- See: Bone Tumor Menu
- benign osseous tumor usually less than 1.5 cm in diameter, comprising 11% of all benign bone tumors;
- no cases of malignant transformation has been reported;
- occurs primarily in adolescents and less often in children;
- it is rare in patients over age 40 yrs;
- presenting symptom is well localized pain which may be more severe at night & is relieved by aspirin or other prostaglandin inhibitors;
- because osteoid osteoma is a vascular tumor, substances which cause vasodilitation such as alcohol may precipitate an acute pain crisis;
- most common site is proximal femur, & diaphysis of long bones;
- less often: foot (talus, navicular, or calcaneus) & in posterior spine
- osteoid osteoma of the spine:
- may be an occult lesion;
- most often located in the posterior elements;
- may not produce a bony reaction;
- may lead to painful secondary scoliosis.
- bone scan is a useful test;
- Computed tomography of axial skeletal osteoid osteomas.
- Osteoid-osteoma and osteoblastoma of the spine.
- Osteoid osteoma of the spine. BA Arbarnia et al. Orthop. Trans. Vol 6. 1982. p 43.
- hand: diff dx: osteomyelitis, AVN, synovitis, TB, and RA;
- Exam: note whether there is a palpable lumb of reactive bone;
- intense bony rxn to small nidus is hallmark of osteoid osteoma, however, may be difficult to see on x-rays;
- look for oval radiolucent nidus only 3-5 mm in diameter which surrounded by disproportionally large, dense reactive zone;
- although usually located in cortex, nidus may occur subperiosteal and endosteal regions;
- Radiographic Diff Dx:
- Garre's osteomyelitis (chronic sclerosing osteomyelitis)
- Brodie's abscess
- Stress fracture
- Synovial herniation pits (Pitt's pits)
- common lesions in individuals with femoroacetabular impingement;
- tumor simulators and are incidentally identified on radiographs
- Herniation pit of the femoral neck.
- Symptomatic herniation pits of the femoral neck: anatomic and clinical study.
- Bone Scan:
- bone scans usually shows moderate or intense radioisotope uptake;
- CT Scan:
- nidus is best localized w/ CT - tell radiologist of diff dx:
- cuts should be 1-2 mm to visualize the nidus
- the window settings of the CT scanner should be adjusted so that
the dense reaction around the lesion does not obscure the
small low density nidus;
- Histologic Examination:
- nidus composed of thick vascular bars of osteoblastic tissue surrounded by vascular fibrous tissue finally surrounded by mature reactive cortical bone;
- Differential Dx:
- is usually larger than osteoid osteoma;
- osteoblastoma usually does not produce an intense bony reaction;
- osteoid osteoma may resolve spontaneously w/ time (especially when located in the hand), however, most patients prefer not to
wait 2 to 4 years for resolution;
- when nidus is located in a low stress area such as metaphysis, treatment should consist of en bloc excision w/ surrounding small
block of reactive bone;
- tetracycline localization:
- using tetracycline at a dosage of 4 mg/kg, four times daily, 2 days preoperatively, the nidus will have a golden yellow fluorescence;
- the OR must be dark inorder to see it;
- percutaneous radiofrequency coagulation:
- involves percutaneous insertion of a biopsy needle under CT scan guidance;
- a tissue biopsy is taken in order to prove that the needle is properly located;
- then a radiofrequency electrode with a 5 mm exposed tip is introduced thru the cannula;
- the electrode is connected to a radiofrequency generator which raises the temperature of the tip to 90 deg C (which is
maintained for 6 minutes);
- as noted by Rosenthal et al 1998, results of this technique are comprable to the standard open technique;
- other options include, shaving of overlying margin of reactive bone until nidus is visible as red spot that can be removed w/ curettage;
- ensure that 1-2 mm of normal bone is curretted out as well
Subungual Osteoid Osteoma of the Distal Phalanx of the Great Toe
Osteoid-osteoma: intraoperative tetracycline-fluorescence demonstration of the nidus.
Osteoid osteoma. The double density sign.
Osteoid osteoma. Diagnosis, localization, and treatment.
Medical management compared with operative treatment for osteoid-osteoma.
Minimally invasive surgery for osteoid osteoma of the proximal femur.
Staging and treatment of primary and persistent (recurrent) osteoid osteoma. Evaluation of intraoperative nuclear scanning, tetracycline fluorescence, and tomography.