Background  A widely accepted set of imaging criteria or classification has not yet been adopted to evaluate response to treatment by percutaneous sclerotherapy for aneurysmal bone cyst (ABC). In this article, we described and illustrated the Royal Orthopaedic Hospital (ROH) scoring system which is a new, reproducible, and objective tool to evaluate the radiological response. We also reported our institutional experience in the efficacy of computed tomography (CT)-guided sclerotherapy for treating such lesions. Patients and Methods  A retrospective analysis was conducted for 19 patients who underwent CT-guided sclerotherapy with doxycycline and albumin to treat ABC. Follow-up magnetic resonance imaging, at a minimum of 12 months, was assessed according to the four ROH scoring system parameters: cystic component, fluid-fluid level, presence of consolidation, and cortical integrity. The cumulative score was used to grade response as either: excellent, good, equivocal, or poor. Results  Out of 19 patients with a mean age of 17.8 years, 11 cases occurred in the long bones, 5 cases in the pelvis, and 1 in each of the C3 vertebral body, scapula, and talus. The mean parameter of response score for cystic component was 2, fluid-fluid level was 1.3, consolidation was 2, and cortical integrity was 2.1. Four cases showed excellent response, 12 cases showed good response, 2 cases showed equivocal response, and 1 case showed poor response. Interrater reliability was excellent (κ = 0.9). Conclusion  The ROH scoring system provides the radiologist and surgeon with an objective method to score imaging parameters of response independently and achieve a grade based on the cumulative score.

UNASSIGNED: Polidocanol sclerotherapy in the treatment of aneurysmal bone cysts (ABCs) with or without pathological fractures has been a topic of debate. While some studies recommend intralesional curettage as the preferred treatment, others suggest intralesional sclerosants as an effective alternative.
UNASSIGNED: This study evaluates the use of polidocanol-based percutaneous sclerosant therapy in 28 patients with ABCs, of which 8 patients had pathological fracture. The patients received injections every four weeks based on clinical and radiological evaluation of the cyst, and the study assessed the results and complications of the treatment.
UNASSIGNED: In group A (without pathological fractures), 14 out of 17 (82.4 %) lesions healed without any significant residual lesion. Three out of 17 (17.6 %) patients required further surgical intervention and were treated by curettage and bone grafting, definitively. Minor local inflammatory reaction was observed in 3 patients, which resolved without intervention within 3-4 days. In group B, all the 8 patients (100 %) with pathological fracture in their lesions healed as Grade 1 healing, without any significant residual lesion. One patient developed an episode of anesthesia related complication (delayed recovery) which resolved within an hour, without any residual effect. At final follow up, no recurrence was seen in any patient.
UNASSIGNED: The study concludes that polidocanol sclerotherapy is an effective treatment option for patients with ABCs, with or without pathological fractures, and has the potential to become the new treatment of choice for pathological fractures due to its low invasiveness, low morbidity, and affordability. However, further research is needed to confirm the efficacy of polidocanol sclerotherapy in larger patient populations and to compare its effectiveness with other treatment options.

BACKGROUND: Since giant cell tumors of bone (GCTB) and other giant cell rich tumors of bone (GCRTB) share the histological presence of osteoclastic giant cells and expression of RANK/RANKL, we hypothesized that GCRTB will respond similarly to denosumab as GCTB. The primary objective of this study was to determine the efficacy of denosumab in patients with GCRTB that have recurred or require morbid surgery.
METHODS: In this open-label, multicenter, phase II trial, patients with GCRTB were included (June 2018-March 2020). Recruitment was stopped because of low accrual. Patients received denosumab (120 mg) subcutaneously (SC) on day 1 of every 4-week cycle with a loading dose of 120 mg SC on days 8 and 15.
RESULTS: Three patients were enrolled. One withdrew consent before start of study. The remaining patients had central giant cell granuloma of the jawbone (CGCG). Median treatment duration was 15 cycles (range 12-18). In both subjects, improvement in ossification of lesions was seen. Median follow-up was 28.5 months (range 20-37). One patient developed a recurrence for which surgery was performed.
CONCLUSIONS: Due to critical emerging real-world data of denosumab in GCRTBs, the study was prematurely stopped and not supportive of use of denosumab for this indication. (ClinicalTrials.gov Identifier: NCT03605199).

BACKGROUND: The aneurysmal bone cyst (ABC) is a benign, but locally aggressive cystic lesion of the bone. It usually occurs in the metaphysis of long bones of adolescents and young adults but can also affect the pelvis.
METHODS: This single-center study is a retrospective review of 17 patients with primary ABCs of the pelvis. It examines the importance of polidocanol instillations as minimally invasive treatment option for ABCs of the pelvis compared to intralesional curettage or marginal resection.
RESULTS: Seventeen patients with the diagnosis of a primary ABC of the pelvis were included in the study. Six patients were male (35%) and 11 patients female (65%); the mean age was 18 (9-49) years. The mean follow-up time was 50 months (12-136 months). The most common location of manifestation was the pubis (6; 35%), followed by the ilium (6; 35%), the sacrum (3; 18%) and the ischium (2; 12%). Eight patients were treated by intralesional curettage with the use of adjuvants, one patient by marginal resection, seven by sequential instillation of polidocanol and one patient by simple observation. Five patients received an additional transarterial embolization. After intralesional curettage local recurrence was detected in 4/8 cases (50%). After instillation therapy six patients (86%) had a stable disease without recurrence, only one patient (14%) had a persistent disease with need of additional treatment and was therefore converted to intralesional curettage without local recurrence in the follow-up.
CONCLUSIONS: Sequential instillations of polidocanol are a promising, minimally invasive treatment method for ABCs of the pelvis and can be well combined with transarterial embolization.

OBJECTIVE: Aneurysmal bone cyst (ABC) and telangiectatic osteosarcoma (TOS) share several clinical and imaging features, including young presentation, long bone involvement, lytic appearance on radiography and fluid-fluid levels on MRI. Therefore, they may be difficult to differentiate. The aim of this study is to identify clinical, radiological and MRI features which aid differentiation of the two lesions.
METHODS: Retrospective review of all histologically confirmed ABC and TOS over an 11-year period. Data recorded include age at presentation, sex, skeletal location and various radiographic and MRI features.
RESULTS: This retrospective study included 183 patients, 92 males and 91 females. Mean age at presentation of 18.4 years (range 1-70 years); 152 cases of ABC and 31 TOS. No significant difference between age and sex. TOS was significantly less likely to involve the axial skeleton; no difference related to location within the bone. Radiographic findings significantly favouring ABC included a less aggressive pattern of bone destruction, a purely lytic appearance, an expanded but intact cortex, no periosteal response and no soft tissue mass. MRI features significantly favouring ABC included smaller tumour size (maximum mean dimension 46 mm compared to 95 mm for TOS), absence of soft tissue mass, > 2/3 of the lesion filled with fluid levels and thin septal enhancement following contrast.
CONCLUSIONS: Several radiographic and MRI features aid in the differentiation between ABC and TOS. Lesions with a geographic Type 1A or IB pattern of bone destruction which are completely filled with FFLs on MRI can confidently be diagnosed as ABC.

Aneurysmal bone cyst (ABC) is defined as a benign lesion of bone containing blood-filled channels divided by soft-tissue septa and mostly diagnosed in children and adolescents. In the present study, the case of a 7-year-old girl with spastic paraparesia and left foot drop was investigated. Spinal imaging revealed a large lytic mass in the posterior elements of the T2 vertebral body, which resulted in the partial collapse of the T2 vertebral body, a T1 to T3 dislocation, and a spinal sagittal imbalance. The patient underwent a two-stage surgical procedure including an anterior T2 corpectomy, T1/T2 and T2/T3 discectomy, anterior instrumentation, posterior total tumor resection, and posterior fixation with laminar hooks. Postoperative imaging demonstrated cord decompression and good spinal alignment. Although a spinal ABC is a rare entity, it can occur in any segment of the spinal column and cause cord compression and spinal instability. Thus, proper treatment planning is crucial for total tumor resection to avoid tumor recurrence and correct spinal imbalance.

OBJECTIVE: The aim of the present study was to analyze clinical, radiological and histopathological features of aneurysmal bone cysts (ABCs) of jaws.
METHODS: Archival data from 2009 to 2012 present in the Oral Pathology Department was retrieved and clinicopathological features of all the cases which had been previously diagnosed as ABC were analyzed in detail.
RESULTS: Seven cases ranging in age from 10 to 50 years were included, in which maximum (5/7) cases were below 20 years. Ratio of presentation of lesion in male to female and in maxilla to mandible was 3:6 and 1:6 respectively. Swelling and pain were the most common presenting features. Variable presentation of the lesion was observed radiographically; although multilocular, well defined, bone expansion and perforation were the most common observations. Histopathological analysis revealed association of one case with ossifying fibroma and two cases with trabecular variety of juvenile ossifying fibroma. Predominance of solid variety was noted and other features like stroma, giant cells, nature of blood vessels, bone destruction and perforation and presence of any osteoid or calcified material was also accounted for. The current study showed association of two cases with trabecular variety of juvenile ossifying fibroma, which is a rare finding.
CONCLUSIONS: ABCs of jaws, thus have varying patterns of presentation which are diagnostically challenging. A thorough examination of the incisional/excisional tissue is thus required to confirm the association with any other lesion which will affect the treatment plan for the patient.

OBJECTIVE: To evaluate the long-term tolerance of bisphosphonates proposed as an alternative therapeutic option for symptomatic unresectable benign bone tumors and to evaluate the long-term efficacy of this treatment.
METHODS: From March 2007 to March 2011, patients with unresectable symptomatic benign bone tumors were consecutively included in this institutional review board-approved study and treated with bisphosphonates. Prospectively long-term follow-up is reported. The study endpoints were to describe the long-term tolerance, the clinical evolution of pain for each patient and the radiological success defined as a complete disappearance of inflammation and ossification of the bone lesion. All complications and side effects were recorded.
RESULTS: Eight patients (mean age 16 years; range 7-42) with various tumor subtypes were included: aneurysmal bone cysts (N=5), Langerhans cell histiocytosis (N=1), osteoblastoma (N=1), and a giant cell tumor (N=1). Tumors were located in cervical (N=4) or thoracic (N=1) vertebrae, femoral shaft (N=1), acetabulum (N=1) and sacrum (N=1). Mean number of bisphosphonate cycles was 3 (range: 1-6) over a median period of 10 months. The median clinical and imaging follow-up period was 21 months (6 to 63 months). No severe complications due to treatment or lesion recurrence were reported. Pain disappeared within 6 weeks of the first cycle for all but one patient. Ossification of the bone lesion was observed for all patients but one, complete for two and partial for the five others.
CONCLUSIONS: Bisphosphonates appear to be an effective option without adverse effects for the non-operative management of symptomatic benign bone tumors.