Aneurysmal Bone Cyst of the Third Metatarsal Treated Using Free Nonvascular Fibular Strut Graft-A Rare Case Report.

Introduction: An aneurysmal bone cyst (ABC) is an unusual, non-cancerous bone lesion that is characterized by its lytic (causing bone loss), hemorrhagic, and expanding nature. ABCs are relatively rare, making up only 1% of all bone tumors. These cysts are typically found in long bones and the spine but are very rarely seen in the metatarsal bones, making such occurrences quite uncommon. Case Report: In this case report, we present a case of ABC of the 3rd metatarsal in a 26-year-old female with complaints of long-standing foot pain and gradually increasing swelling of the dorsum of the foot. After radiological evaluation, she had undergone histopathological evaluation. An en bloc resection of the metatarsal along with the tumor mass was performed and the gap was replaced with an ipsilateral fibular strut graft. Histopathological examination of the resected tissue was suggestive of ABC without any evidence of malignancy. At the end of 1 year of follow-up, she is now completely pain free with intact rom of foot and ankle. Conclusion: The present study aims to describe a case of ABC of the metatarsal, a condition that not only poses a diagnostic dilemma but also constitutes a challenge in the management of lesion.

Minimizing neurovascular complications during image-guided percutaneous cryoablation of a cervical spinal aneurysmal bone cyst using protective doxycycline sclerotherapy: a case report.

Background: Aneurysmal bone cysts (ABC) are rare, locally aggressive bone tumors primarily observed in pediatric patients. Surgical curettage is the treatment of choice. Image-guided percutaneous cryoablation (CYOA) is a recently implemented alternative technique in cases not amenable to surgery. CYOA may be limited if the lesion is close to critical neurovascular structures. In this case report, a cervical spinal ABC was successfully treated using CYOA in combination with complementary and protective image-guided percutaneous doxycycline sclerotherapy (DS) to dissect and treat the portion of the lesion in contact with critical structures. Case Description: A 4-year-old male presented with a symptomatic ABC within the C5 vertebral body, which encompassed the right vertebral artery and contacted the right C5-C6 spinal cord and nerve roots. After ruling out surgery due to the proximity of critical neurovascular structures, treatment with CYOA was performed. However, subsequent follow-up showed recurrence in the part of the lesion contacting critical structures. A second approach was then decided, using DS to dissect and treat the most vulnerable portion and CYOA to treat the remaining tumor. Follow-up showed almost complete sclerosis of the lesion and total resolution of symptoms 3 years after treatment. Conclusions: Using DS to dissect and treat the portion of the lesion in contact with critical neurovascular structures during CYOA treatment of a cervical spinal ABC allowed for a safe and effective approach in our case.

Isolated calvarial aneurysmal bone cyst in a pediatric patient: illustrative case.

BACKGROUND: Aneurysmal bone cysts (ABCs) are benign, osteolytic lesions that can occur in long bones, vertebrae, or rarely, the skull. Here the authors present the case of a 15-year-old male with a primary ABC of the left frontoparietal skull along with a review of the literature to provide insight into the nature of this rare disease. OBSERVATIONS: An otherwise healthy 15-year-old male presented with a tense, painful lesion of the left frontoparietal scalp. He could not identify any inciting trauma, but first noted the lesion less than 2 weeks prior to presentation with progressive enlargement. Cranial imaging revealed a lytic skull lesion with fluid-fluid levels suggestive of ABC. Curative therapy was provided via wide excision of the lesion and calvarial reconstruction of the resultant skull defect. This was performed without complication, and histopathological evaluation confirmed the diagnosis of primary ABC. LESSONS: ABCs of the skull are rare entities and most often arise in the skull base versus the calvaria. Typically, these lesions are associated with an underlying bone pathology (secondary ABCs) but can be rarely seen as isolated lesions (primary ABCs). Clinical management consists of excision and adjuvant therapy for underlying pathology where appropriate.

Management of aggressive recurrent thoracic spine aneurysmal bone cyst in a 7-year-old male: A case report and review of the literature.

Background: Spinal aneurysmal bone cysts (ABCs) are rare, histologically benign tumors with aggressive behavior, which may cause bone and soft-tissue destruction, particularly affecting neural elements. Management of these tumors, including treatment modalities and follow-up protocols, remains challenging. Case Description: A 7-year-old boy presented with chest wall pain persisting for two months before admission, accompanied by progressive mono paresis lasting ten days before admission. Myelopathy signs were evident during the examination. Imaging confirmed a multicystic lesion at the T6 level involving the posterior elements of the vertebra, with significant cord compression. Due to deteriorating neurological function, he underwent urgent laminectomy and neural decompression, followed by subtotal tumor resection. Postoperative histopathological examination confirmed the diagnosis of an ABC, and the patient experienced significant neurological recovery. However, after 21 days, the patient was readmitted to the emergency department with severe paraparesis. Magnetic resonance imaging revealed rapid growth of the residual tumor, leading to cord compression. He underwent aggressive total tumor resection, T6 vertebral body corpectomy, and fixation with pedicle screws and cage insertion. Following the second surgery, prompt neurological recovery occurred. Conclusion: This rare case report emphasizes the importance of a close follow-up protocol for spinal ABCs in the pediatric population. It highlights the challenges in managing these tumors and the need for vigilant monitoring to detect and address rapid recurrences.

Tumors of the Posterior Elements of the Spine in Children-an Overview.

In this narrative review, we aim to describe the clinical features, diagnosis, and management of common primary osseous tumors affecting the posterior elements of the spine in children. We searched PubMed, Mendeley, and Google Scholar using the terms primary osseous tumors of the spine in children, tumors of the posterior elements of the spine, and names of individual tumors. The clinical features, investigations, and treatment modalities were analyzed, and a narrative review of the topic was prepared. We have included 54 studies published in the last 20 years. The majority are isolated reports or case series. Tumors of the posterior elements of the spine are rare. They are common in children and the majority of them are benign. Pain and deformity are common presentations. It is better to perform thorough investigations of children complaining of back pain to rule out primary tumors of the posterior elements of the spine.

Using Denosumab as a Nonsurgical Management of Aneurysmal Bone Cysts in the Pelvis.

Background: Aneurysmal bone cysts (ABCs) are infrequent, benign, and locally destructive lesions that most commonly occur during the first two decades of life. They usually affect the metaphysis of the long bones, but the pelvis is involved in 8%-12% of the cases. The management of pelvic ABCs is a challenging issue due to difficulties in choosing the appropriate approach, adjacent neurovascular bundles, the risk of intraoperative bleeding with difficulty achieving good hemostasis, and the risk of injury to the hip or sacroiliac joints. Limited data exist concerning the use of denosumab as a non-surgical treatment for pelvic ABCs. Our hypothesis was that denosumab might be an effective and safe solo treatment of cases with ABCs in the pelvis. Methods: We retrospectively assessed 20 patients with ABCs in the pelvis, who were treated by denosumab as a solo agent without surgery. Patients were assessed regarding disease control, the incidence of recurrence and non-oncological complications, and functional outcome. Results: The mean follow-up period was 38.5 months. Disease control was achieved in 16 patients (80%), with no local recurrence. Tolerable drug-related complications occurred in 15% of cases. The mean Musculoskeletal Tumor Society score was 92.3%. Conclusions: Denosumab may provide a reliable option in the nonsurgical treatment of ABCs of pelvic origin with expected lower morbidity than the surgical solution and tolerable complications. Further studies on the safety profile and long-term effects of denosumab especially in skeletally immature patients are required.

Gigantic aneurysmal bone cyst of the scapula in children treated with left total scapulectomy and humeral suspension: A case report.

INTRODUCTION AND IMPORTANCE: Aneurysmal bone cyst (ABC) is a benign, rapidly growing, osteolytic and could have hemorrhagic lesion. This cyst mostly occurs in females under 20 years old and is located predominantly in the metaphysis of long bones, followed by the pelvis and spine. ABC of the scapula is a rare case, and their treatment still remains controversial. CASE PRESENTATION: A 7-year-old girl has had a growing lump on her left shoulder since two years ago. Physical examination revealed local tenderness and a firm and immobile mass, which limit shoulder motion. The radiological and histopathological results confirmed the diagnosis of ABC of the scapula. The patient underwent a left total scapulectomy and humeral suspension reconstruction and was augmented with surgical mesh. There were no signs of postoperative infection or recurrence during the 1-year follow-up. The MSTS score was 24. CLINICAL DISCUSSION: There are many options for ABC treatment. Resection of the cyst is the treatment of choice for aggressive tumors (Enneking stage 3) or lesions in less essential bones. In scapula, the ABC treatment with total scapulectomy followed by humeral suspension is an effective method to decrease complications and reduce the risk of recurrence with a good clinical outcome. CONCLUSION: ABC of the scapula is a rare case. Tumor resection for aggressive ABC should be considered to decrease the recurrence rate. Total scapulectomy with humeral suspension is an effective method for treating ABC scapula (Enneking stage 3).

[Pediatric neurosurgical treatment of aneurysmal bone cyst at the level of thoracic spine]. / Aneurysmás csontcysta gyermek-idegsebészeti megoldása a háti gerinc magasságában.

Aneurysmal bone cysts are benign but locally aggressive bone tumours, most often affecting children and young adults. In this case report, we present the clinical  picture of a 15-year-old boy with progressive, chronic back pain. An MRI of thoracic spine  confirmed a T2 cystic spinal tumour. After considering potential options surgical removal was our choice and gross total removal was achieved with T1-3 short-segment fixation. Aneurysmal bone cysts are often rapidly expanding lesions with vascular  transformation. In order to avoid irreversible damage, in addition to early diagnosis, it is necessary to carefully consider the therapeutic options, perform surgical removal and stabilization as necessary. In case of the presented patient, extensive surgical removal and short-segmentation were performed. At 18 months of follow-up, he had no complaints and was asymptomatic. Follow-up imaging studies showed no residual or recurrent tumour to date.

Imaging of Fibro-osseous Lesions and Other Bone Conditions of the Jaws.

This review directs the focus on the imaging features of various fibro-osseous lesions and other bone lesions that can be of similar presentation. Broad diagnosis of "fibrous osseous lesion" may culminate in improper treatment and management. Radiographic discriminating factors between these entities are highlighted and summarized to improve the diagnostic process when encountering these lesions.

Fibrous dysplasia with aneurysmal bone cyst-like change occurring in pediatric orbit: case report and literature review.

PURPOSE: We report a case of fibrous dysplasia (FD) with aneurysmal bone cyst (ABC)-like change in a child with orbital involvement, review the related cases, and discuss clinical features, therapy, and prognosis of this disease. CASE PRESENTATION: A 10-year-old girl had right proptosis (degree of exophthalmos: OD 16 mm, OS 13 mm) and limited vision (visual acuity: OD 1.0, OS 0.8) without trauma. Preoperative CT showed a 5.0*4.3 cm right-sided crania-orbital communicating tumor. MRI indicated a well-defined multicystic mass with scattered fluid levels and soap bubble-like alterations. The child underwent total tumor resection and orbital parietal titanium mesh reconstruction. At 20 months of follow-up, the child has recovered from ocular problems, and the tumor has not recurred. CONCLUSION: FD combined with ABC rarely occurs in orbit and generally begins with ocular symptoms. The etiology is uncertain. Early diagnosis and surgery are essential. Complete resection is suggested whenever possible because residual lesions may recur.

A rare case of aneurysmal bone cyst of the anterior clinoid process in an 18-year-old female mimicking optic neuritis.

BACKGROUND: Aneurysmal bone cyst (ABC) is an uncommon, benign, vascular multicystic bony lesion that most frequently develops in the first two decades of life. The metaphysis of long bones, pelvic, and vertebral column are the most common locations. The precise underlying pathophysiology of ABCs formation remains unclear; however, it is believed that reactive processes subsequent to trauma or vascular disturbance may play an important role. Involvement of the skull base rarely occurs with a prevalence of up to 5% of intracranial ABCs. CASE PRESENTATIONS: An 18-year-old adolescent female with a history of progressive blurred vision since three months ago presented to our office. The brain and orbital MRI demonstrated no abnormal findings. After three months of glucocorticoid treatment with the diagnosis of multiple sclerosis, the visual impairment of the left eye deteriorated abruptly. The patient underwent an MRI and the imaging study demonstrated a well-defined 30 × 22 × 20-mm lesion at the anterior clinoid process with an extension to the optic canal and ethmoid sinus. The patient underwent pterional craniotomy, and the tumor was resected. The histopathological examination was suggestive of ABC. CONCLUSION: ABC and other conditions should be considered in young-age people with an early unilateral decline in vision and imaging studies should be obtained in early stages and during follow-ups.

Surgical management of pediatric spinal aneurysmal bone cysts: patient series.

BACKGROUND: Aneurysmal bone cysts (ABCs) are rare, highly vascular osteolytic bone lesions that predominantly affect pediatric populations. This report evaluates the clinicopathological data of pediatric patients with spinal ABCs. The medical records for all patients at Children's Hospital Los Angeles with biopsy-proven ABCs of the spine between 1998 and 2018 were evaluated. OBSERVATIONS: Seventeen patients, 6 males and 11 females, were identified. The mean age at surgery was 10.4 years (range, 3.5-20 years). The most common presenting complaint was pain at the lesion site 16/17 (94%), followed by lower-extremity weakness 8/17 (47%). Resection and intralesional curettage were performed in all patients. Three (18%) of 17 patients underwent selective arterial embolization prior to resection. Spinal stability was compromised in 15 of 17 patients (88%), requiring instrumented fusion. Five (29%) of the 17 patients received additional therapy including radiation, calcitonin-methylprednisolone, or phenol. Four (23.5%) of 17 patients experienced a recurrence, and the mean time to recurrence was 15 months. The postoperative follow-up ranged from 6 to 108 months (median, 28 months). Reoperation occurred after an average of 35 months. At the recent follow-up, patients were free of disease. LESSONS: Gross-total resection by intralesional curettage with case-dependent instrumented spinal fusion for instability remains an effective strategy for managing pediatric spinal ABCs. Long-term follow-up is necessary to detect tumor recurrence.

Aneurysmal bone cysts: A UK wide tumor center experience.

BACKGROUND AND OBJECTIVES: This multicenter retrospective series of consecutive extra-spinal aneurysmal bone cysts aims to identify risk factors for treatment failure. METHODS: Aneurysmal bone cysts treated within seven collaborating centers with over 12-months follow-up were eligible for inclusion. Survival analyses were performed to identify variables associated with recurrence using log-rank tests and Cox proportional hazard regression. RESULTS: One hundred and fifteen (M:F 60:55) patients were included. Median age at presentation was 13 years and median follow-up was 27 months. Seventy-five patients underwent surgical curettage and 27% of these required further intervention for recurrence. Of the 30 patients who underwent biopsy with limited percutaneous curettage as initial procedure, 47% required no further treatment. Patients under 13 years (log-rank p = 0.006, HR 2.3, p = 0.011) and those treated who had limited curettage (log-rank p = 0.001, HR 2.7, p = 0.002) had a higher risk of recurrence/persistence. CONCLUSIONS: There is a high risk of recurrence following surgical treatment for aneurysmal bone cysts and this risk is higher in young patients. However, the cyst heals in a substantial number of patients who have a limited curettage at the time of biopsy.

Unusual presentation of aneurysmal bone cyst (ABC) in children: pediatric intracranial osteosarcoma with secondary ABC.

A 13-year-old female patient presented with painless vision loss and proptosis for 18 months. Imaging findings were highly suggestive of a supraorbital aneurysmal bone cyst (ABC) for which she underwent complete surgical excision. Postoperatively, she developed left hemiparesis. Computed tomography angiography (CTA) revealed right complete internal carotid arterial (ICA) thrombosis. This was managed conservatively, and she improved in hemiparesis over the next 3 weeks. Histopathology report revealed osteosarcoma with secondary ABC, for which she was referred for radiotherapy. At 1.5 months follow-up, the patient's left lower limb power improved to 4 + /5. She was walking without support, and her left upper limb power was 4/5.

Adjunct role of liquid absolute alcohol intralesional sclerotherapy during the surgical management of spinal primary aneurysmal bone cyst in a child: a technical case report.

BACKGROUND: Aneurysmal bone cyst is composed of variable -sized cystic blood-filled spaces separated by connective tissue septae. First-line surgical resection of spinal aneurysmal bone cyst in a child with limited total blood volume can lead to massive intraoperative bleeding, thus limiting extent of resection. Our Centre's has good experience of using absolute alcohol as an effective immediate devascularizing agent during vertebral hemangioma surgery in children. MATERIAL AND METHODS: We report the first case of pediatric lumbar primary aneurysmal bone cyst in which completely blood-less piecemeal total resection of the lesion was performed after intraoperative absolute alcohol intralesional sclerotherapy. RESULTS: Completely blood-less piecemeal total resection of the lumbar aneurysmal bone cyst was performed after intraoperative absolute alcohol intralesional sclerotherapy. CONCLUSION: Intraoperative absolute alcohol intralesional sclerotherapy is a very effective devascularizing adjunct for complete piecemeal resection of spinal aneurysmal bone cyst in children with limited blood volume.

Management of RANKL-mediated disorders with denosumab in children and adolescents: a global expert guidance document.

CONTEXT: Denosumab is an effective treatment for many receptor activator of nuclear factor kappa-B ligand (RANKL)-mediated disorders but there are potential safety considerations and limited data to guide its use in children and adolescents. OBJECTIVE: This document seeks to summarise the evidence and provide expert opinion on safe and appropriate use of denosumab in paediatric RANKL-mediated disorders. PARTICIPANTS: Ten experts in paediatric bone and mineral medicine from six countries with experience in the use of denosumab participated in the creation of this document. EVIDENCE: Data was sourced from the published literature, primarily consisting of case reports/series and review articles due to the lack of higher-level evidence. Expert opinion of the authors was used substantially, where no published data was available. CONCLUSIONS: Denosumab is an effective treatment for RANKL-mediated disorders in children and adolescents but is often not curative and in some cases is best used in conjunction with surgical or other medical treatments. Careful multidisciplinary planning is required to define the goals of treatment and expert oversight needed to manage the risk of mineral abnormalities. Substantive, collaborative research efforts are needed to determine optimal treatment regimens and minimise risks.

Current indications for denosumab in benign bone tumours.

Denosumab is a fully humanised monoclonal antibody to RANK ligand, inhibiting the RANK-RANKL pathway. It promotes the apoptosis of osteoclast-like giant cells, a secondary ossification and connective tissue formation. Given its high efficacy, denosumab is the standard treatment of unresectable or metastatic giant cell tumour of bone (GCTB) requiring morbid surgery. Neoadjuvant administration of denosumab may be justified to enable the resection of the tumour in certain cases; it should be considered, however, with caution for joint-saving surgery due to high local recurrence rates. In cases of unresectable or metastatic GCTB, however, denosumab treatment should be administered for years or even as a lifelong therapy. This poses many yet unanswered questions concerning the frequency of denosumab treatment as well as the ratio of the adverse events in the following years. Denosumab suppresses, not directly targets, the neoplastic stromal cells of GCTB. Ongoing in vitro studies suggest that other drugs alone or in combination (e.g. sunitinib) with denosumab may target both the neoplastic and the giant cells. Promising results have been reported regarding the off-label use of denosumab in other giant cell-rich tumours/tumour-like lesions, i.e. aneurysmal bone cysts and central giant cell granulomas. Data are derived, however, mostly from case reports and case series. Large prospective clinical trials are needed to evaluate the role and also the side effects of denosumab in the treatment of these rare diseases.

Does cryotherapy decrease the local recurrence rate in the treatment of an aneurysmal bone cyst? A comparative assessment.

Curettage with or without the use of adjuvants is the standard of care in the treatment of an aneurysmal bone cyst (ABC). Historically, our approach combined curettage, high-speed burr drilling, and cryoablation. However, treatments varied based on age, tumor location, and surgeon preference. We asked: (1) Does cryoablation in addition to curettage and burr drilling decrease the local recurrence rates? (2) Are there any risk factors for the local recurrence rate? (3) Does cryoablation improve postsurgical functional outcomes in these patients? Patients treated for an ABC, between January 2006 and December 2019 were included in this retrospective analysis. Patient and surgical characteristics, such as age, gender, tumor location, type of treatment, time of follow-up, recurrence rate, and functional outcome measured by the Musculoskeletal Tumor Society Score 1993 (MSTS93) score were compared between those treated with and without cryoablation. Both groups, without cryoablation (n = 88) and with cryoablation (n = 42), showed no significant difference in local recurrence rates (9.1% vs. 7.1%, p = 0.553) and functional outcomes as measured by the MSTS93 score (28.9 vs. 27.8, p = 0.262). Risk factors analyzed did not significantly affect local recurrence risk, except for secondary ABC diagnosis (p = 0.017). The cryoablation group had a more extended follow-up (45.6 vs. 73.2 months, p < 0.001), reflecting a shift in practice over time. We found no significant difference in local recurrence rate or functional outcome in patients treated with or without cryoablation. Formal curettage with additional high-speed burr drilling provides effective tumor control and favorable functional outcomes, negating the need for adjuvant cryoablation.

Denosumab-Induced Rebound Hypercalcemia Treated With Bisphosphonates in a Pediatric Patient.

Denosumab is a RANK-L inhibitor used off-label as a treatment for a variety of pediatric bone disorders, including aneurysmal bone cysts (ABC). Rebound hypercalcemia is a known side effect after denosumab therapy and is more commonly reported in pediatric patients. Although there are no established treatment guidelines, denosumab-induced rebound hypercalcemia is usually managed with a combination of intravenous fluids, diuretics, corticosteroids, denosumab, and/or bisphosphonates. We present the case of a 10-year-old female patient with history of a right sacral ABC treated with denosumab who presented with recurrent episodes of rebound hypercalcemia beginning 3 months after denosumab cessation. After the third hospitalization for hypercalcemia, which was treated with zoledronic acid, normocalcemia was achieved. This case demonstrates an increasingly recognized side effect of denosumab therapy that occurs mainly in skeletally immature patients and presents a possible approach to initial therapy of rebound hypercalcemia with a long-acting bisphosphonate.

Restoration of Limb Length Discrepancy and Alignment With the Ilizarov Device After Management of an Aneurysmal Bone Cyst Crossing the Distal Femoral Physis.

An aneurysmal bone cyst (ABC), when located juxta-physeal, may rarely penetrate the growth plate and extend into the epiphysis. The recurrence rate is considered higher when ABC is in contact with the active growth plate. Treatment methods usually focus on cyst healing and the rate of cyst recurrence. We present the method of treatment used for addressing the lesion of the growth plate following the surgical management and healing of a juxta-physeal ABC. A seven-year-old girl had an aggressive ABC in the juxta-physeal area of the distal femur, penetrating the growth plate and extending in the epiphysis. Surgical treatment was performed, including curettage and autologous bone grafting, avoiding the growth plate. The cyst healed; however, physis presented an obliteration. The affected limb developed valgus deformity and severe leg length discrepancy (LLD). To address this issue, once our patient completed her growth, we proceeded with distraction osteogenesis, using the Ilizarov device, with asymmetrical lengthening of the rods. We achieved the correction of the limb alignment and resolved the LLD. ABCs in the juxta-physeal area of a growing child are benign metaphyseal tumors that exceptionally may penetrate the physis and extend into the epiphysis. Our report highlights that the growth plate's lesion, despite the cyst's healing, may compromise the final result. The use of the Ilizarov device is an effective method for correcting the malalignment and the LLD that may emerge.