Bone Pathology 1 Practical 1

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

Enostosis= “Bone Island” =Enostoma At all ages,m/c in adults M/c asymp. In all skeleton, except skull. M/c @ 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

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

Osteoid Osteoma M/c in male Age: 10-25yrs Sx.’s: Pain > severe @ 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 scoliosis @ concave side.

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

Nidus

Osteoblastoma M/c in males Age: 10-30yrs. Sx.’s: Local pain; in spine lesions: muscle spasm,scoliosis & neurolog. Sx.’s M/c @ 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

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

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 M/c @ long tubular bones: *femur(40%),tibia(16%),humerus(15%) Around knees- 50-70% cases *Metaphyseal, extension to diaph/epiphys.

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

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

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

Multiple Hereditary Exostosis

Enchondroma “M/c benign tumor of the hand” No gender predilection Age: 10-30yrs Sx.’s: m/c asymp., painless swelling 40-65% @ 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

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

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

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

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.; m/c @ pelvis + prox. femur-50%cases; also in humerus, scapula,ribs, bones around knee

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

Fibrous Cortical Defect Non-Ossifying Fibroma M/c in males Age: FCD:4-8yrs; NOF:8-20yrs 90% @ 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

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.

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. ROM @ adjacent articulation >75% @ long tubular bones; m/c distal femur,prox.tibia,*distal radius & humerus 7% in spine(*sacrum)

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

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. 75%@ 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

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

Simple (Unicameral) Bone Cyst M/c in men Age: <14yrs(80% of cases) Sx’s: M/c asymp.; > than 60% pathological fracture 75% @ 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

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

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

Adamantinoma “Exceedingly infrequent” No gender predilection Age: 10-40yrs Sx’s: Localized pain assoc. w/swelling 85% @ mid-shaft of tibia Differ.Dx’s: Fibrous dysplacia & ossifying fibromas

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)

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

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

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