Benign bone-forming lesions: osteoma, osteoid osteoma, and osteoblastoma. Clinical, imaging, pathologic, and differential considerations

Osteoid Osteoma of the Occipital Condyle in Adolescents: Surgical Resection Under Navigation

This article reports a 12-year-old male with occipital condyle osteoid osteoma, presenting with neck pain and limited motion, unresponsive to conservative treatment. CT revealed a right condylar lesion. Surgical excision via a right paramedian suboccipital incision achieved complete recovery, confirmed by pathology and 3-month follow-up.

Impact of reactive sclerosis on outcome of MR-HIFU for osteoid osteomas

OBJECTIVES

To evaluate the influence of clinical and procedural factors, particularly the thickness of reactive sclerosis, on clinical outcome of MR-guided high-intensity focused ultrasound (MR-HIFU) for the treatment of symptomatic osteoid osteomas (OO) of the extremities.

MATERIALS AND METHODS

18 consecutive patients (median age 19.5y) with symptomatic OO of the extremities eligible for MR-HIFU were enrolled in this ongoing prospective study (German Clinical Trials Register; nr. DRKS00015448). The Functional Assessment of Cancer Therapy - Bone Pain (FACT-BP) score was used for evaluation of symptoms and quality of life parameters at 1-week, 2-week, 1-month, 6-month and 12-month follow-up (FU) after intervention. MRI was performed prior as well as, 6 and 12 months after intervention. Assessment included procedural and imaging parameters, with a specific focus on the thickness of the reactive sclerosis surrounding the nidus.

RESULTS

Symptoms and quality of life parameters significantly improved between baseline and all FUs on the FACT-BP (mean score at baseline: 29.7; at 6-month-FU: 5.5; at 12-month-FU: 3.4, all p < 0.01). A strong correlation was found between scores of FACT-BP and the thickness of reactive sclerosis surrounding the nidus (r = 0.62 at 6-month-FU; p = 0.006) with an optimal cutoff of 0.6 cm identified for predicting a good clinical outcome.

CONCLUSION

MR-HIFU is an effective method for the treatment of symptomatic osteoid osteomas of the extremities in pediatric and adult patients, with the thickness of reactive sclerosis surrounding the nidus being a relevant factor influencing patient outcomes and emphasizing its importance in MR-HIFU assessment and planning.

Osteoid osteoma and osteoblastoma of the cervical spine in the pediatric population: analysis of the literature and experience with four operated cases

BACKGROUND AND AIM

Osteoid osteoma (Oo) and osteoblastoma (Ob) are rare primary bone tumors with a higher prevalence in the second decade of life. Treatment can be conservative, but in cases of spinal location, resective surgery is of great importance but may be challenging.

MATERIAL AND METHODS

We report four pediatric cases of Oo and Ob managed in our unit, with different locations at the level of the cervical spine. All four patients had a common complaint of persistent and progressive neck pain, two reported worsening pain at night, and three underwent NSAID treatment attempts without significant response. The radiological examination revealed a lesion of bone origin in the cervical spine in all cases: two at the pediculolaminar complex, one at the laminar, and one at the level of the C2 body and odontoid. A comprehensive literature review was carried out by comparing the data and a discussion of the cases.

RESULTS

A complete surgical resection was performed by a posterior approach in three patients and a transoral in one. A hard neck collar under molding ensured postoperative stability in all cases. Control imaging studies demonstrated satisfactory lesion resection. Histologically, three cases were an osteoblastoma and one an osteoid osteoma. Control imaging studies demonstrated satisfactory lesion resection with good late bone reconstruction. Ultimately, none showed late instability requiring fixation. The mean follow-up time is 36 (16-63) months. None had a recurrence nor late instability requiring fixation.

CONCLUSION

Treatment of pediatric cervical spine of osteoid osteoma and osteoblastoma should seek a complete resection. In regions with a risk for secondary instability, the preservation of capsule-ligamental structures and temporary orthopedic immobilization can allow bone regeneration with no need for fixation. Extended follow-up is recommended especially in very young children to avoid late instability.

A rare cause of shoulder pain: Osteoid osteoma of the scapular glenoid treated with cryoablation

We report a case of an osteoid osteoma at the scapular glenoid that was treated with cryoablation. The patient presented with shoulder pain with subsequent CT and MRI imaging findings suspicious for an osteoid osteoma. The patient complained of persistent pain despite medical treatment and was referred to interventional radiology for consideration of ablation. CT-guided biopsy confirmed the diagnosis of osteoid osteoma and the patient underwent cryoablation of the lesion in the same session. The patient reported a substantial relief in her pain at a follow-up 4 weeks after the procedure. MRI performed 8 weeks after the procedure also confirmed radiographic remission of the lesion.

Olecranon fossa osteoid osteoma excision through arthroscopy: surgical technique

In the elbow joint, occurrences of intra-articular osteoid osteoma are uncommon. We detail the case of a 21-year-old male who experienced pain, inflammation, and a restricted ability to move his elbow. For a few months, the diagnoses was missed and the patient was treated for idiopathic synovitis. After a contrast MRI, the tumor was revealed. During an arthroscopic examination of the elbow, a distinct red lesion was observed after the removal of the pale reactive bone in the olecranon cavity. This was subsequently removed in its entirety with the aid of a specialized bone tool. Histopathology confirmed the diagnosis of osteoid osteoma. Remarkably, the individual reported alleviation from the symptoms just a day following the operation and regained full range of motion 5 weeks after the surgery. This case underscores the efficacy of arthroscopy in addressing intra-articular osteoid osteoma, with a focus on accurately pinpointing the lesion.

Remodeling of Lumbar Spinal Osteoid Osteoma Resected With Microscopic Surgery in a 15-Year-Old Basketball Player: A Case Report

This case report focuses on a 15-year-old competitive-level high school basketball player who experienced chronic low back pain. Diagnostic imaging revealed osteoid osteoma in the L5 posterior element, causing osteosclerotic deformity of the left lamina and more inferior facet. To return him to the condition of sports activity, less invasive surgery of microscopic tumor resection with autologous bone grafting was planned instead of CT-guided ablation, which can cause thermal injury to nearby tissues. This procedure could preserve spinal structures, including the facet, pedicle, and paravertebral muscles. The day after surgery, the patient experienced a complete resolution of lower back pain. He gradually resumed light exercise two months postoperatively. Three-month follow-up CT imaging revealed bone remodeling at the resection site, to return to complete basketball activities. Over five years, no tumor recurrence or symptoms were observed, and he maintained his competitive activity level.

Osteoid Osteoma of the Trapezium: A Rare Case Report and Literature Review

Osteoid osteoma is the most common benign osteogenic bone neoplasm. Osteoid osteomas are typically located in the metaphysis and diaphysis of long bones, especially the tibia and femur. However, less common sites of the skeleton can be affected as well, including carpal bones. Among carpal bones, the scaphoid and the capitate are the most affected. Osteoid osteoma of the trapezium is an extremely rare entity, with only seven cases reported in recent literature. We present a case of a 29-year-old male with persistent left wrist pain who was diagnosed with an osteoid osteoma of the trapezium bone. The diagnosis was based on the patient's history, clinical examination and findings from the CT scan, MRI, and plain radiographs. The patient was treated with an excision biopsy with no additional bone grafting. After a follow-up period of 12 months, no pain or signs of recurrence were present. We conducted a literature review to elucidate the clinical presentation as well as the proper diagnostic tools and therapeutic methods for this rare occurrence.

Osteoid osteoma of the wrist: Recent advances

Osteoid osteoma is a benign bone tumor usually arising in the diaphysis and metaphysis of the long bones, with male predominance (sex ratio, 2:1). Despite being the most common bone tumor in the wrist, it is still an atypical location for this lesion. The usual presentation is pain that is exacerbated at night and relieved by aspirin or non-steroidal anti-inflammatory drugs. This presentation is not always the case in the wrist, which leads to numerous differential diagnoses and often a delay in definitive diagnosis and treatment. Various imaging modalities can confirm the presence of the tumor and guide the surgical approach. Resection is the gold-standard, with radiofrequency gaining popularity in recent years.

Unusual Presentation of Osteoid Osteoma of the Cervical Spine with Dysphagia: A Case Report

It is uncommon for bony cervical spine lesions to cause dysphagia. Middle-aged female presented in the outpatient clinic with complaints of dysphagia of insidious onset. Patient's medical history, clinical manifestation and imaging studies guided the diagnosis of spinal osteoid osteoma. The presentation and surgical management are discussed in this report.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-03835-w.

Outcomes of Osteoid Osteoma Treated by Percutaneous CT-Guided Radiofrequency Ablation

Introduction Osteoid osteomas are the most frequent true benign bone tumor in the adolescent age group and the third most prevalent benign bone tumor overall. This study was designed to assess the effectiveness of the procedure and correlate it with the analgesia offered because of the significant burden of this illness and new literature supporting the successful outcomes of image-guided percutaneous radiofrequency ablation (RFA) in osteoid osteoma. Methodology  This hospital-based interventional trial was carried out in a tertiary care referral center. Forty-two patients with osteoid osteoma, ranging in age from 9 to 30, were included in the study. The patients received RFA guided by computed tomography (CT), and they were postoperatively monitored at one, two, and four weeks and three, six months, and 12 months. A numerical pain scale (NPS) was used to evaluate the patient's pain both before and after the procedure. The preoperative and postoperative results were contrasted. Results A total of 42 participants were enrolled in the study. Eight (19.05%) women and 34 (80.95%) men made up the group. Complete pain alleviation (NPS=0) was attained in 42.8% and 96.4% of the study group in the first and second weeks post-procedure. Almost all patients began protected weight-bearing at one week, according to their level of pain tolerance. Osteoid osteoma of the talus was a remnant lesion in one patient that required further treatment after two weeks. During the duration of the follow-up, no problems were recorded. Conclusion Percutaneous CT-guided RFA of osteoid osteoma is a safe, minimally invasive procedure and greatly reduces the duration of hospitalization. It has excellent functional outcomes and no known complications.

Benign Brain and Spinal Tumors Originating from Bone or Cartilage

Benign osseocartilaginous tumors of the spine are overall uncommon, representing between 1 and 13% of all primary bone tumors and less than 10% of all spinal tumors. Tumors in this category include osteoblastic lesions such as the related osteoid osteoma and osteoblastoma, and cartilage-forming lesions including osteochondroma, chondroma, and chondroblastoma. Aneurysmal bone cysts, giant cell tumors of bone, and eosinophilic granulomas also comprise benign tumors of the spine arising from bone. There is significant heterogeneity in the epidemiology, molecular biology, imaging features, and optimal treatment of these lesions. For example, osteoid osteoma is characterized by high expression of the cyclooxygenase enzymes, making it amenable to treatment with anti-inflammatory drugs initially, whereas other lesions such as osteoblastoma may require intralesional curettage or en bloc resection sooner. Generally, en bloc resection is preferred when possible to minimize risk of recurrence. Further, some tumors may arise in the setting of syndromic conditions, such as multiple chondromas arising in Ollier disease or Maffucci syndrome, or as part of genetic disorders, such as osteochondromas in the context of hereditary multiple exostosis. These lesions may present with local pain, cause neurological compromise or be discovered incidentally on routine imaging. The Enneking classification and Weinstein-Boriani-Biagini system are routinely used to classify lesions and assist in surgical planning. More novel techniques such as radiofrequency ablation and laser photocoagulation have been applied for the treatment of osteoid osteoma and may have utility in the treatment of other lesion types. A multidisciplinary approach is critical in the management of benign lesions of the spine, and both chemotherapeutic and surgical approaches are routinely used.

Spontaneous correction of scoliosis after curettage of spinal osteoid osteoma: How and when?

BACKGROUND

Scoliosis behavior after curettage of spinal osteoid osteoma has been not clarified as most studies regarding scoliosis secondary to osteoid osteoma (OO) were case reports. The aims of this study were to investigate (1) clinical and radiographic features of scoliosis secondary to OO; (2) scoliosis behavior after Curettage of OO.

METHODS

A retrospective study was performed at patients who were diagnosed as OO clinically or pathologically from July 1998 to December 2019 in a single institution. Age, gender, location of pain, location of lesion and curve pattern of scoliosis were collected preoperatively. Intraoperative blood loss, operation time and surgical complications were documented. VAS scores and curve magnitude were collected pre- and postoperatively and at last follow-up.

RESULTS

The mean operation time was 124 ± 32 min and the average intraoperative blood loss was 274 ± 134 ml. The mean preoperative VAS score was 6.2 ± 2.7, and the mean postoperative VAS score was 2.1 ± 1.8. Thoracic scoliosis was improved from 22.7 ± 10.6° to 6.2 ± 4.3° after operation, and to 4.1 ± 4.3° at last follow-up. Lumbar scoliosis was improved from 18.1 ± 7.4° to 6.7 ± 5.2° after operation, and to 5.3 ± 3.9° at last follow-up. Trunk shift was improved from 34.7 ± 12.4  to 10.5 ± 7.2 mm after operation, and to 8.4 ± 5.6 mm at last follow-up. There was no significant differences as to sagittal radiographic parameters (P > 0.05).

CONCLUSION

Patients with spinal OO had a significantly high incidence of scoliosis. Patients could get rapid relief of pain and scoliosis with low occurrence. Night pain, pain at the concave side of curve, normal sagittal alignment could help differentiate it from scoliosis associated with lumbar disc herniation.

Primary Osteosarcoma of the Breast: A Rare Case Report and Literature Review

Background

Primary osteosarcoma of the breast (POB) is an extremely aggressive and heterogeneous neoplasm that originates from nonepithelial elements of the mammary gland and accounts for fewer than 1% of breast cancers and fewer than 5% of all sarcomas.

Case Presentation

An 83-year-old Chinese woman went to our hospital because of a palpable mass she had had for 8 months in the left breast accompanied by persistent dull pain for 10 days. This mass was initially misdiagnosed as a degenerating fibroadenoma and was graded as probably benign (BI-RADS category 3) by ultrasonography (US) and computed tomography (CT) plain scan and contrast enhancement of chest. Eight months later, it was presumed to be highly malignant and graded as BI-RADS category 4C because of its rapid growth and more calcifications by US and CT. 99mTc-MDP whole-body bone imaging showed that there was a mass-like abnormal radioactive concentration of Tc-99m outside the bone of the left chest. The lumpectomy of the left breast was indicated, and the pathological findings were POB. She succumbed to respiratory failure caused by multiple lung metastases 4 months after the operation.

Conclusion

POB is rare, and US and CT cannot reliably distinguish the causes of calcified breast masses between benign and malignant tumors. It can be diagnosed by pathology when metaplastic carcinoma, malignant phyllodes tumor, or carcinosarcoma containing osteoid and bone is excluded. This case could help clinicians to improve the prognosis and treatment of this disease.

Benign Bone Tumors: An Overview of What We Know Today

Nonmalignant bone tumors represent a wide variety of different entities but maintain many common features. They usually affect young patients, and most can be diagnosed through imaging exams. Often asymptomatic, they can be discovered incidentally. Due to their similarities, these tumors may be challenging to diagnose and differentiate between each other, thus the need for a complete and clear description of their main characteristics. The aim of this review is to give a picture of the benign bone tumors that clinicians can encounter more frequently in their everyday work.

Needleless Ablation of Osteoid Osteoma and Osteoblastoma: The Emergent Role of MRgFUS

Osteoblastoma (OB) and osteoid osteoma (OO) are benign bone-forming tumors, with nearly identical basic microscopic features. The main difference is dimension (OO has usually a nidus measuring <2 cm in diameter). In addition, OB is biologically more active than OO, with a tendency to grow in size. Historically, treatments have included surgical resection and analgesics, although invasiveness and poor tolerance have led to the current standard of care moving toward interventional radiology, where radiofrequency ablation (RFA) represents the most diffuse technique. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) has recently emerged as another innovative alternative treatment, providing tumor ablation through a needleless and ionizing radiation-free modality. In addition, this technique has the ability to guarantee a very precise and controlled increase in temperature, delivering small amounts of energy that can accurately destroy only the lesion, avoiding healthy surrounding tissues. The present review focuses on MRgFUS as the less invasive, safe, effective, and durable treatment option for the management of osteoid osteoma and osteoblastoma, including a description of technical details, indications and outcomes.

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.

Management of Osteoblastoma and Giant Osteoid Osteoma with Percutaneous Thermoablation Techniques

Osteoblastoma (OB) is a rare, benign bone tumor, accounting for 1% of all primary bone tumors, which occurs usually in childhood and adolescence. OB is histologically and clinically similar to osteoid osteoma (OO), but it differs in size. It is biologically more aggressive and can infiltrate extraskeletal tissues. Therapy is required because of severe bone pain worsening at night. Moreover, non-steroid anti-inflammatory drugs (NSAIDs) are not a reasonable long-term treatment option in young patients. Surgical excision, considered the gold standard in the past, is no longer attractive today due to its invasiveness and the difficulty in performing a complete resection. The treatment of choice is currently represented by percutaneous thermoablation techniques. Among these, Radiofrequency ablation (RFA) is considered the gold standard treatment, even when the lesions are located in the spine. RFA is a widely available technique that has shown high efficacy and low complication rates in many studies. Other percutaneous thermoablation techniques have been used for the treatment of OB, including Cryoablation (CA) and laser-ablation (LA) with high success rates and low complications. Nevertheless, their role is limited, and further studies are necessary.

Osteoid osteoma of the femoral neck mistaken as a synovial herniation pit

A 36-year-old man presented with 1 year of atraumatic left lateral thigh, groin, and hip pain, and imaging consistent with the diagnosis of femoroacetabular impingement and a labral tear. Imaging concurrently demonstrated a synovial herniation pit. The patient underwent hip arthroscopy, which included femoroplasty, acetabuloplasty, labral debridement, and synovectomy. His pain persisted and further workup confirmed an osteoid osteoma that was mimicking a synovial herniation pit. The osteoid osteoma was treated with radiofrequency ablation. At 18 months follow-up, the patient reported complete resolution of his symptoms. We present the case to highlight distinguishing imaging and clinical findings of these similar-appearing lesions. While neither condition is particularly rare individually, the misidentification of osteoid osteoma as a synovial herniation pit is a unique feature of this case that lead to the patient's protracted clinical course.

An Unexpected Location of Enostosis, a Pediatric "Never Mind" Bone Lesion

Enostoses, also known as bone islands, are common benign sclerotic bone lesion that usually represent incidental findings. They constitute a small focus of compact bone within cancellous bone. Enostoses can be seen on radiographs, CT, and MRI, and are considered one of the skeletal do not touch lesions.

Aggressive osteoblastoma with a secondary aneurysmal bone cyst treated with denosumab

Osteoblastomas and aneurysmal bone cysts (ABC) are rare benign bone tumors that make up about 1%-2% of primary bone malignancies, typically occurring in young patients with a median age of 20 years, most commonly effecting the axial skeleton. ABCs may develop independently as primary lesions, or secondary to other bony lesions including osteoblastomas, chondroblastomas, and giant cell tumors. Treatment of unresectable or extensive osteoblastomas can be challenging. In 2013, the Food and Drug Administration (FDA) approved denosumab for the treatment of giant cell tumors of the bone due to its efficacy in these morbid bony lesions. Various case reports have shown that osteoblastomas can respond to denosumab. Furthermore, numerous ABC case reports have described the efficacy of denosumab in these situations. We herein describe a unique case of a young patient with an aggressive osteoblastoma and secondary ABCs who was successfully treated with denosumab.

Multimodality imaging of greater trochanter lesions

Purpose

Greater trochanter (GT) lesions are relatively uncommon. They can be traumatic, infective including tuber-culosis, inflammatory, and neoplastic (primary and metastatic osseous lesions). Although imaging of greater trochanter lesions remains essential for differential diagnoses, an image-guided biopsy is a mainstay for diagnosis and to guide subsequent management.

Material and methods

A retrospective search for the word ‘greater trochanter’ was performed of a computerised radiology information system (CRIS) of a tertiary referral centre for orthopaedic oncology over a period of 12 years (2007-2019). This revealed 6019 reports with 101 neoplasms. The imaging, histology, and demography were reviewed by a dedicated musculoskeletal radiologist.

Results

We identified 101 GT neoplasms with a mean age of 51.5 years (range 6 to 85 years) and a slight female predominance of 1.2 : 1 (46 males and 55 females). Using 30 years of age as a cut-off, we further segregated the patient cohort into 2 groups: 26 (25.74%) lesions in patients less than 30 years age and the remaining 75 (74.26%) lesions in patients over 30 years old. Chondroblastoma was the most common neoplasm in patients below 30 years of age, and metastases were the most common neoplasms in patients over 30 years of age.

Conclusions

Greater trochanter pathologies show a broad spectrum of aetiologies. Imaging including radiographs, computed tomography, magnetic resonance imaging, and nuclear medicine scans help to narrow down the differen-tials diagnosis.

Temperature Monitoring in Hyperthermia Treatments of Bone Tumors: State-of-the-Art and Future Challenges

Bone metastases and osteoid osteoma (OO) have a high incidence in patients facing primary lesions in many organs. Radiotherapy has long been the standard choice for these patients, performed as stand-alone or in conjunction with surgery. However, the needs of these patients have never been fully met, especially in the ones with low life expectancy, where treatments devoted to pain reduction are pivotal. New techniques as hyperthermia treatments (HTs) are emerging to reduce the associated pain of bone metastases and OO. Temperature monitoring during HTs may significantly improve the clinical outcomes since the amount of thermal injury depends on the tissue temperature and the exposure time. This is particularly relevant in bone tumors due to the adjacent vulnerable structures (e.g., spinal cord and nerve roots). In this Review, we focus on the potential of temperature monitoring on HT of bone cancer. Preclinical and clinical studies have been proposed and are underway to investigate the use of different thermometric techniques in this scenario. We review these studies, the principle of work of the thermometric techniques used in HTs, their strengths, weaknesses, and pitfalls, as well as the strategies and the potential of improving the HTs outcomes.

Osteoid osteoma of the rib with strong F-18 fluoro-deoxyglucose uptake mimicking osteoblastoma: a case report with literature review

Osteoid osteoma is a benign osteoblastic bone lesion, characterized by nocturnal pain alleviated by salicylates or nonsteroidal anti-inflammatory drugs. This tumor distinctly affects the long bones, typically the femur or tibia and is rarely located in the ribs. Usually, this tumor is usually diagnosed by computed tomography or magnetic resonance imaging, but F-18 fluoro-deoxyglucose positron emission tomographic (FDG-PET)/computed tomography is usually negative and is not used for diagnosis. We recently encountered a case of an osteoid osteoma located in the rib of 44-year-old Asian male with strong FDG uptake as high as 12.0 at the maximum standardized uptake value at FDG-PET/computed tomography. His computed tomography and magnetic resonance imaging showed osteosclerosis, bone marrow edema, and edema of surrounding tissues not only in the bone with nidus but also in the adjacent bone, and pathological findings showed strong infiltration munched radiology. Strong FDG uptake mimicking osteoblastoma. Osteoid osteoma with strong FDG uptake suggested a strong inflammatory response.

Musculoskeletal Interventional Radiology in the Pediatric Population: State of the Art

Interventional radiology procedures have been proven to be as effective as traditional surgery but usually are characterized by lower morbidity rates. In this article, the most diffuse IR treatments for pediatric lesions are reviewed with the aim of describing main advantages and drawbacks. Ablation procedures (in particular RFA and MRgFUS) are widely used for the management of osteoid osteoma and osteoblastoma whereas intracystic injection of methylprednisolone acetate is performed for simple bone cysts. Sclerosing agents and where possible, selective arterial embolization are used for treatment of aneurysmal bone cysts and other vascular malformations. In the management of malignant muscoloskeletal tumors, the role interventional radiology is mainly represented by percutaneous biopsies, and by adiuvant selective embolizations in presence of hypervascular lesions to be submitted to surgery.

Osteoid Tumors of Bone

We present a review of several bone (osteoid)-forming tumors including enostosis, osteoid osteoma, osteoblastoma, and osteosarcoma. These entities were chosen because they are reasonably common-neither seen every day nor rare. When applicable, recent information about the lesions is included.

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.

Computed tomography-guided percutaneous radiofrequency and laser ablation for the treatment of osteoid osteoma - long-term follow-up from 5 to 10 years

Purpose

The impact of computed tomography (CT)-guided, percutaneous radiofrequency ablation and interstitial laser ablation (ILA) on the management of patients with osteoid osteoma was studied. This was carried out by assessing immediate and long-term clinical outcomes, the complication rate, and repeat therapy effectiveness in recurrent patients who have already experienced percutaneous ablation.

Material and methods

Consecutive patients with osteoid osteoma were assessed before the interventional treatment in a single centre from 2010 to 2015. Patient demographics, complications, and recurrence were recorded. The pain was evaluated with Visual Analogue Scale (VAS). Percutaneous procedures were performed by means of radiofrequency thermoablation or ILA. Epidural or regional anaesthesia in the CT suite was applied in all procedures. Success, whether primary or secondary, was measured as complete pain relief without evidence of recurrence after the first or second procedure, respectively. Osteoid osteoma characteristics, procedure overview, and technical success were looked for in pre-procedural and procedural scans.

Results

Eighty-three per cent of osteoid osteomas were located in lower extremities, 56% of tumours were intracortical, and 83% of osteoid osteomas were extra-articular. The mean pre-procedure VAS score was 8.5 ± 0.8, while the overall primary success rate of radiofrequency thermoablation and ILA was 87.5%. No major complications were noted. The mean follow-up period for patients in was 7.5 years (5.0-10.2 years).

Conclusions

Percutaneous, CT-guided thermoablation proved to be effective and should become the method of choice in osteoid osteoma treatment because of its minimal invasiveness. Our results show that there is no risk of very late recurrence after achieving primary and secondary treatment success.

Percutaneous Ablative Therapies for the Management of Osteoid Osteomas: A Systematic Review and Meta-Analysis

PURPOSE

To evaluate safety and efficacy of percutaneous ablative therapy for the treatment for osteoid osteomas.

MATERIALS AND METHODS

PubMed database, Web of Science, and SCOPUS were searched from their inception until November 2019 for articles describing osteoid osteoma. Demographic data, success rates, pre- and post-procedure VAS scores, and complications were recorded. A random-effects meta-analyses of the VAS pain score at various time points were calculated.

RESULTS

For radiofrequency ablation, VAS scores for pain at pre-procedure, 24-48 h, and 3-6 months yielded cumulative pain scores of 7.64 +/- 0.175, 0.78 +/- 0.186, and 0.02 +/- 0.0196, respectively. For cryoablation, VAS scores at pre-procedure, 24-48 h, and 3-6 months yielded cumulative pain scores of 8.46 +/- 0.549, 0.975 +/- 0.66, and 0.112 +/- 0.08, respectively. For laser ablation, VAS scores at pre-procedure and 24-48 h yielded cumulative pain scores of 4.94 +/- 1.42, and 0.506 +/- 0.268, respectively. For microwave ablation, VAS scores at pre-procedure, 24-48 h, and 3-6 months yielded cumulative pain scores of 6.14 +/- 1.07, 1.636 +/- 1.215, and 0 +/- 0.0, respectively. All ablation methods resulted in significant immediate and lasting pain reduction (p < 0.001). Technical and clinical success rates and major complications for RFA, microwave ablation, laser ablation, and cryoablation did not differ significantly. Overall recurrence of bone pain at the same site occurred in 4.06% of all patients an average of 11 months post-procedure.

CONCLUSION

Percutaneous ablative therapies are safe and result in significant and lasting pain reduction as demonstrated through visual analog scale pain scores.

Limb Length Discrepancy and Angular Deformity due to Benign Bone Tumors and Tumor-like Lesions

Benign bone tumors and tumor-like lesions are frequently diagnosed in children and adolescents. The immature skeleton is at risk for growth disturbances and deformity because of the effects of the lesions on normal bone architecture and the physis. The development, manifestation, and severity of the limb length inequality and deformity differs between the various bone pathologies. Distraction osteogenesis, osteotomy, and guided growth are key tools in the treatment of limb inequality and deformity using a combination of external and internal fixation devices.

Osteoid Osteoma of the Scapular Neck: A Cause of Long-lasting Unexplained Pain

Introduction:

Osteoid osteoma (OO) is a common tumor of the diaphysis of long bone, where the reported incidence is up 10% of all benign bone tumors. Its presence in flat bone is seldom mentioned in literature and can be misleading when the bone involved is in proximity to a zone of wide variety of possible pathology. We report a case of a young patient with OO in a very rare location of the body –the scapular neck – that was misdiagnosed for a long period of time before receiving adequate therapy.

Case Report:

A 20-year-old female patient presented to the clinic with chronic left shoulder pain. During the past 2 years, she received medical and physical therapy, to deal with different diagnosis such as cervical spine pathology, muscular spasm, and rotator cuff disease. However, she did not improve. At time of presentation to our clinic, radiographs of the shoulder were done and turned to be inconclusively normal. After negative magnetic resonance imaging of the cervical spine, a computed tomography scan of the shoulder was done and showed a round well-defined lesion localized in the scapular neck with a focal lucent nidus within surrounding sclerotic reactive bone measuring 8.5 mm in largest diameter, compatible with OO. Bone scan showed increased uptake. The patient was given aspirin in an intention to test and treat. The patient had dramatic pain relieve at first, which confirmed the diagnosis of OO. But then, pain became unremitting, so a decision was made for radiofrequency ablation of the lesion which gave excellent results.

Conclusion:

OO is a common benign neoplasm with high variable clinical picture and anatomic localization. Despite being more common in long bone, flat bone OO localization should be always kept in mind. Careful history and physical examination should be done for each patient presenting with unexplained pain; night pain should always raise suspicion of this condition. Radiographs are not always conclusive, and the patient with high suspicion of this condition should undergo more investigation to make the diagnosis.

CT-guided radiofrequency ablation for osteoid osteomas: a systematic review

OBJECTIVES

CT-guided radiofrequency ablation (CT-RFA) is considered to be the gold standard for treatment of osteoid osteoma (OO) yet treatment failures (TFs) continue to be reported. This systematic review was conducted to evaluate factors associated with TF, such as ablation time, lesion location, and patient age as well as evaluating how TF has trended over time.

METHODS

Original studies reporting on patients undergoing CT-RFA of OO published between 2002 and 2019 were identified. TF was defined as patients with (1) recurrent or persistent pain +/- (2) imaging evidence of persistent OO. TFs were subdivided into those occurring after the index procedure (primary TF) or those occurring after repeat RFA (secondary TF). Subgroup analysis was performed for TF based on the study date (2002-2010 or 2010-2019), time duration of ablation at 90 °C (6 min or > 6 min), patient age, and tumor location (spinal vs. appendicular).

RESULTS

Sixty-nine studies were included for a total of 3023 patients. The global primary TF rate was 8.3% whereas the secondary TF rate was 3.1%. The TF rate reported in studies published after 2011(7%) was about half that during the earlier time period 2002-2010 (14%). There was no statistical difference in TF corrected for age, OO location, or duration of ablation (respectively p = 0.39, 0.13, and 0.23). The global complication rate was 3%, the most frequent being skin burns (n = 24; 0.7%).

CONCLUSIONS

A decrease in TF observed between 2011-2019 compared to 2002-2010 may reflect improvements in operator technique or advancements in equipment. Duration of ablation, patient age, or location of OO failed to significantly correlate with TF.

KEY POINTS

• CT-guided radiofrequency ablation of osteoid osteomas is a safe technique with a low rate of treatment failure (8.3% failure rate after the primary radiofrequency reducing to 3.1% following a secondary treatment). • The treatment failure rate has decreased over time, possibly due to an improved understanding of the disease process, better technique, and advances in equipment. • Duration of ablation, patient age, or lesion location did not significantly correlate with treatment failure.

MRI patterns indicate treatment success and tumor relapse following radiofrequency ablation of osteoblastoma

Purpose: To explore the typical magnetic resonance imaging (MRI) pattern of osteoblastoma (OB) after radiofrequency ablation (RFA) treatment and to identify signs indicating treatment success or relapse.Materials and methods: Forty-four follow-up MRI examinations of 15 patients with OB who had undergone 19 RFA procedures were analyzed retrospectively. An early follow-up group (1-4 months after RFA) and a late follow-up group (8-131 months after RFA) were established. The groups were further subdivided according to treatment success. Images were analyzed for the presence of central nidus enhancement (CNE), peripheral nidus enhancement (PNE), perifocal bone marrow edema (PBME) and fatty nidus conversion (FNC).Results: The early follow-up MRI image from every patient in the treatment success group exhibited a target-like appearance with negative CNE and positive PNE or PBME. PNE and PBME were observed in 93% and 71% of the early follow-up images, respectively. A target-like appearance was observed in 25% of the late follow-up images, and PNE and PBME were each observed in 20% of these images. FNC was not observed in the early follow-up images, but was seen in 55% of the late follow-up images. All three MRI images of the patients exhibiting clinical recurrence demonstrated strong CNE, PNE and extensive PMBE, which was in contrast to the images of the patients exhibiting treatment success.Conclusion: A target-like appearance of OB in early follow-up MRI examination indicates treatment success. PNE and PBME typically reduce over time and can lead to FNC in successfully treated patients. CNE recurrence, PNE and extensive PBME are signs of relapse.

Typical and Atypical Radiographic Features of Symptomatic Osteoblastoma in the Spine

BACKGROUND

Spine osteoblastomas (OBs) are relatively rare. In contrast to osteoid osteoma, radiologic and clinical manifestations of OB can be varied and atypical. Typical radiographic features in spinal OB include peritumoral bone sclerosis, bone marrow edema, and soft tissue edema. Atypical radiographic features include lesions involving ≥3 segments, lesions with extensive (≥3 segments) bone sclerosis, excessive edema (≥3 segments) of soft tissue and bone marrow, no intralesional calcification, and location in the vertebral body only. The aim of this study was to identify typical and atypical features of OB.

METHODS

Pretreatment computed tomography scans and magnetic resonance imaging were reviewed retrospectively. Percutaneous biopsies were performed to confirm pathology in atypical cases.

RESULTS

A total of 50 images from patients with diagnosed OB were reviewed. Atypical radiographic features were found in 18 cases (36%). Pathologic diagnosis was confirmed as OB in 86.2% (25/29) cases after percutaneous computed tomography-guided biopsy.

CONCLUSIONS

Our results show that >30% of spinal OB cases might have atypical radiographic features. In cases with atypical radiographic features, computed tomography-guided biopsies are recommended.

The one-in-all diagnostic value of 99mTc-MDP bone scan combining with single-photon emission tomography (SPECT)/CT imaging in spinal osteoblastoma

BACKGROUND

Osteoblastoma (OB) is an intermediate lesion, which makes the accurate preoperative diagnosis very important. ^99mTc-methylene diphosphonate (^99mTc-MDP) bone scan and SPECT/CT imaging were evaluated for their diagnostic value in spinal OB.

METHODS

This study was a retrospective analysis of patients with spinal OB lesions confirmed by pathology and diagnosed with bone scan and SPECT/CT for preoperative diagnosis from January 2008 to December 2018. The uptake levels of OB on planar bone scan were divided into low, medium, and high groups by visual assessment referring to the uptake of the normal rib, spine, and bladder. X-ray, CT, MRI, bone scan, and SPECT/CT imaging of the patients were analyzed for characteristics summary.

RESULTS

Twenty-five patients were diagnosed for spinal OB (17 males and 8 females with a proportion of 2.1:1), and the average age was 26.8 ± 10.8 years (range 5~59). There were 8 lesions located in the cervical, 6 in the thoracic, and 11 in the lumbar vertebrae. Twenty-four lesions involved posterior elements, especially the pedicles (14/25). Symptoms were predominantly painful with a duration of 18.3 ± 13.9 months (range 0.5~60 months). The lesion size ranged from 9 to 35 mm. All the lesions were low to high uptake in the planar bone scan, and the percentages of low to high levels were 1 (4%), 8 (32%), and 16 (64%) cases.

CONCLUSIONS

Spinal OB mainly involved the posterior area, and elderly patients should be considered as well. SPECT/CT combined the characteristics of bone uptake and anatomical features of bone tumors, proving its one-in-all diagnostic value for spinal OB and other osteogenic tumors.

Primary Osteosarcoma of the Breast

Editor's Note.-RadioGraphics continues to publish radiologic-pathologic case material selected from the "best case" presentations of the American Institute for Radiologic Pathology (AIRP), a program of the American College of Radiology. The AIRP conducts a 4-week Radiologic Pathology Correlation Course, which is offered five times per year. On the penultimate day of the course, the best case presentation is held at the American Film Institute Silver Theater and Cultural Center in Silver Spring, Md. The AIRP faculty identifies the best cases, from each organ system, brought by the resident attendees. One or more of the best cases from each of the five courses are then solicited for publication in RadioGraphics. These cases emphasize the importance of radiologic-pathologic correlation in the imaging evaluation and diagnosis of diseases encountered at the institute and its predecessor, the Armed Forces Institute of Pathology (AFIP).

Case study of radial fibrolamellar bone tissues in the outer cortex of basal sauropods

The histology of sauropod long bones often appears uniform and conservative along their evolutionary tree. One of the main aspects of their bone histology is to exhibit a fibrolamellar complex in the cortex of their long bones. Here, we report another bone tissue, the radial fibrolamellar bone (RFB), in the outer cortex of the humeri of a young adult cf. Isanosaurus (Early to Late Jurassic, Thailand) and an adult Spinophorosaurus nigerensis (Early to Middle Jurassic, Niger) that do not exhibit any pathological feature on the bone surface. Its location within the cortex is unexpected, because RFB is a rapidly deposited bone tissue that would rather be expected early in the ontogeny. A palaeopathological survey was conducted for these sampled specimens. Observed RFB occurrences are regarded as spiculated periosteal reactive bone, which is an aggressive form of periosteal reaction. A 'hair-on-end' pattern of neoplasmic origin (resembling a Ewing's sarcoma) is favoured for cf. Isanosaurus, while a sunburst pattern of viral or neoplasmic origin (resembling an avian osteopetrosis or haemangioma) is favoured for Spinophorosaurus. This study highlights the importance of bone histology in assessing the frequency and nature of palaeopathologies. This article is part of the theme issue 'Vertebrate palaeophysiology'.

Technical and nidus-specific factors associated with adequacy of intraprocedural biopsy samples preceding radiofrequency ablation of osteoid osteoma

PURPOSE

To examine the diagnostic yield of intraprocedural percutaneous biopsy performed at the time of radiofrequency ablation of suspected Osteoid Osteoma (OO) and identify technical and nidus-specific factors associated with diagnostic adequacy.

MATERIALS AND METHODS

Following IRB approval, a total of 42 patients (male: 28, female: 14; mean age: 29 years) who underwent intraprocedural biopsy immediately prior to RFA between June 2010 and June 2017 were retrospectively identified. The nidi were located in various locations. The nidi had a mean size of 6.3 mm (range: 3-11 mm, Standard deviation (SD): 2.26). Core biopsies were performed by one of 15 operators. Biopsies were performed with two needle types ranging from 11-G to 15-G with a mean number of samples of 1.8 (range: 1-5, SD: 1.01). Electronic records and imaging were reviewed for demographics, nidus characteristics, biopsy details and diagnostic yield. Multivariate logistic regression of nidus-specific and biopsy-specific factors was performed.

RESULTS

A total of 22/42 (52.3%) of the biopsies were adequate for histological diagnosis of OO. For the two experienced operators, the diagnostic yield was 67% (6/9) and 80% (8/10). Biopsy adequacy was significantly correlated with presence of an osteoid matrix (p = 0.03), obtaining >1 core sample (p = 0.03), the needle track passing through the nidus (p = 0.0003) and thinner (2.5 mm) intraprocedural CT slices (p = 0.03). On multivariate analysis, use of thinner intraprocedural CT slices was found to be associated with adequate biopsy (p = 0.02).

CONCLUSION

Intraprocedural percutaneous biopsy samples of nidi highly-suspected to be OO at the time of RFA were diagnostic in 52% of patients. Multivariate analysis shows thinner intraprocedural CT slices to be a significantly associated with biopsy adequacy.

Tumours of the talus - A pictorial review

BACKGROUND

Primary bone tumours of the talus are a rare entity and seldom described in the literature. Due to this, often the diagnosis and management of such cases are delayed. This study aims to describe a spectrum of lesions identified within our department and provide a pictorial review with the goal to aid radiologists in the evaluation and diagnosis of such lesions.

MATERIALS & METHODS

A retrospective study was conducted within our department, identifying all talar lesions, confirmed on histopathological and radiological diagnosis.

RESULTS

Results revealed 75 cases of talar lesions. Benign tumours formed the bulk of the lesions identified accounting for 85% of all cases. The most common benign tumour was chondroblastoma (n = 23). Malignant tumours were detected in 6 cases. Other lesions included osteomyelitis and avascular necrosis.

CONCLUSION

We present a variety of tumours and tumour-like conditions of the talus. Radiologists as well as orthopaedic surgeons need to be aware of such lesions, to prompt early diagnosis and initiate management in timely fashion.

What's new in bone forming tumours of the skeleton?

Bone tumours are difficult to diagnose and treat, as they are rare and over 60 different subtypes are recognised. The emergence of next-generation sequencing has partly elucidated the molecular mechanisms behind these tumours, including the group of bone forming tumours (osteoma, osteoid osteoma, osteoblastoma and osteosarcoma). Increased knowledge on the molecular mechanism could help to identify novel diagnostic markers and/or treatment options. Osteoid osteoma and osteoblastoma are bone forming tumours without malignant potential that have overlapping morphology. They were recently shown to carry FOS and-to a lesser extent-FOSB rearrangements suggesting that these tumours are closely related. The presence of these rearrangements could help discriminate these entities from other lesions with woven bone deposition. Osteosarcoma is a malignant bone forming tumour for which different histological subtypes are recognised. High-grade osteosarcoma is the prototype of a complex karyotype tumour, and extensive research exploring its molecular background has identified phenomena like chromothripsis and kataegis and some recurrent alterations. Due to lack of specificity, this has not led to a valuable novel diagnostic marker so far. Nevertheless, these studies have also pointed towards potential targetable drivers of which the therapeutic merit remains to be further explored.

3D imaging and stealth navigation instead of CT guidance for radiofrequency ablation of osteoid osteomas: a series of 52 patients

Background

Osteoid osteomas are benign bone neoplasms that may cause severe pain and limit function. They are commonly treated by radiofrequency ablation (RFA) through a needle inserted into the nidus of the lesion under CT guidance, which is associated with exposure of young patients to relatively high dose of radiation. The objective of this study was to investigate the amount of radiation, effectiveness and safety of an alternative imaging approach, the 3D image-guided (O-arm) technology and the Stealth navigation.

Methods

We retrospectively reviewed 52 electronic medical files of patients (mean age 24.7 years, range 8–59 years) who were treated with thermal ablation of benign osteoid osteomas guided by the navigated O-arm-assisted technique in our institution between 2015 and 2017. Data were extracted on the associated complications, the reduction in pain at 3 months and one year postoperatively, and the amount of radiation administered during the procedure.

Results

The level of pain on a visual analogue scale decreased from the preoperative average of 7.73 to 0 at the 3-month follow-up. The mean dose-length product was 544.7 mGycm² compared to the reported radiation exposure of 1971–7946 mGycm² of CT-guided radio ablations. The one intra-operative complication was a superficial burn in the subcutaneous lesion in a tibia that was treated locally with no major influence on recovery.

Conclusions

RFA ablation guided by 3D O-arm stealth navigation is as effective as the traditional CT-guided technique with the advantage of lower radiation exposure.

Trial registration

Retrospective study number 0388–17-TLV at Tel Aviv Sourasky Medical Center IRB, approved at 25.10.17.

Image-guided Percutaneous Radiofrequency Ablation for Osteoid Osteoma: Experience from a Developing Nation

Objective

The purpose of this study is to report our experience in using image-guided percutaneous radiofrequency ablation (RFA) for the treatment of osteoid osteoma (OO) and the subsequent duration of pain relief over a period of about six years (May 2013-March 2019; 70 months) at a tertiary-care hospital in a developing nation.

Methods

A retrospective study was performed at the radiology department of Aga Khan University, Karachi, Pakistan. All patients who had undergone image-guided percutaneous RFA for OO between May 2013-March 2019 were included. All cases had been performed with CT-guidance under general anesthesia, with an additional local anesthesia injection also administered to the patients. A soloist needle had been used for RFA. The primary success rates, complications, symptom-free intervals, and follow-ups were evaluated.

Results

In total, 15 patients (11 males, 4 females) of a mean age of 13.93 years (range: 5-25 years; median age: 14.5 years) with OO underwent image-guided percutaneous RFA during a period of 70 months. Eleven lesions were located in the femur, three in the tibia, and one in the humerus. The mean nidus size was 8.1 x 5.73 mm [range: (4.9-11.5) x (3.8-9.1) mm]. All patients were successfully treated and experienced resolution of pain in 2.36 months (range: 1-4 months). During the follow-up period (range: 3-40 months; mean: 13.85 months; median: nine months), none of the patients experienced any relapse or persistent symptoms. No major complications were reported.

Conclusion

Image-guided percutaneous RFA is a minimally invasive and safe treatment option with high efficiency and a high rate of technical success for the treatment of OO. The risk of recurrence is remote with all patients achieving independent recovery.

Safe and Effective Treatment Choice for Osteoid Osteoma: Computed Tomography-guided Percutaneous Radiofrequency Ablation

Introduction

Osteoid osteoma (OO) is a painful, benign, bone-forming tumor characterized by a small central nidus surrounded by sclerotic tissue. The aim of the present study was to evaluate the clinical outcome after computed tomography (CT)-guided radiofrequency ablation (RFA) in patients with OO performed from January 2012 to June 2018 and to confirm the safety and efficacy of CT-guided RFA.

Methods

Between January 2012 and June 2018, a total of 63 patients were treated with CT-guided RFA. Pre- and post-treatment pain, further treatment after the RFA procedure, observed complications, and satisfaction with the treatment were recorded for an assessment of clinical effects in all patients. The patients were evaluated with the visual analog scale (VAS) pre-procedure and at three months post-procedure.

Results

Of the patients, 39 were males and 24 were females with a mean age of 21 ± 9.7 (range, 9 to 41) years. The mean follow-up was 16 ± 2.1 (range, 12 to 19) months. The mean duration of the procedure was 34 ± 11.4 (range, 22 to 47) min. All of the patients were diagnosed with OO pathologically. A statistically significant difference was found between the pre-procedural and post-procedural VAS scores (p<0.001). Complications were observed in six patients including one peroneal nerve lesion, three minor skin burns, and two minor skin infections.

Conclusion

This study shows that CT-guided RFA is a safe and effective treatment for OO. It is thought that RFA could be the primary treatment choice for most OO with typical symptoms and radiological findings.