Young adults are most frequently affected by OB, and patients typically seek medical attention for dull bone pain. Soft tissue and bony swelling may be noted at the site of the lesion. A general predilection for the axial skeleton has been observed [4], and up to 40% of cases involve the spine, mainly the vertebral arches of the lumbar region [5]. Nevertheless, OB may also develop in the appendicular skeleton, affecting the long bones of arms and legs or distal parts of the limbs [6].

OB exert local mass effects and accordingly, patients may present with spinal cord compression, radiculopathy, visual impairment and additional neurological deficits [7], stiffness and reduced joint motion ranges, among others. Lateral deviations of the spine and other deformities may be observed [8].

• Pain

  The tumor may cause pain, erosion, and resorption of native bone. Excision is the preferred treatment. [medical-dictionary.thefreedictionary.com]

  […] not as readily relieved by salicylates as in osteoid osteoma Pain may be present at rest, but does not usually have nocturnal worsening commonly associated with osteoid osteoma Patient may be asymptomatic, but pain is generally predominant feature Spinal [orthopaedicsone.com]

  The patient presented with a painful, firm, non-tender mass in his left thigh. The pain was worse at night and was temporarily relieved with NSAIDS. He had no fevers, night sweats, or weight loss. [ncbi.nlm.nih.gov]

  Clinical examination revealed a firm, painful, poorly differentiated swelling of the ulnar side of the wrist. The fingers and wrist were stiff and tender and the skin was bluish and shiny, suggesting a complex regional pain syndrome. [em-consulte.com]

• Swelling

  A 32-year-old female presented with a rapidly increasing swelling in left mastoid region for 6 months. During initial 2 months there was only pain in mastoid region which was followed by development of swelling. [ijpmonline.org]

  We present a case of a 19-year-old man with left shoulder pain for 1 year, with associated infraclavicular swelling for 8 months. Examination revealed a tender, bony, hard swelling measuring 3×4 cm. [ncbi.nlm.nih.gov]

• Weakness

  A 21-year-old male patient presented to our institution with a 4-month history of neck discomfort, radicular pain in the proximal right arm, and mild weakness of the right biceps and triceps muscles. [ncbi.nlm.nih.gov]

  This may produce pain that radiates into the arms or legs; weakness, numbness, or clumsiness in the arms and legs; or a loss of bowel and bladder control. Diagnosis Diagnosing osteoblastoma can be a challenge. [neurosurgery.columbia.edu]

  Osteoblastomas destroy normal vertebral bone and replace it with weak, abnormal bone. This process sometimes causes aching pain that is not relieved with NSAIDs (nonsteroidal anti-inflammatory drugs, like aspirin). [columbiaspine.org]

• Pathologist

  Collaboration between the clinician and pathologist is crucial and should take the tempo of evolution into account. The histopathological differences between these two tumour types deserve to be emphasized. [ncbi.nlm.nih.gov]

  Osteoblastomas may also have features that mimic malignant tumors, which often make it difficult for inexperienced surgical oncologists and pathologists to diagnose. [emedicine.medscape.com]

  Clues in clinical behavior and radiological examinations must be carefully assessed to guide the pathologist. [dovepress.com]

  It was later described as ‘osteogenic fibroma of bone’ by the American bone pathologist Louis Lichtenstein in 1952 14,15 and as ‘giant osteoid osteoma’ by D C Dahlin and E W Johnson, Jr 16 before the name osteoblastoma was suggested in 1956 again by Louis [radiopaedia.org]

  […] osteomas". aneurysmal bone cyst Changes characteristic of a secondary aneurysmal bone cyst or pathologic fracture may be present within some osteoblastomas, further adding to the problems of differential diagnosis. osteosarcoma It is important for the pathologist [humpath.com]

• Surgical Procedure

  The authors describe the clinical presentation, the surgical procedure for complete excision and stabilization, and results as of the 1-year follow-up. [ncbi.nlm.nih.gov]

  No early or late complications occurred after the surgical procedure. [mdpi.com]

  The following surgical procedures are among those used to treat osteoblastoma: En bloc resection: If more aggressive resection of the tumor is warranted, the operation will likely involve en bloc resection, which is the surgical removal of bone containing [childrenshospital.org]

  Treatment and prognosis Management is surgical with the selection of the surgical procedure depending on the location and aggressiveness 12. [radiopaedia.org]

  — which are used to remove microscopic tumor cells Bone grafting, a surgical procedure to replace missing bone with artificial graft material or cadaver bone Depending on the size and location of osteoblastoma removed, your child may be able to return [chop.edu]

• Diarrhea

  In 1994, the patient underwent upper and lower endoscopy because of weight loss and diarrhea, but the findings were not specific. During this evaluation, left hip pain developed. [healio.com]

• Fracture

  A 6-year-old male child presented with a type III pathologic fracture of the odontoid. The fracture healed but upon 6-month follow-up CT scanning, an expansile lesion was detected. [ncbi.nlm.nih.gov]

  In our patient, the fracture of the base of the fifth metacarpal bone occurred after a minor trauma, and the X-ray for this trauma showed regional bone demineralisation. This fracture could therefore be considered pathological. [em-consulte.com]

  This edition has new chapters on fracture callus; the growth plate and dwarfs; tissue/bone banking—bone grafts; and giant cell tumors and differential diagnosis of giant cell lesions. [books.google.com]

  Changes characteristic of a secondary aneurysmal bone cyst or pathologic fracture may be present within some osteoblastomas, further adding to the problems of differential diagnosis. [humpath.com]

  […] is in cervical spine Tender mass or soft tissue atrophy may be present Direct palpation often localizes a lesion, even when it cannot be seen on a plain radiograph Neurologic deficit rare, but can occur if there is compression of dura by pathologic fracture [orthopaedicsone.com]

• Back Pain

  Surgical resection of the lesion confirmed a benign osteoblastoma. 12 months follow-up revealed disappearance of right back pain. [ncbi.nlm.nih.gov]

• Muscle Spasm

  It is considered due to pain-provoked muscle spasm on the side of the lesion. Few researches about osteoblastoma combined with severe scoliosis have been reported. [ncbi.nlm.nih.gov]

  Spinal osteoblastomas may cause muscle spasms that produce scoliosis, or a bending and twisting of the spine. Scoliosis caused by muscle spasm is generally painful. [neurosurgery.columbia.edu]

  As the tumors grow, they may cause pain, swelling or muscle spasms. Is osteoblastoma cancer? No. Osteoblastoma is almost always benign (not cancerous). Where might I get osteoblastoma? Up to 2 in 5 osteoblastomas form around the spine. [my.clevelandclinic.org]

• Bone Disorder

  The book details the pathologic and radiologic characteristics of all bone and joint diseases, including arthritis, metastatic bone disease, osteoporosis, trauma, osteomyelitis, developmental bone disorders, and tumor-like lesions. [books.google.com]

• Spine Pain

  Pain, which is the most common symptom, may be similar to that produced by an osteoid osteoma (i.e., worse at night and relieved by nonsteroidal antiinflammatory drugs). In the spine, painful scoliosis or neurological deficit may be present. [brainscape.com]

• Suggestibility

  […] osteoblastomas which involve soft tissues and have radiological features suggesting malignancy. [ncbi.nlm.nih.gov]

  It had already been suggested in 19859 that malignant osteoblastomas and aggressive osteoblastomas could actually be osteosarcomas resembling osteoblastomas. [healio.com]

• Aggressive Behavior

  Osteoblastoma is a benign tumor with an aggressive behavior. The treatment is wide surgical resection, otherwise it continues to enlarge and destroy the bone and surrounding structures. [ncbi.nlm.nih.gov]

  Histological and immunohistochemical evaluation associated with clinical and imaging findings allowed to define the tumor as an aggressive variant of osteoblastoma and not osteosarcoma, despite the aggressive behavior. [journals.lww.com]

• Confusion

  Although most osteoblastomas are considered benign, a controversial aggressive variant has been described, which may cause diagnostic confusion with malignant tumors such as osteosarcoma. [ncbi.nlm.nih.gov]

  It should not be confused with the so-called “ossifying fibroma” which is apparently closely related to fibrous dysplasia and usually localized in the maxilla or the mandible (3). [pubs.rsna.org]

• Irritability

  Health News and Articles Comprehensive information about Diabetes, depression, weight management, osteoarthritis and more from MerckSource.com Health Resource Library - Information about Irritable Bowel Syndrome (IBS), high blood pressure, osteoporosis [web.archive.org]

  Acutely, the most common complication is skin irritation. Initial erythema may progress later to desquamation, especially in patients who also are being treated with cytotoxic drugs. [brainscape.com]

• Neurologic Manifestation

  manifestations Prevalence: Males: Females 2-3:1 Age: Patients are young, Median age 18 80% of patients are between 10 and 30 years old Sites: Spine (40% of cases; usually posterior elements) Long Bones (30%; Most arise from diaphysis or metaphysis; Epiphyseal [tumorsurgery.org]

  However, the tumor may be painful, and spinal lesions may be associated with scoliosis and neurologic manifestations. [en.wikipedia.org]

Diagnostic imaging is required to confirm the presence of an osseous mass, to determine its extension and to identify possibly compromised adjacent structures. Plain radiography and computed tomography are most commonly employed and yield reliable results. Here, OB present as discrete lesions comprising both lytic and sclerotic regions [9]. Soft tissue involvement may be better assessable applying other imaging techniques.

A histopathological examination of biopsy specimens is crucial for the diagnosis of OB. In this context, it is important to obtain representative samples that ideally measure several millimeters in size. Fine-needle aspirates are usually insufficient. OB are hypocellular, mineralized tumors consisting of irregular, largely immature trabecular bone [7]. Giant cells may be present. There are no apparent differences between central and peripheral areas of the tumor. Lesions are well demarcated, and this feature helps to distinguish OB from osteosarcoma. However, the transition from benign OB to malignant osteosarcoma is smooth and aggressive types of OB have been described [10].

Based on radiological findings and histopathological analyses alone, the distinction between OB and osteoid osteoma may pose a major challenge. Still, a precise diagnosis is of major prognostic and therapeutic relevance: OB have considerable malignant potential, may show locally aggressive behavior,and recurrence is more likely than in patients diagnosed with osteoid osteoma [5]. Clinical criteria should be considered to support a tentative diagnosis of either bone tumor [4]:

• OB usually develop in the axial skeleton, while osteoid osteomas primarily affect the long bones of the limbs.
• Persistent bone pain is characteristic of OB, whereas osteoid osteoma patients frequently experience pain that worsens at night.
• In patients suffering from osteoid osteoma, pain may be relieved by salicylates, but this is rarely the case in individuals suffering from OB.
• Both are most commonly diagnosed in young adults but may affect patients of any age.

Conservative treatment with anti-inflammatory medications before referral was unsuccessful. The authors present the diagnostic difficulties and the treatment that was applied: proximal row carpectomy. [ncbi.nlm.nih.gov]

Osteoblastoma: When the Treatment Is Not Minimally Invasive, an Overview. [mdpi.com]

This case delineates the difficulties in diagnosing this tumor, the challenges and problems encountered during its surgical management, and the favorable prognosis after adequate treatment. [ncbi.nlm.nih.gov]

In general, osteoblastoma has a good prognosis, and patients are often cancer-free after surgical treatments of intralesional curettage or marginal en bloc resection. [pubmed.ncbi.nlm.nih.gov]

Total resection should be advocated whenever possible, due to good prognosis and relatively low recurrence, even in the recurrent cases. [indianjotol.org]

In conclusion, the differential diagnosis for vertebra plana is extensive and we add spinal osteoblastoma as another etiology to the existing list. [ncbi.nlm.nih.gov]

Epidemiology Incidence relatively rare less common than osteoid osteoma Demographics males > females (2:1) majority of patients 10-30 years of age Anatomic location most common in posterior elements of spine Etiology Genetics unknown Associated conditions [orthobullets.com]

The exact etiology of osteoblastoma is unknown. Epidemiology In the United States, osteoblastoma accounts for approximately 1% of all primary bone tumors. [emedicine.medscape.com]

Etiology of osteoblastoma is unknown; however it is considered to be a true neoplasm of bone (3). Itmost commonly affects vertebral column, sacrum, calvarium, long bones and small bones of hand and feet. [ijp.iranpath.org]

Basic demographic and epidemiological data were recorded. Tumor characteristics, surgical parameters, and clinical follow-up data were noted. RESULTS: The mean follow-up was 21.9 months. [ncbi.nlm.nih.gov]

Epidemiology Incidence relatively rare less common than osteoid osteoma Demographics males > females (2:1) majority of patients 10-30 years of age Anatomic location most common in posterior elements of spine Etiology Genetics unknown Associated conditions [orthobullets.com]

Epidemiology In the United States, osteoblastoma accounts for approximately 1% of all primary bone tumors. [emedicine.medscape.com]

The epidemiological aspects, size of the disease and site of onset, symptoms, surgery type, indications, and results are reported for every case. Results: all treatments were based on a preoperative diagnosis; pain was constant in all cases. [mdpi.com]

The pathophysiology of symptom development, evaluations, and management are presented. Because of the close proximity of the osteoblastoma to the vertebral artery canal, the artery suffered a minor laceration intraoperatively. [ncbi.nlm.nih.gov]

[citation needed] Pathophysiology[edit] The cause of osteoblastoma is unknown. [en.wikipedia.org]

Pathophysiology and Etiology Regardless of where osteoblastomas originate within the musculoskeletal system, they are composed of numerous osteoblasts that produce osteoid and woven bone. [emedicine.medscape.com]

Preoperative embolization was performed to reduce intraoperative bleeding and to prevent intraoperative injury of the vertebral artery. A pathologic examination showed osteoblasts suggestive of osteoblastoma. [ncbi.nlm.nih.gov]

Osteoblastoma (OB) is a rare type of neoplasm, accounting for approximately 1% of primary bone tumors [1]. OB are benign tumors originating from osteoblasts, and they are characterized by their ability to produce osteoid. Thus, they form large masses with diameters exceeding 2 cm that exert local mass effects on adjacent tissues. Because OB most frequently affect the axial skeleton, central nervous system compromise is frequently seen in affected individuals. Furthermore, OB have been reported to undergo malignant transformation [2]. Still, OB patients generally have a good prognosis and most of them are cured by means of a complete surgical resection of the neoplasm [3].

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2. Kraft CT, Morrison RJ, Arts HA. Malignant transformation of a high-grade osteoblastoma of the petrous apex with subcutaneous metastasis. Ear Nose Throat J. 2016; 95(6):230-233.
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6. Li Z, Zhao Y, Hou S, Mao N, Yu S, Hou T. Clinical features and surgical management of spinal osteoblastoma: a retrospective study in 18 cases. PLoS One. 2013; 8(9):e74635.
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9. Pelargos PE, Nagasawa DT, Ung N, et al. Clinical characteristics and diagnostic imaging of cranial osteoblastoma. J Clin Neurosci. 2015; 22(3):445-449.
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