Non-ossifying fibroma (fibrous cortical defect)

• Lucent fibrous tissue lesion (benign) inside bone cortex.

• Mostly accidentally discovered by x-ray.

• Seen in children and may disappear spontaneously with time during growth.

• X-ray shows eccentrically located lucent small defect in the bone

• Seen mostly in the cortex of the metaphysis of long bones.

• Rarely if large may cause pathological fracture.

• Usually does not need treatment unless there is pathological fracture.

Fibrous dysplasia

• Developmental disorder whereby normal bone is replaced by fibrous tissue with flecks of osteoid.

• It may affect one bone (monostotic) or multiple bones (polystotic).

• The lesion may be very large causes bone expansion and cortical thinning with progressive deformity and sometimes pathological fracture.

• Lesions occur in metaphysis & diaphysis, proximal femur is a common site it gives characteristic deformity called (shepherd’s-crock deformity( الراعي .عصا

• X-ray shows lucent cystic lesion sometimes large and multilocular with bone expansion and cortical thinning it contains multiple calcific spots giving the ground-glass appearance, there is always possible deformity or pathological fracture.

• About 5-10% of polyostotic forms get malignant, while only rarely occurs in monostotic lesions.

• Treatment depends on tumor size and possible deformity;– Small lesions may need no treatment, just

follow up.– For larger lesions we do curettage and bone

graft or cement.– Sometimes we need internal fixation. – Deformities may need corrective osteotomy.– Always there is tendency for recurrence.

Osteoblastoma (giant osteoid osteoma)

• It’s benign and similar to osteoid osteoma but its larger and more cellular.

• It occurs in young adults, males more than females.

• Its commoner in the spine and flat bones& usually presents as pain or muscle spasm.

• X-ray shows well-defined lytic lesion surrounded by thin zone of sclerosis, it may contain flecks of calcification.

• Treatment is by local excision and bone graft.

• Always there is tendency for recurrence and malignant changes are reported.

Bone cysts(tumor like conditions)

Simple bone cystAnurysmal bone cyst

Simple bone cyst (solitary or unicamerial bone cyst)

• It’s not a tumor but it’s a tumor like condition.

• Common in upper humerous, femur and tibia.

• Seen in children up to the age of puberty.

• Presents as local pain or pathological fracture.

• Occurs in the metaphysis and directed towards diaphysis.

• X-ray shows translucent cystic lesion in the metaphysis and shaft of bone with bone widening and cortical expansion and thinning with possible pathological fracture.

• It may show bridges of calcification inside as a result of healing of micro fractures that commonly occurs,

• by this way it may gradually disappear and heals later in life;

• sometimes we use this criteria as a method of treatment by frequent aspiration and local steroid injections aiming at induction of such micro fractures that aids healing

• Small cysts treated as above, for larger cysts we do curettage and bone graft.

Aneurysmal bone cyst • Tumor-like cystic lesion forms of multiple

cavities full with blood.

• Mostly seen in spine or eccentrically located in the metaphysis of long bones of young adults.

• X-ray shows well-defined irregular eccentric lucent lesion in the metaphysis that does not reach the articular surface, it may show ballooning, cortical widening and thinning.

• Important differential diagnosis is giant cell tumor.

• Treatment is by curettage and bone graft.

Giant cell tumor (osteoclastoma):

(Sometimes-malignant tumor - Intermediate tumor)

Pathology:• This tumor contains multinucleated giant

cells and large number of stromal cells.

• Its soft friable tumor seen in the soft cancellous subarticular bone and never reach the articular surface.

• It’s a tumor of young adults occurs after bone maturity in the epiphysial region.

• Its intermediate type of tumor (neither benign nor malignant)–About 1/3 of it remains benign ,–1/3 is locally aggressive,–1/3have distant metastasis.

Clinical features:• Patient aged 20-40.

• There is pain or swelling near a joint, 10% presents with pathological fracture.

• O/E vague swelling at the bone end and signs of joint irritation.

X-ray:• Rarefied area of the bone end reaching

just below the articular surface.

• Eccentric lesion with bone expansion and ballooning with cortical thinning, sometimes pathological fracture.

• There may be calcific trabiculations inside the lesion giving it the commonly known saop-bubble appearance.

Treatment:• For well-defined small and rather

benign lesion, we can do curettage and burr-down with bone graft.

• Larger more aggressive lesions may need local excision and bone graft or prosthetic replacement.