• High intensity focused ultrasound
• MR-HIFU
• MR-guided HIFU
• Osteoid osteoma
• Reactive sclerosis

• Humans
• Female
• Male
• Bone Neoplasms/diagnostic imaging
• Osteoma, Osteoid/diagnostic imaging
• Treatment Outcome
• Sclerosis/diagnostic imaging
• Adult
• Adolescent
• Young Adult
• Prospective Studies
• High-Intensity Focused Ultrasound Ablation/methods
• Child
• Quality of Life
• Magnetic Resonance Imaging, Interventional/methods
• Middle Aged

• Computed tomography
• Magnetic resonance imaging
• Osteoid osteoma
• Radiofrequency ablation
• Subchondroplasty

• Humans
• Positron Emission Tomography Computed Tomography/methods
• Fluorine Radioisotopes
• Fluorides
• Bone Neoplasms/diagnostic imaging
• Bone Neoplasms/secondary

• Bone scintigraphy
• CT
• Foot
• MRI
• Osteoid osteoma
• Radiofrequency ablation
• Small bones

• Humans
• Osteoma, Osteoid/diagnostic imaging
• Bone Neoplasms/diagnostic imaging
• Diagnosis, Differential
• Child
• Magnetic Resonance Imaging/methods
• Hip Joint/diagnostic imaging
• Tomography, X-Ray Computed/methods

• Humans
• Male
• Adolescent
• Osteoma, Osteoid/diagnostic imaging
• Magnetic Resonance Imaging/methods
• Diagnosis, Differential
• Bone Neoplasms/diagnostic imaging
• Hip Joint/diagnostic imaging
• Hip Joint/pathology

• bone tumor
• complications
• life quality
• osteoid osteoma
• pain
• percutaneous radiofrequency ablation
• thermal ablation

• CT
• MRI
• Osteoid osteoma
• Radiofrequency ablation

• cone-beam computed tomography
• ct-guided surgery
• curettage
• hybrid operating room
• osteoid osteoma

• Humans
• Male
• Female
• Adult
• Osteoma, Osteoid/diagnostic imaging
• Osteoma, Osteoid/surgery
• Osteoma, Osteoid/pathology
• Tomography, X-Ray Computed/methods
• Radiography, Interventional/methods
• Bone Neoplasms/diagnostic imaging
• Bone Neoplasms/surgery
• Cone-Beam Computed Tomography/methods
• Pain
• Talus/pathology
• Postoperative Complications
• Calcaneus/pathology
• Treatment Outcome

• Bone regeneration and reconstruction
• Bone substitutes
• Bone tumor
• Bone tumor treatment
• Local anti-cancer efficacy
• Residual tumor cells

• Humans
• Osteoma, Osteoid/diagnostic imaging
• Osteoma, Osteoid/surgery
• Prospective Studies
• Catheter Ablation/methods
• Radiofrequency Ablation
• Treatment Outcome
• Pain/surgery
• Anti-Inflammatory Agents, Non-Steroidal/therapeutic use
• Bone Neoplasms/diagnostic imaging
• Bone Neoplasms/surgery

• Osteoid osteoma
• management algorithm
• pediatric
• pediatric back pain
• spine

• Efficacy
• MRgFUS
• Meta-analysis
• Osteoid osteoma
• Safety
• Success rate

• Humans
• Osteoma, Osteoid/diagnostic imaging
• Osteoma, Osteoid/surgery
• Prospective Studies
• Pain
• Bone Neoplasms/diagnostic imaging
• Bone Neoplasms/surgery
• Magnetic Resonance Spectroscopy
• Treatment Outcome

• CT-guided radiofrequency ablation
• Interventional radiology
• Orthopedic surgery
• Osteoid osteoma
• Pediatric radiology

• atypical tumours
• benign neoplasms
• benign tumours
• difficult diagnosis
• disease masking
• intraoperative 3D navigation
• osteoid osteoma
• thermoablation
• treatment trends

• Aneurysmal bone cyst
• Benign spine tumors
• Eosinophilic granuloma
• Fibrous dysplasia
• Giant cell tumor of bone
• Osteoblastoma
• Osteochondroma
• Osteoid osteoma

• Humans
• Spinal Neoplasms/diagnostic imaging
• Spinal Neoplasms/surgery
• Osteoma, Osteoid/diagnostic imaging
• Osteoma, Osteoid/surgery
• Osteoblastoma/surgery
• Bone Neoplasms/diagnostic imaging
• Bone Neoplasms/genetics
• Bone Neoplasms/surgery
• Cartilage/pathology
• Osteochondroma/diagnostic imaging
• Osteochondroma/surgery
• Spinal Cord Neoplasms
• Brain/pathology

Proximal femoral osteoid osteoma (OO) is extremely easy to be misdiagnosed or missed. The purpose of this study was to retrospectively analyze the clinical data of patients with proximal femoral OO in order to determine the clinical manifestation and imaging characteristics of the disease, so as to provide help for the preoperative diagnosis and clinical treatment of proximal femoral OO.

This was a retrospective study involving 35 patients with proximal femoral OO admitted into our hospital from January 2015 to January 2021. The baseline characteristics of the participants included; 24 males and 11 females, aged between 13 and 25 (mean 16.2) years old, and the course of the disease was 1 to 14 (mean 6.3) months. We used previous medical experience records of the patients to analyze for the causes of misdiagnosis. Moreover, we compared the difference between preoperative and postoperative treatment practices in alleviating pain in OO patients and restoring hip function. Follow-ups were carried out regularly, and patients advised to avoid strenuous exercises for 3 months.

We followed up 35 patients (25 intercortical, 4 sub-periosteal, and 6 medullary) for an average of 41.4 months. We found that 15 patients (42.9%) had been misdiagnosed of synovitis, perthes disease, osteomyelitis, intra-articular infection, joint tuberculosis and hip impingement syndrome, whose average time from symptoms to diagnosis were 6.3 months. Postoperative pain score and joint function score improved significantly compared with preoperative, and complications were rare.

Open surgical resection constitutes an effective treatment for proximal femoral OO by accurately and completely removing the nidus. Wrong choice of examination, and the complexity and diversity of clinical manifestations constitutes the main reasons for the misdiagnosis of proximal femoral OO.

• The Natural Science Foundation of Hunan

Giant frontoethmoidal osteomas are rare, slow-growing, benign osseous tumours, frequently causing severe life impairing symptoms due to their proximity to noble structures. Initially, osteomas are often diagnosed on radiographs by chance. Their aetiology can be considered ambiguous. They may either be treated by active observation, medical therapy, radio and thermal therapy, or surgery.

We report the case of a 56-year-old female patient with a giant osteoma spreading from the nasal cavity to the entire frontoethmoidal sinus, leading to headaches, respiratory problems, and nausea for several years. For a period of 20 years, a watch and wait approach was applied. Finally, the osteoma was removed using a combined open and endoscopic approach. One year after the operation, a secondary mucocele developed, accompanying headaches and facial pressure due to its continuous expansion. Despite numerous consultations, she refused surgical intervention until today.

Early detection and removal of frontoethmoidal osteomas improves the prognosis for a favourable treatment outcome. The smaller the osteoma, the easier it can be removed endoscopically. The decision to perform surgery was made when the condition drastically affected the patient's quality of life. To date, there is still no strong consent regarding the best surgical approach and the best time to do it.

The combination of open and endoscopic surgery remains a safe and straightforward procedure for the removal of giant frontoethmoidal osteomas. Early detection and intervention are crucial for a predictable minimally invasive treatment with a favourable outcome for the patient.

•

Early removal of frontoethmoidal osteomas improves the prognosis for a favourable minimally invasive treatment outcome.

To analyze the causes of misdiagnosis and missed diagnosis in spinal osteoid osteoma, and to put forward solutions to improve diagnosis accuracy and treatment efficacy in patients.

We performed a retrospective cohort study on patients with spinal osteoid osteoma in Beijing Jishuitan Hospital from January 1983 to September 2019. All patients underwent surgery. The outcome measures were the extent of local pain, nocturnal pain, radicular symptoms of extremities after surgery, and reduction or disappearance of lesions on CT after surgery.

Thirty‐seven patients with spinal osteoid osteoma were recruited in the study. A total of 27% were female, and the mean (SD) age at diagnosis was 21.3 (8.7) years. A total of 87.0% of patients presented with nocturnal pain, and 94.7% of patients were responsive to NSAIDS treatment. The mean (SD) time from the initial onset of symptoms to the final diagnosis was 14.7 (12.5) months. Only four of 37 (10.8%) patients were correctly diagnosed with spinal osteoid osteoma on the first visit to the local hospital. CT is associated with a higher diagnosis rate than X‐ray or MRI on the first visit. Surgical navigation was used in 88.9% of patients who underwent curettage resection, and in 10% of patients who underwent en bloc resection. A total of 37 of 37 patients (100%) reported relief of local pain and radicular symptoms of extremities after surgery, and no recurrence of tumors was found during follow‐ups.

Spinal CTs are recommended to be performed if osteoid osteoma is suspected based on clinical manifestation, including nocturnal pain and responsiveness to NSAIDS treatment, to avoid misdiagnosis and missed diagnosis of spinal osteoid osteoma.

• Arthroscopy
• Benign neoplasms
• Elbow
• Intra-articular
• Osteoid osteoma
• Radiofrequency ablation
• Tumours

Osteoporosis is a result of an imbalance in bone remodeling. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have been considered as a potentially promising treatment for osteoporosis. However, the therapeutic effect, genetic alterations, and in vivo behavior of exogenous EVs for osteoporosis in mice models remain poorly understood.

A multiplexed molecular imaging strategy was constructed by micro-positron emission tomography (µPET)/computed tomography (CT), µCT, and optical imaging modality which reflected the osteoblastic activity, microstructure, and in vivo behavior of EVs, respectively. RNA sequencing was used to analyze the cargo of EVs, and the bone tissues of ovariectomized (OVX) mice post EV treatment.

The result of [¹⁸F]NaF µPET showed an increase in osteoblastic activity in the distal femur of EV-treated mice, and the bone structural parameters derived from µCT were also improved. In terms of in vivo behavior of exogenous EVs, fluorescent dye-labeled EVs could target the distal femur of mice, whereas the uptakes of bone tissues were not significantly different between OVX mice and healthy mice. RNA sequencing demonstrated upregulation of ECM-related genes, which might associate with the PI3K/AKT signaling pathway, in line with the results of microRNA analysis showing that mir-21, mir-29, mir-221, and let-7a were enriched in Wharton’s jelly-MSC-EVs and correlated to the BMP and PI3K/AKT signaling pathways.

The therapeutic effect of exogenous WJ-MSC-EVs in the treatment of osteoporosis was successfully assessed by a multiplexed molecular imaging strategy. The RNA sequencing demonstrated the possible molecular targets in the regulation of bone remodeling. The results highlight the novelty of diagnostic and therapeutic strategies of EV-based treatment for osteoporosis.

• RNA sequencing
• Wharton’s jelly mesenchymal stem cells
• [18F]NaF
• extracellular vesicles
• osteoporosis

Osteoid osteomas of the foot are rare, with a varying and atypical clinical as well as radiological presentation impeding early diagnosis and treatment. The aim of the present multicentre study was to 1) analyze epidemiological, clinical and radiological findings of patients with foot osteoid osteomas and to 2) deduce a diagnostic algorithm based on the findings.

A total of 37 patients (25 males, 67.6%, mean age 23.9 years, range 8–57 years) with osteoid osteomas of the foot were retrospectively included, treated between 2000 and 2014 at 6 participating tertiary tumor centres. Radiographic images were analyzed, as were patients’ minor and major complaints, pain relief and recurrence.

Most osteoid osteomas were located in the midfoot (n = 16) and hindfoot (n = 14). Painful lesions were present in all but one patient (97.3%). Symptom duration was similar for hindfoot and midfoot/forefoot (p = 0.331). Cortical lesions required fewer x‑rays for diagnosis than lesions at other sites (p = 0.026). A typical nidus could be detected in only 23/37 of x‑rays (62.2%), compared to 25/29 CT scans (86.2%) and 11/22 MRIs (50%). Aspirin test was positive in 18/20 patients (90%), 31 patients (83.8%) underwent open surgery. Pain relief was achieved in 34/36 patients (outcome unknown in one), whilst pain persisted in two patients with later confirmed recurrence.

As previously reported, CT scans seem to be superior to MRIs towards detection of the typical nidus in foot osteoid osteomas. In patients with unclear pain of the foot and inconclusive x‑rays, osteoid osteoma should be considered as differential diagnosis.

• Diagnosis
• Foot tumour
• Osteoid osteoma
• Radiology
• Symptoms

Intra-articular osteoid osteoma (iaOO) can be found in 5.2% up to 10% of cases. They may cause non-specific symptoms, mimicking degenerative or traumatic pathologies. If iaOO is left untreated, it may lead to severe muscle atrophy, tenderness, swelling, and limited range of motion. Therefore, surgical treatment is recommended. The main goal of surgical treatment is complete removal or destruction of iaOO.

To evaluate the efficiency of arthroscopic removal of iaOO of the knee in our cases and cases available in the literature.

Analysis of available hospital records of four patients with iaOO of the knee treated by arthroscopic removal from August 2005 to December 2015 at our Department was performed. All patients had a diagnosis of iaOO confirmed by histopathologic analysis. Additional literature review of cases of iaOO of the knee available on PubMed and Google Scholar was made. All cases of iaOO of the knee treated by arthroscopic or arthroscopically assisted removal were reviewed in order to further evaluate the efficiency of the method.

The average age of patients included in our study was 23.2 (range 16-37) years. The average duration of the symptoms prior to surgery was 14.2 (range 6-24) months. All of the patients had persistent knee pain. Three patients reported worsening of pain during the night, while two reported worsening of pain during activity. Three patients reported alleviation of pain on non-steroidal anti-inflammatory drugs (NSAIDs), while one patient reported partial alleviation of pain on NSAIDs. No intraoperative complications were noted, and the postoperative period was uneventful in all patients. The patients reported immediate pain relief in the postoperative period. No recurrence of the disease was noted in any of the patients during the follow-up period of at least 24 mo. The literature review revealed 14 cases with an average age of 27.6 (range 16-48) years and onset of symptoms 27.7 (range 6-108) months prior to surgery, with recurrence of the disease noted in a single case.

Arthroscopic removal is an efficient treatment method that allows excision of iaOO that is neither insufficient nor excessive, thus avoiding disease recurrence while obtaining adequate material for histopathologic analysis.

• Osteoid osteoma
• Knee
• Arthroscopy
• Bone diseases
• Surgical procedures
• Operative
• Pathology
• Surgical

• en-bloc resection
• imaging
• medical therapy
• percutaneous ablation
• review
• Οsteoid osteoma

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.

• FDG
• Osteoid osteoma
• computed tomography
• magnetic resonance imaging
• osteosclerosis
• positron emission tomographic

To assess efficacy and safety of imaging-guided radiofrequency ablation (RFA) of Osteoid Osteoma (OO) in both typical and atypical sites.

Between January 2014 and March 2019, 102 consecutive percutaneous RFA were performed and retrospectively reviewed. The procedures were performed using a RFA bipolar ablation system (Covidien, exposed tip of 0.7-1cm), under Computed Tomography (CT) guidance or using a navigation system (Masmec) under CT and Cone Beam CT (CBCT) guidance. Patients were followed up over 24 months. Clinical success and recurrences were considered on the base of established criteria. In patients with clinical failure and/or imaging evidence of relapse, retreatment was considered.

Administered power per-procedure was ≤8 W (mean temperature, 90°C). The pre-procedure average value of visual analog scale (VAS) was 8.33+/-0.91. Primary and secondary success rate 96.08% (98/102) and100% (102/102), respectively. No major complication was described. Technical success was proved in every patient by CT scan acquisition after needle positioning. Relapse and tumour location were significantly correlated (p-value = 0.0165). The mean dose-length product was 751.55 mGycm2. Advanced bone healing was noted in 68 lesions after 1y-follow up and in 86 lesions after 2y-follow up.

Imaging-guided percutaneous RFA is a highly effective technique for OO, both in typical and atypical sites. CT or CBCT guidance, navigation systems and operator experience grant the technical success, which is the most crucial parameter affecting outcome.

• Adolescent
• Adult
• Bone Neoplasms/complications
• Bone Neoplasms/diagnosis
• Bone Neoplasms/therapy
• Cancer Pain/diagnosis
• Cancer Pain/etiology
• Cancer Pain/therapy
• Cone-Beam Computed Tomography
• Female
• Follow-Up Studies
• Humans
• Male
• Middle Aged
• Neoplasm Recurrence, Local/epidemiology
• Neoplasm Recurrence, Local/prevention & control
• Osteoma, Osteoid/complications
• Osteoma, Osteoid/diagnosis
• Osteoma, Osteoid/therapy
• Pain Measurement/statistics & numerical data
• Radiofrequency Ablation/methods
• Radiofrequency Ablation/statistics & numerical data
• Retrospective Studies
• Treatment Outcome
• Young Adult

Osteoid osteoma is a painful, benign and common bone tumor that is prevalent in young adults. The typical clinical presentation consists of pain that becomes worse at night and is relieved by nonsteroidal anti-inflammatory drugs. The most common imaging finding is a lytic lesion, known as a nidus, with variable intralesional mineralization, accompanied by bone sclerosis, cortical thickening and surrounding bone marrow edema, as well as marked enhancement with intravenous contrast injection. When the lesion is located in typical locations (intracortical bone and the diaphyses of long bones), both characteristic clinical and radiological features are diagnostic. However, osteoid osteoma is a multifaceted pathology that can have unusual presentations, such as intraarticular osteoid osteoma, epiphyseal location, lesions at the extremities and multicentric nidi, and frequently present atypical clinical and radiological manifestations. In addition, many conditions may mimic osteoid osteoma and vice versa, leading to misdiagnosis. Therefore, it is essential to understand these musculoskeletal diseases and their imaging findings to increase diagnostic accuracy, enable early treatment and prevent poor prognosis.

• Bone neoplasms
• Diagnosis
• Differential
• Magnetic resonance imaging
• Osteoid
• Osteoma
• Tomography
• X-ray computed

• Ankylosing spondylitis
• Arthroplasty
• Fracture
• Infection
• Osteoarthritis
• Osteoporosis
• Osteosarcoma
• Temporomandibular disorder

• Aged, 80 and over
• Diagnosis, Differential
• Female
• Humans
• Hyperostosis Frontalis Interna/diagnostic imaging
• Osteitis Deformans/diagnostic imaging
• Positron Emission Tomography Computed Tomography
• Skull/diagnostic imaging

• CT
• MRI
• PET
• computed analysis
• oncology

• Atypical presentations
• Differential diagnosis
• Hip
• Imaging
• Osteoid osteoma
• Recurrence