Background/Objective: Surgical treatment of aneurysmal bone cysts (ABCs) can be challenging, especially in the spine. Non-surgical treatments such as with denosumab have shown promising results in different osteolytic pathologies. This retrospective observational study aimed to evaluate the long-term clinical and radiologic response of patients with ABCs of the mobile spine treated with denosumab and propose an updated treatment algorithm. Methods: Six patients with relapsed and symptomatic ABCs of the mobile spine were treated with denosumab (120 mg subcutaneously on days 1, 8, 15, 29, and every 4 weeks thereafter) between 2012 and 2023. Disease assessments were conducted using CT and MRI at 3, 6, 9, and 12 months post-treatment. Clinical data, including pain levels, symptoms, and adverse events, were documented from patients\' charts. Results: Patients underwent an initial phase of treatment with denosumab, receiving a mean of 22 administrations (range 13-42) over a median follow-up period of 41 months (range 15-98 months). Clinical improvement was observed in all patients after 4 weeks of treatment, and all patients demonstrated a radiological response after 12-24 weeks on denosumab. Three patients were progression-free after discontinuing denosumab following 13, 15, and 42 administrations, respectively. At the last follow-up, after 38, 43, and 98 months, these patients remained stable without relapse of the disease. Three patients had a relapse of disease after denosumab; two of them underwent denosumab re-challenge, while one patient received one mesenchymal stem cells (MSCs) injection. All patients showed clinical and radiological improvement and were resulted to be disease-free at the last follow-up. Conclusions: This study demonstrates the long-term efficacy and safety of denosumab in treating ABCs of the mobile spine, as well as the potential of re-challenge in managing recurrence. A treatment algorithm is proposed, positioning denosumab as a viable therapeutic option after other local treatments. Careful patient selection, monitoring, and further research are necessary to optimize denosumab use for ABCs.

UNASSIGNED: Aneurysmal bone cyst (ABC) is a benign lytic bone tumor of the skeletal system but locally destructive lesion of unknown origin. It often occurs in childhood and usually involves the metaphyseal region of long bones; thus, its localisation in the calcaneum remains rare; its atypical presentation in our case makes it remarkable.
METHODS: We describe a case of a young patient who suffered from chronic heel pain, in whom the clinical examination finds swelling and pain on palpation. A complete radiological assessment was carried out, which revealed a solitary and expansive osteolytic lesion within the calcaneus. Treatment included tumor curettage and reconstruction with allograft and cement. The biopsy report was consistent with an ABC. The postoperative follow-up at 18 months was marked by a good radio-clinical evolution and no recurrence.
UNASSIGNED: ABCs are benign cystic expansive tumors that are reactive, locally destructive and blood-filled, their occurrence in the calcaneus has been reported in only 1.6 % of total reported cases. Talalgia is the most frequent sign associated with swelling. Liquid-liquid level images on MRI is a pathognomonic sign of these lesions but the gold standard diagnosis remains histology. Their treatment is based on curettage - filling by grafting.
CONCLUSIONS: Curettage combined graft makes results butter and improves the quality of life.

Aneurysmal bone cysts (ABCs) are uncommon benign bone lesions that consist of blood-filled vascular spaces surrounded by fibrous tissue septa. Their diagnosis and surgical management are challenging in a war-torn region. In this case report, we present a rare case of a giant aneurysmal bone cyst located around the acetabulum in a 10-year-old female child who presented with an antalgic limp and left hip pain. The lesion was successfully treated with curettage and mixed autologous and synthetic bone grafts, and the follow-up for two years revealed a complete resolution of symptoms and radiological evidence of bone regeneration. This case highlights the successful surgical treatment of a challenging case of ABC in a difficult setting during the Syrian conflict.

The purpose of this review is to increase awareness about the evolution and development of current trends in the diagnosis and treatment of aneurysmal bone cysts (ABCs). ABCs are benign, but locally aggressive bone tumors that mainly affect children. ABCs comprise 1% of all primary bone tumors and occur most frequently during the first two decades of life. The diagnosis is made using a variety of imaging modalities and has the characteristic features of an expansile, radiolucent lesion that is often seen in the metaphyseal region of the bone and has fluid-fluid levels that are apparent on MRI. In the pediatric population, telangiectatic osteosarcoma and unicameral bone cyst (UBC) are the main differential diagnoses of an ABC. Giant cell tumors (GCTs) also include in differential diagnosis, which often manifest in patients older than 15 and do not penetrate the open physis although they develop after the physeal closure. Imaging alone cannot rule out telangiectatic osteosarcoma; therefore, a biopsy is recommended. A variety of treatment options have been described; traditionally, most patients are treated with curettage and bone grafting. Curettage alone, however, usually results in tumor recurrence following excision. A variety of adjuvants have been utilized with varying degrees of effectiveness to reduce the risk of local recurrence. When a cyst is in the pelvis, its location and size are such that surgery is a very risky option. Selective arterial embolization has significantly contributed to the development of effective treatments for these situations. Embolization or radiation, as well as denosumab therapy, are widely used as therapies for ABCs in anatomic locations where surgery would significantly increase morbidity.

UNASSIGNED: Aneurysmal bone cysts (ABCs) are non-neoplastic expansile, vascular, osteolytic benign tumors in the long bone, spine, and sternum. The location in the pelvis is sparse.
UNASSIGNED: A 12-year-old female presented with pain in her left pelvis for 6 months. On radiological examination, we found an expansile balloting lytic lesion involving almost the whole ilium and sparing the hip joint. There were multiple fluid levels seen on magnetic resonance imaging. The initial biopsy suggested ABC. Curettage and bone grafting were done along with electrocauterization and chemical cauterization. At 1-year follow-up, she is doing well without any complaints.
UNASSIGNED: This case report demonstrates a rare ABC of the ilium that was managed with curettage and bone grafting.

BACKGROUND: Percutaneous treatment for primary aneurysmal bone cysts (ABCs) has been widely accepted. The study aimed to evaluate the efficacy of various sclerotherapy agents on patients with primary ABCs.
METHODS: A meta-analysis of relevant studies. A systematic search was conducted on five databases, resulting in the inclusion of 25 studies with different percutaneous agents.
RESULTS: A total of 729 patients with primary ABCs were included. Patients were administered with Ethibloc, doxycycline, embolization, alcohol, polidocanol, and calcitonin with methylprednisolone, respectively. Overall, 542 (74.3%) patients with ABCs had complete healing, 120 (16.4%) had partial healing, 44 (6%) had no-ossification or failure, and 26 (3.5%) had a recurrence. However, there was a total of 45 (6.1%) patients who had surgical curettage after sclerotherapy. Among the sclerotherapy agents, doxycycline showed highly effective results with minimal complications and recurrence, but it required multiple injections per patient. Ethibloc and embolization also proved to be highly effective with fewer injections required but had a higher rate of complications. Absolute alcohol, polidocanol, and calcitonin with methylprednisolone had similar efficacity and favorable success with fewer complications and fewer injections.
CONCLUSIONS: Percutaneous treatment showed promising results in treating primary ABCs. However, more robust research is needed to establish the best approach for sclerotherapy in clinical practice and to address the limitations of the current literature.

OBJECTIVE: The aim of this study was to evaluate treatment efficacy of percutaneous injection of hydroxyapatite-osteoconductive-cement in patients with spinal aneurysmal bone cysts.
METHODS: The study was designed as a retrospective observational clinical study. We included patients who were diagnosed with of spinal aneurysmal bone cyst, at our institution between 2013 and 2020, and treated with percutaneous injection of osteoconductive cement: \"Cerament\"® (BONESUPPORT AB, Lund, Sweden). Typical clinical and radiological features of the ABCs treatment and follow-up were investigated.
RESULTS: Our study included nine patients, two children and seven adults. Three different types of approaches were applied: (single pedicle approach in 3 patients; double pedicle approach in 2 patients; while in the remaining cases, a multiple access approach was used. VAS score decreased from 8.5 ± 0.5 before treatment to 4.1 ± 0.9 at 6-months-follow up. All of the patients reacted well to treatment, with none neurological complications, complete loss of pain and achieved osteosclerosis as radiological marker of treatment success.
CONCLUSIONS: Treatment of symptomatic spinal ABC\'s with hydroxyapatite cement is effective to achieve complete pain reduction and sclerosis.

Of all primary spine tumors, 15% are benign osteolytic lesions known as aneurysmal bone cysts (ABCs). Owing to the involvement of surrounding neurovascular structures and the potential for cervical spine instability, ABCs in the cervical spine represent a relatively uncommon clinical entity with surgical resection that is extremely challenging. This report details a case of an ABC in the cervical spine affecting a 10-year-old child who presented at the Medical Services Center at Imam Muhammad Ibn Saud Islamic University. The patient manifested with neck pain, a history of trauma, limitations in cervical motion, and neurological changes over the course of clinical follow-up. Diagnostic measures included radiography and computed tomography. The child underwent surgery to stabilize the cervical spine and to excise both the tumor and the affected vertebrae. Given the high recurrence rate of previously described lesions, various additional techniques have been utilized in conjunction with surgical resection, such as radiation and embolization. This paper further discusses the patient\'s progress, the chosen treatment, and the range of available options. More research is needed to develop evidence-based treatment plans for cervical spine ABCs in younger patients.

The optimal treatment for aneurysmal bone cysts (ABCs) of the spine remains controversial. No treatment guidelines exist for the use of denosumab in aneurysmal bone cysts. In this report, we describe the results from a representative case and compare our experience with those of previously published reports. A 38-year-old male was referred for pain in the lower back and left leg. Radiographs and a needle biopsy specimen revealed a lumbar aneurysmal bone cyst, which was treated with denosumab chemotherapy. The pain in the lower back and left leg gradually improved, and at 16 weeks, the symptoms had resolved. Once a satisfactory local effect was achieved, denosumab therapy was discontinued. However, the erosive lesion subsequently expanded. After re-initiation of treatment, there was no subsequent evidence of recurrence. Single-therapy denosumab is an option for aneurysmal bone cysts. However, recurrences have been documented after denosumab termination, and the timing for cessation of denosumab is controversial.

OBJECTIVE: The thin and friable septations composing aneurysmal bone cysts (ABC) may be challenging to target for percutaneous biopsy. The purpose of this study was to describe and evaluate a novel method of ABC biopsy using endomyocardial biopsy forceps as an attempt to capture larger fragments of tissue for diagnosis.
METHODS: This was a retrospective study performed over a 17-year period. Patients <18 years old who underwent percutaneous biopsy for a presumed ABC, based on pre-procedure imaging, were included. Medical records were reviewed to identify age, sex, lesion location, biopsy procedure details, complications, and pathology results. A diagnostic biopsy was defined as conclusive histologic confirmation. Inconclusive findings or findings suggestive of but not diagnostic of an ABC were treated as non-diagnostic, even if imaging and clinical findings were characteristic. Biopsy device selection and quantity of tissue obtained was at the discretion of the pediatric interventional radiologist. Fisher\'s exact test was used to compare the diagnostic yield of standard biopsies to those employing biopsy forceps.
RESULTS: Twenty-three biopsies were performed in 18 patients (11 female) with a median age of 14.7 years (IQR 10.6-15.6). Lesions were located in the extremities (7, 30.4%), chest (6, 26.1%), pelvis (5, 21.7%), spine (4, 17.4%), and mandible (1, 4.3%). Specimens were obtained using a 13- or 15-gauge bone coring needle (11, 47.8%); 14-, 16-, or 18-gauge soft tissue needle (6, 26.1%); or a combination of bone and soft tissue (4, 17.4%) needles. Endomyocardial biopsy forceps were utilized in 7 cases (30.4%), 2 in which it was the only device used. Overall, a conclusive pathologic diagnosis was made in 13/23 (56.5%) biopsies. Of the diagnostic biopsies, 1 was a unicameral bone cyst and all others were ABCs. No malignancy was identified. Compared to the standard approach, the use of forceps was more likely to result in a diagnostic biopsy (40.0% vs 100.0%, p = 0.008). There were no complications.
CONCLUSIONS: Endomyocardial biopsy forceps offer an additional, novel technique to biopsy presumed ABCs and may improve diagnostic yield.