Display several atypical forms of clinical and radiological presentation of Osteoid Osteoma (OO),
which mimic other conditions,
showing how it is possible to differentiate them.
Also show the OO-mimicking lesions that may lead to diagnostic errors.
OO is a painful,
benign and common tumor,
accounting for 3% of all bone neoplasms.
in other words,
the tumor itself,
is small (1,2,3) and consists of osteoid matrix with variable mineralization,
osteoblasts and some osteoclasts surrounding the lesion,
interspersed by a vascular conjunctival stroma,
with inflammatory changes and reactional bone formation around the lesion (4,5).
The tumor is more prevalent in caucasians male adolescents and young adults between 7 and 25 years of age (6-11).
The typical clinical picture is intermittent pain...
Findings and procedure details
The definitive characterization of a lithic cortical nodule,
generally smaller than 1.0-2.0 cm,
with variable central nidus mineralization associated with sclerosis,
thickening and inflammatory changes of the surrounding bone is sufficient for the diagnosis (21,
especially when located in typical sites (12,
The OO nidus shows variable signal intensity on MRI with a target-like appearance,
since the non-mineralized vascular stroma has intermediate or high signal intensity on T2 and may present intense gadolinium enhancement,
while the mineralized portion presents low signal intensity on...
The clinical and radiological profile of Osteoid Osteoma can be very similar to other pathologies,
the knowledge of atypical forms of presentation,
differential diagnoses and active nidus seek,
if necessary with volumetric studies,
especially on CT,
avoid errors and delays in the diagnosis,
therefore allowing adequate treatment and better prognosis for patients.
1. Jaffe HL.
Osteoid osteoma: a benign osteoblastic tumor composed of osteoid and atypical bone.
Arch Surg 1935; 31:709–728.
2. Kransdorf MJ,
Moser RP Jr.
RadioGraphics 1991; 11:671–696.
3. Campanacci M (1999) Osteoid osteoma.
In: Campanacci M; Bone and soft tissue tumors,
Piccin Nuova Libraria Padova,
4. Filho GH,
In: Hartmann LGC,
Rodrigues MB; 2014,
5. Olvi L.G.,