Osteoid osteoma mimicking chronic arthritis. Diagnosis by bone scintigraphy

The case of a patient with osteoid osteoma of the heel is presented. The patient was misdiagnosed and treated for four years as having arthritis. Osteoid osteoma was diagnosed by 99mTc-MDP bone scan that was performed for the evaluation of the arthritis. Plain radiography and magnetic resonance imaging (MRI) were negative for signs of arthritis. However, MRI when reevaluated after positive bone scintigraphy, was found positive for osteoid osteoma. This case underscores the value of bone scintigraphy for the diagnosis of osteoid osteoma.     

Osteoid osteoma simulating osteomyelitis: Differentiation with Tc-99m HIG scintigraphy

We present a case of osteoid osteoma with a history of mild pain, local swelling and point tenderness on the right lower leg. The diagnosis of osteoid osteoma was difficult due to the atypical clinical history and misleading radiological and bone scan findings. When it is difficult to differentiate an osteoid osteoma from osteomyelitis using CT, MRI or bone scan; HIG scintigraphy can be used to exclude an infection.     

Osteoid osteoma: operative confirmation of complete removal by bone scintigraphy

The high sensitivity of bone scintigraphy in detecting osteoid osteoma throughout the skeleton has been documented. Recently, radioactive surgical specimens of osteoid osteomas were studied with microradiography, autoradiography, and well-counter scintimetry and were shown to concentrate most of the radionuclide within the nidus of the lesion. These techniques also proved helpful to surgeons in achieving cure with conservative bone excision. We present two cases of osteoid osteoma, one of them recurrent, in which the patients were injected with bone-seeking agent just prior to surgery. The excised specimens were immediately imaged and the entire nidus was seen, confirming the complete removal of the lesion. This simple and rapid procedure is suggested whenever difficulty is anticipated in removal of an osteoid osteoma.     

Scintigraphic patterns in osteoid osteoma and spondylolysis

A retrospective review was performed of radionuclide bone scans and radiographs of 54 children with diagnoses of spondylolysis or osteoid osteoma/osteoblastoma. The findings indicate that skeletal scintigraphy shows imaging patterns that can be used to help distinguish these two conditions. Most cases of spondylolysis and all cases of osteoid osteoma or osteoblastoma demonstrated focally increased activity on the delayed skeletal scintigrams. Evaluation of the bone scan images obtained during the immediate postinjection period revealed intense activity with osteoid osteoma and osteoblastoma, but minimal or no abnormal activity in cases of spondylolysis. In addition, spondylolysis was the only condition that produced bilateral abnormalities in the pars interarticularis region in these children.     

Discrete synchronous multifocal osteoid osteoma of the humerus

 A 24-year-old patient is described who had a 4-year history of pain in the right upper arm, with distinct night pain, that responded to salicylates. From the findings on conventional radiography, bone scintigraphy and MRI a multifocal osteoid osteoma was suspected, with one focus in the cancellous region of the greater tuberosity and a second cortical focus at the proximal humeral diaphysis. The resection ’’en bloc’’ of both tumors and histological examination confirmed the diagnosis. The patient was painfree after the curative resection of the two osteoid osteomas. Osteoid osteoma is a frequently found benign bone tumor, accounting for approximately 11% of cases. In rare cases a multicentric occurrence has been described. A possible occurrence of more than one osteoid osteoma in a single bone, not verified histologically, has been reported only three times in the literature. In patients with scintigraphic and radiographic findings of two foci, discrete synchronous multifocal osteoid osteomas should be suspected.     

Osteoid osteomas of the hand. Report of three cases and review of the literature

Osteoid osteoma is infrequently localized to the hand. Initially the lesion causes unspecific symptoms, and the radiographic changes are discrete. Three cases were seen during a period of 5 years. Bone scintigraphy was a useful diagnostic tool, and CT facilitated the identification of the nidus. One of the lesions was a double nidus osteoid osteoma of the scaphoid bone. Only 12 instances of multifocal osteoid osteomas have been reported, none of which was localized to the carpal bones.     

Osteoid osteoma: CT-guided percutaneous treatment

Seven patients with presumed osteoid osteoma were treated with percutaneous destruction or drill resection with computed tomographic (CT) guidance. The diagnosis of osteoid osteoma was made on the basis of findings in the clinical history and results at plain radiography, bone scintigraphy, and CT. In four patients, histologic confirmation was obtained. Hospital stay lasted from 1 to 3 days. After 11-38 months of follow-up examinations, all patients were asymptomatic. The authors report this simple procedure as an alternative to the more traditional open surgery technique.     

Recurrent osteoid osteoma: a case report with imaging features

We present a case of a 14-year-old boy, who presented with pain in the left thigh region for 1 year. The pain exacerbated at night, waking up the child and was relieved by salicylates. On the basis of clinical history, conventional radiography, computerized tomography and bone scintigraphy, a diagnosis of osteoid osteoma was made. The tumor was completely excised, and there was complete remission of symptoms. Six months following surgery, the pain recurred in the same region. Conventional radiography revealed dense sclerosis at the surgical site. Three-phase skeletal scintigraphy showed a focal area of increased blood pool activity followed by intense focal uptake in delayed images, characteristic of osteoid osteoma. Computerized tomography confirmed the findings of skeletal scintigraphy.     

Osteoid osteoma in the differential diagnosis of persistent joint pain

We report 20 cases (13 male and 7 female), mean age 21 years) of juxta-articular osteoid osteoma. The distribution of affected joints was as follows: hip joint (7 cases), knee joint (2 cases), ankle joint (2 cases); iliosacral joint (2 cases), lumbar spine (2 cases), carpus (2 cases), shoulder (1 case), second metacarpal (MCP; 1 case) and first metatarsal (MTP; 1 case). The duration between the onset of symptoms and diagnosis varied from 8 months to approximately 4 years. In juxta-articular osteoid osteoma, the clinical picture and the radiographic findings are often atypical, and this may lead to misdiagnosis and delayed definitive treatment. In young patients with persistent undiagnosed pain, the possibility of an osteoid osteoma should be considered. When the clinical picture is suggestive but radiological findings are negative, we must proceed to further investigation with bone scintigraphy and computed tomography. These examinations should be repeated 1 year after the onset of symptoms because initially negative findings may become positive at a later date. When the diagnosis of an osteoid osteoma is confirmed, surgical excision leads to complete relief of the symptoms.     

Erroneous diagnosis of subperiosteal osteoid osteoma: value of imaging techniques?

A case of subperiosteal osteoid osteoma of the tibia misdiagnosed as stress fracture based on a history of multiple trauma and the results at MRI and bone scintigraphy is described. The nidus was well demonstrated at CT and the diagnosis was confirmed at histology. The role of different imaging techniques and their pitfalls are discussed.     

The diagnostic accuracy of MR imaging in osteoid osteoma

OBJECTIVE: To analyse the MR imaging appearances of a large series of osteoid osteomas, to assess the ability of MR imaging to detect the tumour, and to identify potential reasons for misdiagnosis. DESIGN AND PATIENTS: The MR imaging findings of 43 patients with osteoid osteoma were reviewed retrospectively and then compared with other imaging modalities to assess the accuracy of MR localisation and interpretation. RESULTS: The potential for a missed diagnosis was 35% based solely on the MR investigations. This included six tumours which were not seen and nine which were poorly visualised. The major determinants of the diagnostic accuracy of MR imaging were the MR technique, skeletal location, and preliminary radiographic appearances. There was a wide spectrum of MR signal appearances of the lesion. The tumour was identified in 65% of sequences performed in the axial plane. The nidus was present in only one slice of the optimal sequence in 27 patients. Reactive bone changes were present in 33 and soft tissue changes in 37 patients. CONCLUSION: Reliance on MR imaging alone may lead to misdiagnosis. As the osteoid osteoma may be difficult to identify and the MR features easily misinterpreted, optimisation of MR technique is crucial in reducing the risk of missing the diagnosis. Unexplained areas of bone marrow oedema in particular require further imaging (scintigraphy and CT) to exclude an osteoid osteoma.     

Computerized tomography and scintigraphy in the evaluation of osteoid osteoma

The authors report their experience of bone scintigraphy and computed tomography in 19 patients, with suspected osteoid osteomas, who underwent surgery. Basing on surgical findings, the role of these techniques in diagnosis, surgical planning and follow-up of osteoid osteoma is stressed and the results are compared with those of conventional radiography.     

CT of osteoid osteoma of the femoral neck: the value of oblique reformatting

An osteoid osteoma is a benign bone lesion which may involve the femoral neck. The lesions are distinctively osteoblastic, containing a central fibrovascular and osteoid nidus which often evokes substantial periosteal reaction occasionally making the diagnosis by conventional radiography very difficult. Computed tomographic evaluation of these lesions at other sites has been previously reported. I wish to emphasize the unique value of CT multiplanar reformatting in a patient with an osteoid osteoma of the femoral neck.     

Osteoid osteoma

Osteoid osteoma is a benign skeletal neoplasm composed of osteoid and woven bone that rarely exceeds 1.5 cm in greatest dimension. The lesion is most commonly located in the cortex of long bones where it is associated with dense, fusiform, reactive sclerosis. Less often, it may be cancellous, where reactive osteosclerosis is usually less intense and may be distant from the lesion. Cancellous lesions are frequently intraarticular (most often in the hip) and may be associated with synovitis and joint effusion. Rarely, osteoid osteomas occur in a subperiosteal location. Patients are usually young, and there is a strong male predominance. Pain is the most common symptom. Radiographs of patients with cortical osteoid osteoma are often diagnostic. Intraarticular lesions, however, may be subtle, and scintigraphy may be required to locate the lesion for subsequent computed tomography (CT). CT is useful to identify and precisely locate the lesion and to provide guidance for percutaneous localization or treatment.     

Osteoid osteoma: MR imaging revisited

To assess and compare with computed tomography (CT) the performance of magnetic resonance (MR) imaging in the detection of osteoid osteoma, and determine the features of this lesion on MR imaging. The prospective MR imaging and CT diagnosis of osteoid osteoma was determined from original radiology reports. MR images were assessed retrospectively with regard to the location and signal intensity of the nidus and surrounding bone marrow and soft tissue edema. These findings were correlated with the age of the patient, duration of symptoms, and drug therapy. Ten patients with histologically proven osteoid osteoma who underwent MR imaging were reviewed. All 10 lesions were correctly diagnosed at the time of MR imaging. None of the lesions was intracortical. Nine lesions were intra-articular. Two out of five patients with extracortical lesions had false negative CT preceding the MR study. Signal intensity of the nidus, marrow, and soft tissue edema on MR imaging were variable. Perinidal edema was most pronounced in younger patients and had no apparent relation to drug therapy. MR imaging reliably demonstrates the nidus of an osteoid osteoma, which has a variable appearance related to its position relative to the cortex of the bone. A predominance of cancellous osteoid osteomas are encountered in patients referred for MR imaging. Marrow edema in the vicinity of the lesion improves the conspicuity of the nidus. CT may fail to diagnose osteoid osteoma when the nidus is in a cancellous location, due to the lack of perinidal density alteration.     

Scintigraphy of spinal disorders in adolescents

Bone scintigraphy in adolescents is useful in helping to differentiate between developmental (atypical lumbar Scheuermann disease), infectious (discitis, osteomyelitis), neoplastic (osteoid osteoma, osteoblastoma), and traumatic (occult fractures, spondylolysis, pseudoarthrosis) disease of the spine. Double-phase (blood pool, delayed images) scintigraphy can characterize the pattern (i.e., linear in fracture, ovoid in nidus of osteoid osteoma). Single-photon emission computed tomography (SPECT) can be helpful in detecting the subtle presence of stress reaction (spondylolyses) not noted on routine planar scintigraphy and radiography. Bone scintigraphy is most beneficial when correlated with other imaging modalities in refining the diagnosis of spinal diseases.     

Osteoid osteoma of the second metatarsal bone diagnosed on MRI: A case report and literature review

Osteoid osteoma is a relatively common benign bone tumor that is most frequently seen on the appendicular skeleton in adolescents and young adults. Here we present the case of a 14-year-old boy presenting with a 10 month history of pain in his left foot which had been misdiagnosed as stress fracture due to its unusual clinical presentation. Magnetic resonance imaging of the left foot revealed a bone lesion with typical features of the osteoid osteoma on the distal part of the second metatarsal bone. The lesion was surgically removed and the diagnosis of osteoid osteoma was confirmed by post-surgical histopathologic examination of the resected section. The patient reported a substantial relief in his pain 4 weeks following the surgical operation.     

Intra-articular osteoid osteoma: diagnostic imaging in three cases

PURPOSE: To report our experience pertaining to three cases of intra-articular osteoid osteoma assessed by means of integrated imaging and review of literature. MATERIALS AND METHODS: Medical records, radiologic and nuclear medicine findings pertaining to three cases of intra-articular osteoid osteoma were retrospectively evaluated and compared with those of surgery. All the patients (2 males, one female; age range 8-38 ys) affected by intra-articular osteoid osteoma respectively of the elbow, tibio-talar joint and hip were evaluated by means of radiographic examination and Magnetic Resonance Imaging (MRI). SE T1-w and T2-w, GRE T2*-w, GRE 3D T1-w and STIR pulse sequences were used and axial, coronal and sagittal images were acquired. Two patients underwent CT scan. One patient underwent skeletal scintigraphy. All the patients underwent surgery. RESULTS: In 2 out of 3 cases plain radiography allowed the radiologist to suspect the presence of the lesion. In the remaining one, plain radiography failed to detect both the nidus and the perilesional osteosclerosis; nevertheless, a small osteochondral erosion of the humeral condyle suggested the presence of joint inflammation, thus leading to further investigation. CT scan well depicted the presence of the nidus and, in one case, the presence of joint effusion. MRI was always able to detect the nidus, which presented as lesion of low to intermediate signal in T1-w images, low signal in the T2-w images in one patient and high signal in the remaining two; in these latter STIR images showed high intensity nidus and edema of neighbouring cancellous bone. Furthermore, in all patients MRI clearly depicted joint effusion. Skeletal scintigraphy demonstrated both the lesion and the inflammatory involvement of neighbouring soft tissue. In all patients histologic specimen confirmed the diagnosis of osteoid osteoma with joint inflammation and synovitis. CONCLUSIONS: According to our results and literature data the pre-surgical diagnosis of osteoid osteoma is very difficult to achieve. Indeed, only the combination of clinical information and radiologic and nuclear medicine findings enables the radiologist to make the right diagnosis.     

骨样骨瘤的影像学诊断

目的分析骨样骨瘤的X线、CT及MRI表现,探讨其影像学特征。方法搜集经临床及病理证实的骨样骨瘤23例,男19例,女4例。所有病例均行X线检查,其中同时行CT检查者19例,行MR检查者7例,3种检查都进行者6例。分析骨样骨瘤的X线、CT和MRI表现,及其对瘤巢和瘤巢周围改变的显示能力,总结其特征性的影像学表现。结果23例病灶均显示一直径0.2～2.1cm大小不等的圆形或椭圆形瘤巢,边界清楚,边缘骨质不同程度硬化,骨膜反应,骨髓腔及软组织水肿或关节腔积液。24例X线平片17例显示瘤巢,19例行CT检查者均清晰显示瘤巢,7例行MR检查者5例可显示瘤巢,2例需结合X线及CT检查方能肯定诊断。X线、CT及MR对瘤巢的显示率分别为73.9%(17/23)、100%(19/19)及71.4%(5/7)。结论瘤巢是骨样骨瘤的特征性表现,CT检查是诊断骨样骨瘤最准确的方法,X线检查是诊断骨样骨瘤的重要方法,MR检查对显示瘤巢周围骨髓、软组织及关节腔情况非常敏感,仅凭X线或MR的表现易造成误诊、漏诊。     

Percutaneous Laser Photocoagulation of Osteoid Osteomas

Osteoid osteoma is a painful benign bone tumor. The curative treatment of this tumor consists of complete surgical or percutaneous excision of the nidus with immediate and dramatic relief of symptoms. Interstitial laser photocoagulation (ILP) is a low-invasive percutaneous technique of thermal destruction (coagulation) of deep-seated tumors elsewhere in the body, using low-power laser energy. The aim of ILP is the local destruction of osteoid osteoma without bone weakening. Twenty-two patients with osteoid osteoma were treated with percutaneous ILP of the nidus under computed tomography guidance. The laser energy was provided by a high-power semiconductor diode laser (805 nm) with a 400-&mgr;m optical fiber. Complete pain relief was obtained in 21 patients. Percutaneous ILP of osteoid osteoma seems to be a promising, simple, precise, and minimally invasive technique as an alternative to traditional surgical and percutaneous ablations.