain; in spine lesions: muscle spasm,scoliosis & neurolog. Sx.’s
Spine(*target-lumbars)-1arily post.elements(pedicles + lamina)
Tubular bones m/c lower extremities
Diaphyseal/metaphys. of long bones
Cortical or medullary, may be subperiostal

17. Osteoblastoma, cont...
Well circumscribed, expansile lesion, *radiolucent or mottled mixed lytic-blastic w/cortical thinning(eggshell like). *Nidus >2cm. Osteosclerosis may be, but soft tissue is infrequent.
Different. Dx.’s: osteoid osteoma,simple or aneurysmal bone cyst, eosinophilic granuloma,enchondroma and fibrous dysplacia 17

20. Osteosarcoma “2nd m/c 1ary malignancy of bone” M/c in male
M/c in 2nd & 3rd decades(10-25yrs)
Sx.’s: Pain,swelling,dec. ROM, warmth, pyrexia.Lab. Anal.:high lev. alkaline phosphatase
long tubular bones: *femur(40%),tibia(16%),humerus(15%) Around knees % cases
*Metaphyseal, extension to diaph/epiphys.

21. Osteosarcoma,cont...
Mixed pattern of osteolysis & sclerosis w/extensive bone prod.-seen as cumulus cloud appearance. Permeative pattern of destruction, wide zone of transition w/cortical disruption,*soft tissue extension + *aggresive periostal Rx’n.(*sunburst).Pathological fracture may be present.
m/c intramedullary; metaphyseal
Differ.Dx’s: Ewing’s sarcoma & metastasis 21

25. Osteochondroma “M/c benign skeletal tumor”-50%of all
HME(heredit.mult.exostoses)w/fam.history
Bony excrescences covered by cartil. cap
M/c in males
70-80% before 20yrs
M/c asymp., w/painless,non-tender slow growing mass
Femur(30%),humerus(20%),tibia(17%),pel vis,scapula,ribs,spine
Metaphyseal, other regions are rare

26. Osteochondroma,cont...
Metaphys/diametaphys. osteocartilaginous excrescence:pedunculated or sessile.
Oriented *Away from articulat.Calcification may be seen(cauliflower,spotty).Cart.cap in adults:<or=1cm(if >2cm- danger!);children:3cm,normal
Other possible Sx.’s:fracture,osseous deformity,vasc.injury,bursa,neurol. compromise,malignant transformation
Differ. Dx’s: Osteochondromas-generally diagnostic. 26

30. Multiple Hereditary Exostosis

31. Enchondroma “M/c benign tumor of the hand” No gender predilection
Age: 10-30yrs
Sx.’s: m/c asymp., painless swelling
hand(*prox.phalanges & metacarpals are m/c).25% in Long bones,>frequent in lower extremities
Well defined,expansile,medullary w/*calcification(50%cases) and endosteal erosion(scalloping)that lead to cortical thinning

36. Chondroblastoma Codman’s Tumor
“2nd m/c benign tumor of patella”
M/c in males
Age: 10-25yrs
Sx.’s: mild,dull pain,often refer to adjacent joint,local tenderness & occasionally swelling.Musc. atrophy w/weakness may present.
M/c in distal/prox femur(*trochanter), prox/tibia, prox.humerus(*tuberosity) & ilia.
Medullary based; epiphys. often w/metaphyseal extension

37. Chondroblastoma Codman’s Tumor
Round-oval shaped well-defined lytic lesion. Fluffy cotton wool matrix calcif. Sclerotic rim.
Stippled or punctuate calcific.(50%cases) & periostitis in metaphys.(30-50%cases)
Differ. Dx.’s: Giant Cell Tumor(GCT), Brodie’s Abscesses, Eosinophilic granuloma 37

41. Chondromyxoid Fibroma
No gender predilection
Age:Under 30 and 6th-7th decades
Sx’s:Progressive local.pain,may be swelling
50%-prox.metaphysis of tibia(*tuberosity) Also at femur,humerus,fibula,ribs,pelvis & tubular bones
Large eccentric, well defined,ovoid lytic lesion, narrow transition zone, endosteal scalloping & trabeculation(soap-bubbly).Extensive(“bite defect”).Calcif. is RARE.
Differ.Dx:ABC,GCT,enchondroma,chondro&os teo-blastomas,fibrous dysplacia,NOF

44. Chondrosarcoma “3rd m/c 1ary malignancy of bone”
“M/c 1ary malignant tumor of tubular bone of hand & chest wall”
M/c in men
Age: 40-60yrs
Sx’s: Pain w/assoc. swelling 2ary to soft tissue mass
In any bone forming from cartil.; pelvis + prox. femur-50%cases; also in humerus, scapula,ribs, bones around knee

45. Chondrosarcoma
Aggressive,large,expansile,radiolucent,ill- defined borders, wide zone of transition w/endosteal scalloping or complete cortical dissolution, erratic calcif.(may be stippled, fluffy-cotton wool or arcs & rings in appearance) *Soft tissue mass(can become very large)w/scattered calcif. Periosteal rx’n(laminated or speculated appearance.
Matrix calcif.-65%cases
Metaphyseal, but can occur purely epiphyseal
Differ.Dx:Enchondroma,chondromyx.fibroma + metastatic disease 45

51. Fibrous Cortical Defect Non-Ossifying Fibroma
M/c in males
Age: FCD:4-8yrs; NOF:8-20yrs
Lower extremities; 55% near knee
FCD:small,eccentric,metaphys.,rim of sclerosis parallel to long axis.*Post.distal femur m/c site
NOF:solitary,well-def.,often multilocular-bubbly, oval shaped,radiolucent,2-7cm,eccentrical @metaphysis of long bone(*distal tibia) w/cortical expansion +thinning

55. Fibrosarcoma No gender predilection Age: 30-50yrs
Sx’s: Local pain,limited ROM. 1/3 assoc. w/pathol. fracture
70%Long tubular bones(femur-40%& tibia16%)
Metaphys. or diametaphys. m/c
Large aggressive, >5cm lesion, permeative to mothern pattern of destruction, wide zone of transition, cortical dissolution,extremely large soft tissue mass, periosteal rx’n is rare
Dif.Dx:Liechtenstein’n rule...b/c wide charact.

57. Giant Cell Tumor Osteoclastoma
“M/c benign tumor of sacrum”
“M/c neoplasm of patella”
M/c in females
Age: 3th-4th decades
Sx’s: Pain,local tenderness w/swelling, dec. adjacent articulation
long tubular bones; m/c distal femur,prox.tibia,*distal radius & humerus
7% in spine(*sacrum)

58. Giant Cell Tumor=Osteoclastoma
Metaphyseal orig. w/epiphyseal extension to a subchondral location
Eccentric(60%) or soap-bubbly(40%); well defin. or poorly demarcated.Cortical thinning and expansion.Not common: sclerotic border; No matrix calcif.
Aggressive GCT often seen purely osteolytic
Differ.Dx:Chondroblastoma,ABC,Fibrous dysplacia,Eosinophilic granuloma,brown tumor of hyperthyrodism 58

64. Malignant Fibrous Histiocytoma
M/c in men
Age: any, m/c 5th to 7th decades
Sx’s: Pain & tenderness in assoc. w/large mass of soft tissue. Palpable tender mass.
ends of long bones.m/c in lower extremities. 50% near knee.M/c in tibia, femur, pelvis, humerus
Metaphyseal origin w/extension to epiphysis, diaphysis

65. Malignant Fibrous Histiocytoma
Permeative to motheaten pattern of bone destruction assoc. w/cortical erosion & soft tissue mass.Periostitis is limited.
Differ.Dx: *Fibrosarcoma, Osseous Metastasis 65

69. Simple (Unicameral) Bone Cyst
M/c in men
Age: <14yrs(80% of cases)
Sx’s: M/c asymp.; > than 60% pathological fracture
prox. humerus and femur. M/c in upper extremities. Also pelvis & calcaneus.
Active:within metaphysis,adjacent to growth plate; latent: diaphysis, away from growth plate

70. Simple (Unicameral) Bone Cyst
Metaphyseal lesion
Elongated, well-circumscribed, expansile, radiolucent, endosteal scalloping & fine septations(bubbly appearance);cortical disruption, soft tissue mass, periosteal rxn. No calcif.“Hinged fragment sign” + “Fallen fragment sign”
Calcaneal lesion:purely lytic,asymp,rarely frac- tured.Differ.Dx:lipoma,GCT,chondroblastoma
Diff.Dx:chondroblastoma,chondromyxoid fibroma,enchondroma,eosinophilic granuloma, fibrous dysplacia+ lipoma 70

75. Aneurysmal Bone Cyst “M/c benign tumor of clavicle” M/c in females
Age: 5-20yrs
Sx’s: Acute pain that rapidly progress, patholog. Fractures are common.Spinal lesions involving neural arch.
Long tubular bones(femur & tibia) & spine(T-L)
*Metaphyseal,can be extension to diaphys./epi
Eccentric,well-defined osteolytic,fine internal septae, prominent expansion + thinned cortices

79. Adamantinoma “Exceedingly infrequent” No gender predilection
Age: 10-40yrs
Sx’s: Localized pain assoc. w/swelling
mid-shaft of tibia
Differ.Dx’s: Fibrous dysplacia & ossifying fibromas

82. Ewing’s Sacroma “4th m/c 1ary malignancy of bone”
“M/c malignant lesion of pelvis in children”
M/c in men
Age:10-25yrs
Sx’s: Pain & Swelling localized,palpable mass in 1/3 cases, *simulate infection
M/c in long tubular bones (*femur), pelvis
*Diaphseal or metaphyseal(>charac. of osteosarcoma)

83. Ewing’s Sacroma
An ill-def. permeative to motheaten pattern of bone destruction, wide zone of transition,cortical desolution, *laminated or onion skin periostal rxn, prominent soft tissue mass. *Sunray pattern.
Differ.Dx’s: *osteosarcoma, lymphoma and infection

87. Hemangioma “M/c benign tumor of spine” M/c in females M/c >40yrs
Sx’s: M/c asymp.,assoc. w/painful swelling
M/c in spine(T-L) & skull(frontal/parietal)
Spine:”corduroy cloth”, mild osteopenia
Skull:“spoked wheel”, geographic, lytic defect w/dense spicules
MRI:high signal in both(T1+T2)
Differ.Dx:osteoporosis,Paget’s disease, renal osteodystrophy

93. Lipoma No gender predilection Age: all(4th decade-mean)
Sx’s: Aching pain aggravated by activity-60%, others: asymp.
M/c in fibula,femur,tibia + calcaneus
Metaphyseal m/c
Well-def.lucent, surround by thin sclerotic border,int. septae, dystrophic calcif. ”doughnut shaped”-central sclerosis + lucent zone around it
Diff.Dx:SBC,ABC,FD,enchondroma, clear cell chondrosarcoma