FIBROUS DYSPLASIA=A SKELETAL DISORDER WHERIN MEDULLARY BONE IS REPLACED BY FIRO-OSSEOUS TISSUE
A DISORDER WHERE BONE IS REPLACED BY FIBROUS TISSUE
Bx: “CHINESE CHARACTERS”—BONEY TRABECULAE IN FIBROUS STROMA
MCCUNE ALBRIGHT SYNDROME—–PRECOTIOUS PUBERTY, HYPERPIGMENTATION, AND HYPOTHYROIDISM
MONOSTOTIC = 75% (PRIMARY LONG BONES, RIBS AND FEMUR)
POLYOSTOTIC = 25% (PRIMARILY UNILATERAL), FAMALE 3:1 MALE–
25% OF POLYOSTOTIC = ALBRIGHTS SYNDROME–SKIN PIGMENT (CAFE AU LAIT), PRECOCIOUS PUBERTY, AND FIBROUS DYSPLASIA
MAXILLA = PRIMARY BONE OF THE H & N
CHILDHOOD ONSET (ALMOST ALWAYS < 30)
FEMALE 3:1
RADIOGRAPHICALLY AND EXPANDED OSSEOUS LESION WITH AN EGG SHELL RIM
HISTO : GROUND GLASS, CHINESE CHARACTERS
LIKE PAGETS MAY DIGRESS INTO A VIRULENT OSTEOSARCOMA
DISEASE SEEMS TO STABILIZE AT PUBERTY—-MALIGNANT DEGENERATION < 1%—ASSOC WITH RT
Rx: CURRETAGE (25% RECURRENCE)
OSSIFYING FIBROMA
SIMILAR TO FIBROUS DYSPLASIA—BUT ONSET IS ABOUT 10 YEARS LATER
LESIONS ALSO HAVE OSTEOBLASTIC RIMMING