Epithelioid osteoblastoma with secondary aneurysmal bone cyst and FOS gene rearrangement.

Epithelioid osteoblastoma, sometimes equated with aggressive osteoblastoma, is a variant of osteoblastoma that typically demonstrates more worrisome imaging and pathological features compared to conventional osteoblastoma. These more aggressive features can overlap with those seen in osteosarcoma, creating a diagnostic challenge for radiologists and pathologists. Recent identification of FOS and FOSB gene rearrangements in osteoid osteoma and osteoblastoma has allowed for greater diagnostic confidence following biopsy, but careful radiological-pathological correlation remains a key component for guiding appropriate management. Although the imaging features of conventional osteoblastoma have been previously described, there are limited examples in the literature of the imaging appearance of epithelioid osteoblastoma, and none with secondary aneurysmal bone cyst. In this case report, we detail the clinical, imaging, and histological characteristics of a proximal femoral epithelioid osteoblastoma which was pathologically confirmed by FOS and FOSB genetic testing. The initial imaging impression favored a malignancy, but when the biopsy results were correlated in a multidisciplinary fashion with the imaging, epithelioid osteoblastoma became the leading diagnosis which was subsequently genetically confirmed. This case emphasizes the value of multidisciplinary radiology-pathology correlation in routine practice.

Osteoid Osteoma of the Atlas in a Boy: Clinical and Imaging Features-A Case Report and Review of the Literature.

Osteoid osteoma is a benign osteoblastic tumor, quite uncommon in the spine. We report a case of an osteoid osteoma involving the atlas in a 6-year-old boy, who presented with suboccipital pain and torticollis. Initial radiological findings were ambiguous as magnetic resonance imaging showed mainly edema of upper cervical soft tissues. The subsequent computed tomography depicted a lesion of left lamina of C1. As conservative treatment failed, the lesion was surgically resected and the patient became pain free. To our knowledge, this is the first case of osteoid osteoma involving the atlas associated with abnormal soft tissue reaction reported in literature.

Osteoid osteoma in the ankle and foot. An overview of 50 years of experience.

BACKGROUND: The literature published about osteoid osteoma (OO) in the ankle-foot consists mainly on case reports. METHODS: We performed a retrospective study in which we analyzed demographic parameters, pain characteristics, treatment options and functional outcomes measured using the AOFAS and the SEFAS scales. RESULTS: We treated 17 patients with OO around the ankle-foot. Eighty-eight percent of patients had night pain that was relieved with NSAIDs. The bones most often affected were the talus and calcaneus. OO was diagnosed 21 months after the onset of symptoms. Mean follow-up was 17.3 years. The surgical techniques most used were curettage and curettage and bone grafting. There was a significant increase in AOFAS and SEFAS scores after surgery. CONCLUSIONS: Suspicion is the base of a prompt and a correct diagnosis of OO. The OO should be especially suspected in patients who present night pain that can be relieved with NSAIDs.

Unusual localization and presentation of osteoid osteoma mimicking juvenile spondyloarthritis: a case report.

BACKGROUND: Osteoid osteoma is a painful benign skeletal tumour of unknown aetiology. Most often it occurs in the long bones of extremities and responds well to nonsteroidal anti-inflammatory medications. However, unusual localization and atypical presentation of this tumour might present a diagnostic challenge, especially if symptoms mimic that indicative of juvenile spondyloarthritis. CASE PRESENTATION: A misdiagnosed ten-and-a-half-year-old girl with osteoid osteoma involving the distal phalanx of a little finger is presented. Her initial symptoms were pain and swelling of the little finger resembling dactylitis, while various imaging modalities showed signs of tenosynovitis, indicating a possible development of juvenile spondyloarthritis. Several trials of different non-steroid anti-inflammatory drugs gave no satisfactory results and ultrasound guided triamcinolone-hexacetonide injection provided only a short relief. Finally, almost three years after initial presentation, persistent clinical symptoms warranted repeated imaging that raised suspicion of an osteoid osteoma. Directed treatment with surgical intervention led to almost immediate and complete resolution of her symptoms. CONCLUSIONS: Osteoid osteoma should be suspected in case of a tender swelling of a digit in children and adolescents, regardless of initial imaging findings and clinical presentation. Early diagnosis and treatment of this benign condition can have a substantial impact on quality of life of patients and their families and protect them from many unnecessary diagnostic procedures and treatment.

An open-label, prospective, observational study of the efficacy of bisphosphonate therapy for painful osteoid osteoma.

OBJECTIVES: To assess the efficacy of bisphosphonate therapy on bone pain in patients with osteoid osteoma (OO) (main objective), and to describe bisphosphonate-induced changes in nidus mineralisation and regional bone-marrow oedema (BMO). METHODS: A prospective, observational study was conducted from 2011 to 2014. Patients with risk factors for complications of percutaneous or surgical ablation or recurrence after ablation, were offered once monthly intravenous bisphosphonate treatment until significant pain alleviation was achieved. RESULTS: We included 23 patients. The first two patients received pamidronate and the next 21 zoledronic acid (mean, 2.95 infusions per patient). Bisphosphonate therapy was successful in 19 patients (83%), whose mean pain visual analogue scale score decreased by 76.7%; this pain-relieving effect persisted in 17 patients (74%) with a mean follow-up time of 36 months. Computed tomography (CT) demonstrated a mean nidus density increase of 177.7% (p = 0.001). By magnetic resonance imaging (MRI), mean decreases were 38.4% for BMO surface area and 30.3% for signal intensity (p = 0.001 and p = 0.000, respectively). CONCLUSIONS: In 17/23 patients with painful OO managed conservatively with bisphosphonates, long-term final success was achieved. Bisphosphonates may accelerate the spontaneous healing of OO. KEY POINTS: • 19/23 patients with OO managed with bisphosphonates experienced significant pain relief • Pain relief was sustained in 17/23 patients, mean follow-up of 36 months • CT demonstrated a significant increase in nidus mineralisation • MRI demonstrated a significant decrease in bone marrow oedema • Bisphosphonate therapy may accelerate the spontaneous healing of OO.

Targetability of osteoid osteomas and bone metastases by MR-guided high intensity focused ultrasound (MRgHIFU).

PURPOSE: To retrospectively evaluate the suitability of MRgHIFU for osteoid osteomas (OOs) and bone metastases in patients who underwent minimally-invasive percutaneous thermal ablation. MATERIALS AND METHODS: One hundred and sixty-seven lesions (115 metastases and 52 OOs) treated percutaneously between October 2014 and June 2017 were retrospectively analyzed. Tumors were located in the spine or sacrum (54), pelvis (43), limbs (50), ribs (17) and sternum (3). Tumor volume, matrix, anatomical environment and need for protection of surrounding structures or consolidation were assessed. Cases were classified into three categories: (a) lesions suitable for MRgHIFU therapy alone; (b) lesions suitable for MRgHIFU if protection of surrounding structures and/or bone consolidation is performed; (c) lesions not suitable for MRgHIFU. RESULTS: Twenty-six (50%) of OOs were classified as suitable for MRgHIFU alone and 17 (32.7%) as suitable for MRgHIFU with hydro-dissection. Matrix of treatable OOs was sclerotic (19), lytic (15) or mixed (9), with mean volume 0.56 cm3. Forty-one (35.7%) of metastases were classified as suitable for MRgHIFU alone and 43 (37.4%) as suitable with hydro-dissection and/or consolidation. Matrix of metastases was sclerotic (13), lytic (37) or mixed (34), with mean volume 71.9 cm3. Mean depth of targetable lesions was 50.9 ± 28.4 mm. 97.7% of pelvic lesions and 94% of peripheral bone lesions were targetable by HIFU. 66.6% of spinal or sacral lesions were considered untreatable. CONCLUSION: MRgHIFU cannot be systematically performed non-invasively on bone tumors. Combination with minimally-invasive thermo-protective techniques may increase the number of eligible cases.

[Osteoid osteoma in the scaphoid bone as cause of radiocarpal pain in a 15-year-old patient]. / Osteoidosteom im Os scaphoideum als Ursache für radiokarpale Handgelenksbeschwerden bei einem 15-jährigen Patienten.

Osteoid osteomas are benign bone tumors which rarely occur in the hand and impose severe diagnostic problems. The course of the disease is often protracted before the patient receives an adequate surgical treatment. The case of an osteoid osteoma in the scaphoid bone of a 15-year-old patient is presented, who was completely symptom free after a true diagnostic odyssey by resection of the nidus and reconstruction by crest bone graft and spongiosaplasty.

Osteoid Osteoma: Benign Osteoblastic Tumor of the Lumbar L4 Transverse Process Associated with Radicular Pain: A Case Report.

Osteoid osteomas of the spine are benign bone tumors typically presenting with progressive pain without neurological deficit. This report presents a case of an osteoid osteoma in the lumbar spine associated with radicular pain. The patient, a young male athlete, presented with severe chronic nightly left low-back pain radiated to the ipsilateral lower extremity who failed to respond to physical therapy and analgesic medications. Initial radiologic examination was reported as normal, but closer inspection of the T1- and T2-weighted magnetic resonance image as well as technetium-99m total body bone scan and a computed tomography scan revealed a bony lesion in the left transverse process of the L4 vertebra consistent with the diagnosis of osteoid osteoma. A selective L3 nerve root block provided significant relief. Surgical excision of the osteoid osteoma resolved the symptoms. This case emphasizes the importance of early suspicion and diagnostic interventions in the detection and treatment of osteoid osteoma.

Treatment of Ribbing disease with 5-year follow-up and literature review.

Ribbing disease, or multiple diaphyseal sclerosis, is a rare diaphyseal sclerosis of unknown etiology. Patients with this pathology usually present with asymmetric pain limited to the lower extremities. Though all efforts are made to relieve the progressive pain associated with Ribbing disease, no medical or surgical treatments have been established yet. In this case report, we followed up a Ribbing case with sclerotic bone fenestration for 5 years. The radiological changes and the clinical effects are described, and the different Ribbing treatments are then briefly reviewed.

Progressive femoroacetabular impingement after complete excision of osteoid osteoma in adolescents: a report of two cases.

This article highlights that the long-term and serial follow-up of adolescents with osteoid osteoma should be considered, even after complete excision of the nidus owing to the possibility of the delayed onset or progression of femur head and neck deformities or osteoarthritis. It is important to recognize the sequelae of osteoid osteomas, such as bone edema and new bone formation, which can alter the normal anatomy of the proximal femur. We report two cases of osteoid osteoma in the proximal femur, which showed progressive hypertrophy of the femoral neck after excision of the nidus and subsequent cam-type femoroacetabular impingement (FAI), requiring additional osteochondroplasty procedures. Even though hip pain was relieved immediately after excision of the nidus in both cases, cam-type FAI developed during postoperative follow-up of 18 months (case 1) and 6.5 years (case 2). Hip pain subsided within 1 month of osteochondroplasty, and the full range of motion of the hip joint was achieved and was being maintained after postoperative follow-up of 1 year (case 1) and 6 months (case 2).

Osteoid osteoma of the temporal bone manifesting as first bite syndrome and a meta-analysis combined with osteoblastoma.

The objectives of this study were to describe a case of osteoid osteoma arising from the temporal bone manifesting only as first bite syndrome as the sole clinical symptom, to perform a meta-analysis of previously reported cases, and to differentiate the clinical characteristics of osteoid osteoma from those of osteoblastoma arising from the temporal bone. In addition to our case, articles addressing osteoid osteoma or osteoblastoma arising from the temporal bone were selected using PubMed, Embase, and the Japan Medical Abstracts Society database (1954 through 2014), with no language preference. The database was searched using the keywords ["osteoid osteoma" OR "osteoblastoma" AND "temporal bone"]. After critical review of 88 studies, 10 cases of osteoid osteoma and 29 cases of osteoblastoma were selected; therefore, including the present case, a total of 40 cases were eligible for qualitative analyses. The mean size of osteoid osteoma was 1.2 cm, which was significantly smaller than that of osteoblastoma (5.1 cm). Radiologically, osteoid osteoma was associated with a lower prevalence of extension into more than two anatomically categorized spaces in comparison with osteoblastoma (P < 0.01). Again, a lower prevalence of erosion of the outer and/or inner tables of the skull in the osteoid osteoma cases was noted (P < 0.05). Conversely, there were no significant differences in the prevalence of representative clinical symptoms, including pain and swelling. According to the present systematic review, osteoid osteoma and osteoblastoma are clinically uniform other than their size or extension.

Unusual cause of the thumb basal joint pain: osteoid osteoma of the trapezium.

The trapezium is rare site of osteoid osteoma development. The diagnostic challenge lies in its rare occurrence, and requires differentiation from various disease entities causing thumb basal joint pain. We report the case of a 29-year-old male who presented with severe thumb basal joint pain. He was initially treated for calcific periarthritis because of concomitant calcifications around the thumb basal joint, but had undiscovered osteoid osteoma. A high index of suspicion to a patient with wrist pain unresponsive to prior treatment is necessary for diagnosis of osteoid osteoma.

Intra-articular osteoid osteoma as a differential diagnosis of diffuse mono-articular joint pain.

BACKGROUND: The aim of this retrospective study was to investigate the frequency of intra-articular osteoid osteoma (iaOO) in a large study cohort and to demonstrate its clinical relevance as an important differential diagnosis of non-specific mono-articular joint pain. METHODS: We searched the registry for bone tumours of the University Medical Centre Hamburg-Eppendorf for osteoid osteomas in the last 42 years. Herein, we present three selected iaOO which were detected in the three major weight-bearing joints. Computed tomography (CT) or magnetic resonance imaging (MRI) scans were performed for initial diagnosis. RESULTS: Out of a total of 367 osteoid osteomas, 19 (5.2 %) tumours were localized intra-articularly. In all three presented tumours, a history of severe mono-articular pain was reported; however, the mean time to correct diagnosis was delayed to 20.7 months. Clearly, the nidus seen in CT and MRI images in combination with inconsistent salicylate-responsive nocturnal pain led to the diagnosis of iaOO. CONCLUSIONS: Rarely, osteoid osteoma can occur in an intra-articular location. In cases of diffuse mono-articular pain, iaOO should be considered both in large and smaller joints to avoid delays in diagnosis and therapy of this benign bone tumour.

Long-term clinical outcomes of dual-cycle radiofrequency ablation technique for treatment of osteoid osteoma.

PURPOSE: Radiofrequency ablation technique for treatment of OO including ablation time and temperature vary greatly between and within reported studies. This study evaluates the immediate and long-term efficacy and complication rate of a two sequential RFA technique for OO. MATERIALS AND METHODS: We retrospectively reviewed medical records and attempted interview follow-up for 25 patients treated with RFA for OO. Each treatment included 2 consecutive RFAs at 90 °C for 6 min with inter-ablation cooling to 40 °C and occasional inter-ablation probe adjustment. Additionally, we statistically compared the proportion of successful ablations using the DCRFA technique with published studies that utilized alternative OO ablation procedures. RESULTS: Long-term follow-up was obtained for 24 patients (96 %). Mean patient age at DCRFA was 17.2 years (range, 2.2-50.0 years). Mean time to follow-up was 60 ± 42 months (range 12-152 months). No acute DCRFA-related complications nor long-term recurrences were reported. All 24 interviewed patients reported partial relief of pre-procedural pain within 1 day of DCRFA and total relief within 1 week of DCRFA. One patient ultimately developed a major late complication (complex regional pain syndrome of the left ankle) after DCRFA of a cuboid lesion. Additionally, the DCRFA success rate was significantly higher when compared to two other published OO RFA treatment results. CONCLUSION: DCRFA employing two sequential 6-min cycles is an effective treatment of OO. The 100 % primary success rate, 0 % long-term recurrence rate, and low complication rate compare favorably and may be superior to results of prior reports.

[The intraarticular osteoid osteoma : A diagnostic and therapeutic challenge]. / Das intraartikuläre Osteoidosteom : Eine diagnostische wie therapeutische Herausforderung.

Intra- and, respectively, periarticular osteoid osteoma are accompanied by sympathical arthritis which itself can irreversibly destroy the cartilage of the joint. In contrast to other locations, intra- and periarticular osteoid osteoma are rare. Reactive and symptomatic accompanying arthritis may lead to irreversible cartilage destruction especially in chronic courses. Therefore early diagnosis and therapy is crucial. We present a case report and discuss these rare tumors by reviewing the literature.

Subtrochanteric osteoid osteoma: A misdiagnosed case complicated by a hip fracture.

A 34-year-old man with a subtrochanteric osteoid osteoma localized to the lateral cortex of the left femur is reported. The patient presented with mild spontaneous pain of the lateral thigh and knee. He refused a radiographic examination and was treated as a greater trochanteric pain syndrome for 9 months. He was then admitted with a transcervical fracture of the neck of the left femur after a fall from standing height. The fracture was fixed with 3 cannulated screws and healed uneventfully. His symptoms worsened after the first postoperative year. Eighteen months postoperatively the pain was dull, worsening at night, and relieved only with anti-inflammatory drugs, and he had a limp. New radiographs and tomograms were indicative of a lateral subtrochanteric osteoid osteoma with a subperiosteal localization. The lesion was treated successfully with surgical excision of a piece of reactive bone including the nidus.

Riddles in the diagnosis and treatment of osteoid osteoma in child foot: A concisive study.

BACKGROUND: Osteoid osteoma in child foot is very unusual. We investigate its polymorphism and difficulties in approach. METHODS: We retrospectively studied 12 children (7 girls, 5 boys) treated in our department from February 1995 until February 2010. Mean age was 12 years (range 8-16 years) and average follow up time 5 years (3-8 years). The lesion affected mostly the talus (8 cases), calcaneus in 3 and once the fourth metatarsal. En bloc excision of lesion was the surgical method of choice. RESULTS: Children's symptoms lasted average 2 years (14 months to even 4 years). Nocturnal pain and relief with NSAIDs occurred only in half cases. Atypical symptoms were hip referring pain, tenosynovitis of foot extensors and achilles' tendon atrophy. Complete cure and no recurrencies were noted. CONCLUSIONS: Diversity of symptoms and delay in diagnosis still remain troublesome and the absolute modality of treatment for child foot osteoid osteomas urges further investigation. Minimally invasive surgical techniques have recently emerged but orthopaedic surgeons must not forget that open excision remains the most safe and documented method for pediatric foot osteoid osteomas.

[Therapeutic effect analysis for open resection in osteoid osteoma around lesser trochanter of femur].

OBJECTIVE: To evaluate the radiological features of osteoid osteoma around lesser trochante of femur, and to analyze the outcomes of treatment with open surgery.
 Methods: From July 2013 to August 2015, 14 patients (9 males, 5 females) with osteoid osteoma around lesser trochanter were retrospectively reviewed. The ages of patients were 9-44 (average 20) years old. The duration of symptom was 3-36 (average 8) months. After the X-ray plain radiography, CT and MR, all patients underwent open resection. No intense exercise was allowed in the first three months after the operation.
 Results: There were 9 cases of cortical type, and 5 cases of subperiosteal type. The niduses were found by plain radiographs in 9 patients. By CT scan, the niduses were found in all 14 patients. The average pre-operative visual analogue scale (VAS) without NSAIDs was 6.5. One month after the operation, the average VAS was 0 for all patients. The follow up time for all patients was 9-34 (average 20) months. No recurrence, infection, neurovascular injury or fracture was found during the follow up.
 Conclusion: Open resection is a feasible method for osteoid osteoma around lesser trochanter of femur with satisfied outcome and low complication rate.

Atypical hip pain: coexistence of femoroacetabular impingement (FAI) and osteoid osteoma.

The objective of this article was to emphasize the importance of including less common causes of hip pain in a differential diagnosis, particularly when clinical and radiographic variables are atypical. This article presents the case of a 52-year-old patient with a history of progressive hip pain resulting from the coexistence of both a femoroacetabular impingement (FAI) and an intraarticular osteoid osteoma. The intraarticular osteoid osteoma was initially overlooked due to its unremarkable features on radiographic and resonance imaging. Consequently, the patient was surgically treated for FAI with only partial relief. An osteolytic nidus characteristic of osteoid osteoma was discovered only 1.5 years following surgery. The patient was subsequently treated for osteoid osteoma with anti-inflammatories, after which his pain began to resolve. The patient was completely pain free after 7 months. Level of evidence V.

[Osteoidosteoma. From diagnosis to treatment]. / Osteoidosteom. Von der Diagnose zur Behandlung.

An osteoid osteoma is a benign bone-forming tumor which usually presents in childhood and adolescence and is characterized by extensive nocturnal pain. Computed tomography (CT) is used to reveal the typical radiolucent nidus surrounded by a sclerotic reaction and in magnetic resonance imaging (MRI) a nidal enhancement and perifocal edema can confirm the diagnosis. Having shown excellent success rates radiofrequency ablation has become the treatment of choice which allows minimally invasive and precise destruction of nidal tumor tissue. By using thermal protection techniques and multiple ablation positions successful therapy of perineural tumors and niduses with diameters of more than 2 cm are possible.