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Many benign bone tumors are painless and are incidental findings on radiographs.
Osteoid osteoma is a relatively common benign tumor. It frequently causes pain that is worse at night and is exquisitely responsive to nonsteroidal anti-inflammatory drugs (NSAIDs).
Nonossifying fibromas (NOF) are common fibrous lesions. They are often incidental findings but can also cause chronic pain.
Osteochondromas tend to present as a bony, nonpainful mass. Radiographically they appear as sessile or pedunculated lesions of the long bones.
Patients with enchondromas may present with a mass or pathologic fracture, but most are asymptomatic. The hands are most commonly involved.
Solitary bone cysts in the lower extremity are prone to fracture and require excision.
Aneurysmal bone cysts (ABCs) commonly involve the long bones. They are associated with rapidly progressive pain and swelling and can cause significant morbidity.
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Osteoid osteoma is a very common benign tumor of bone and accounts for 2% to 3% of all bone tumors and 10% to 20% of benign bone tumors.1It is two to three times more frequent in males and is most common between 5 and 20 years of age. Osteoid osteoma most commonly involves the long bones of the legs but may occur in any bone including the hands and the spine where it is the most common cause of painful scoliosis in skeletally immature individuals.2
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Pain is the most common presentation of osteoid osteoma. It is mediated by the proliferation of nerve endings in the tumor and a high level of prostaglandins in the nidus, which accounts for the exquisite responsiveness of the pain to NSAIDs.3 The pain is usually mild and intermittent but then becomes continuous and severe and tends to be worse at night. Patients may have point tenderness, a swollen limb, and/or a tender palpable mass; or they may present with a painless limp. Osteoid osteomas in the joints may mimic arthropathy whereas those in the spine may present with scoliosis, torticollis, hyperlordosis, or kyphoscoliosis. Osteoid osteomas that are close to the growth plates may lead to growth disturbance and limb-length discrepancies or angular deviations. If the diagnosis of osteoid osteoma is delayed, patients may present with chronic pain or limping as well as atrophy of the affected limb.
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Clinical history and radiographs are usually sufficient to diagnose osteoid osteoma (histologic confirmation is not necessary). The typical radiographic appearance of a cortical osteoid osteoma is of a small (<1 cm)radiolucent round or oval area of osteolysis (nidus), surrounded by a regular ring of bony sclerosis (Fig. 111-1). The entire entity rarely exceeds 1.5 cm. In some cases, the center of the nidus may have an irregular nucleus of bone density giving a cockade appearance. The bone circumference may be increased. Cortical diaphyseal lesions may produce an oblong thickening to one side of the shaft. In these lesions, the nidus lies at the center of the thickening and may be contained within the primary cortex or oriented toward the endosteal ...