Aneurysmal bone cyst: a review of 150 patients

A New Radiological Scoring System as a Method of Assessing Sclerotherapy Treatment Response for Aneurysmal Bone Cysts: A Retrospective Study

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.

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.

Maxillary Aneurysmal Bone Cyst in a Young Dog-A Case Report

This case report describes an aneurysmal bone cyst in the maxilla of a young dog. It describes the clinical presentation, diagnostics, management, and successful outcome of this highly unusual case. Bone cysts are described as benign, cavitated lesions within bone that are lined by reactive tissues. There is no epithelial lining in the lesions. Bone cysts usually contain hemorrhage or serosanguinous fluid. They usually appear in the long bones, and present as a swelling with or without pain.

Pathological Fractures in Aneurysmal Bone Cysts: A Systematic Review

Background: Aneurysmal bone cysts (ABCs) are osteolytic, non-malignant, vascular lesions of the bone. Pathological fractures can be a manifestation of the ABCs, which occur in about 8% of ABCs. Different treatments have been described in the literature, but, nowadays, an optimal management of the pathological fractures in patients with ABCs is still a matter of debate and there are no standard guidelines for treatment nor any shared indication about the best surgical intervention. The aim of our study is to review the current literature available on this matter exploring and confronting different surgical treatments for pathological fractures in ABC in order to clarify the surgical approach to these patients. Methods: A systematic review of the literature indexed in PubMed, MEDLINE, and Cochrane Library databases was carried out. The Preferred Reporting Items for Systematically Reviews and Meta-Analyses (PRISMA) were followed. Results: A total of 37 articles were relevant and were finally included in the study. In total, we reached a population of 140 patients. Of the 140 patients included in the review, 124 patients (88.6%) underwent curettage surgery, 15 patients (10.7%) underwent en bloc resection surgery. A total of 47% of patients (70) underwent synthesis surgery with a plate, screw, nail, or external fixator. Adjuvant treatments were used in 8.6% of patients (12). Complications involved 20.7% of the patients (29). Conclusions: In conclusion, the treatment of pathological fractures in aneurysmal bone cysts requires careful patient assessment, considering factors such as age, the presence of open growth plates, the location of the lesion, and the surgeon's expertise.

Denosumab and sclerotherapy for recurrent spinal aneurysmal bone cyst in a child

Aneurysmal bone cyst (ABC) is a non-malignant, locally destructive, blood-filled lesion in the bone that tends to grow aggressively. A young girl presented with a rapid recurrence after aggressive surgery of a large symptomatic sacral-spinal ABC. After a multidisciplinary tumour board, she was successfully treated with sclerotherapy and monthly intravenous denosumab. The patient has maintained asymptomatic for over 36 months now and has returned to full activity and strength. She never required surgery and has had radiologic resolution of the lesions. Treatment of recurrent ABC requires a multidisciplinary team approach. We believe this to be the first report to use this combined therapy to provide an alternative to morbid surgery for children with ABCs.

Current Concepts in the Treatment of Giant Cell Tumor of Bone: An Update

Curettage is recommended for the treatment of Campanacci stages 1-2 giant cell tumor of bone (GCTB) in the extremities, pelvis, sacrum, and spine, without preoperative denosumab treatment. In the distal femur, bone chips and plate fixation are utilized to reduce damage to the subchondral bone and prevent pathological fracture, respectively. For local recurrence, re-curettage may be utilized when feasible. En bloc resection is an option for very aggressive Campanacci stage 3 GCTB in the extremities, pelvis, sacrum, and spine, combined with 1-3 doses of preoperative denosumab treatment. Denosumab monotherapy once every 3 months is currently the standard strategy for inoperable patients and those with metastatic GCTB. However, in case of tumor growth, a possible malignant transformation should be considered. Zoledronic acid appears to be as effective as denosumab; nevertheless, it is a more cost-effective option. Therefore, zoledronic acid may be an alternative treatment option, particularly in developing countries. Surgery is the mainstay treatment for malignant GCTB.

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.

Diagnosis and Current Treatment of Aneurysmal Bone Cysts

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.

The Role of En Bloc Resection in the Modern Era for Primary Spine Tumors

STUDY DESIGN

A literature review.

OBJECTIVE

The aim of this review is to provide an overview of benign and malignant primary spine tumors and a balanced analysis of the benefits and limitations of (and alternatives to) surgical treatment with en bloc resection.

SUMMARY OF BACKGROUND DATA

Primary spine tumors are rare but have the potential to cause severe morbidity, either from the disease itself or as a result of treatment. The prognosis, goals, and treatment options vary significantly with the specific disease entity. Appropriate initial management is critical; inappropriate surgery before definitive treatment can lead to recurrence and may render the patient incurable, as salvage options are often inferior.

METHODS

We performed a comprehensive search of the PubMed database for articles relevant to primary spine neoplasms and en bloc spine surgery. Institutional review board approval was not needed.

RESULTS

Although Enneking-appropriate en bloc surgery can be highly morbid, it often provides the greatest chance for local control and/or patient survival. However, there is growing data to support modern radiotherapy as a feasible and less morbid approach to certain primary neoplasms that historically were considered radioresistant.

CONCLUSIONS

Choosing the optimal approach to primary spine tumors is complex. A comprehensive and up-to-date assessment of the evidence is required to guide patient care and to balance the often-competing goals of prolonging life and preserving quality of life.

Use of Surgical Adjuvants Does Not Decrease Recurrence of Aneurysmal Bone Cysts in Surgical Intervention With Pediatric Patients

BACKGROUND

Aneurysmal bone cysts (ABCs) are benign active tumors often requiring intralesional curettage with or without adjuvants. The primary aim of this study was to analyze whether recurrence is influenced by the use of surgical adjuvants in pediatric patients with ABCs. Secondary aims examined recurrence rates based on age, sex, and physeal contact.

METHODS

A retrospective review was performed at a tertiary pediatric hospital from 2004 to 2020. Inclusion criteria consisted of patients treated surgically for histologically confirmed ABCs with a minimum of 6 months follow-up. Patients with treatment for a recurrent tumor or incomplete records were excluded. Patient demographics, location of the lesion, treatment technique, and incidence of recurrence were collected. Statistical analyses were performed using STATA.

RESULTS

There were 129 patients (74 males and 55 females) with a mean age of 11.5 ± 4.1 years and an average follow-up of 29.0 ± 25.4 months. The most common locations for ABCs were the femur and tibia. Of the patients, 53.5% had tumors abutting the physis, 28.7% had no physeal contact, and 17.8% had insufficient imaging to evaluate physeal contact. Surgical adjuvants (high-speed burr, coagulation, liquid nitrogen, and/or hydrogen peroxide) were used in 91 of the 129 cases (70.5%). There was no significant difference in recurrence when comparing those who received an adjuvant and those who did not (25.3% vs 23.7%, P = 1.000). Physeal contact was also not significantly associated with recurrence ( P = 0.146). Finally, patients younger than 6 years old were significantly more likely to have recurrence compared with those 6 years old or older (66.7% vs 21.7%, P = 0.007).

CONCLUSION

Our study found no association between the use of surgical adjuvants and the risk of recurrence after intralesional curettage for ABCs. Although our study did demonstrate that patients 6 years old or younger had an increased rate of recurrence, no significant association was found regarding physeal contact or sex. These data indicate that surgical adjuvant may not affect the recurrence rates of pediatric patients with ABCs.

LEVEL OF EVIDENCE

Level III. This retrospective review compares rates of recurrence based on the choice of surgical adjuvant.

Aneurysmal bone cyst: Is selective arterial embolization effective as curettage and bone grafting?

INTRODUCTION

Aneurysmal bone cyst (ABC) is a lytic benign bone lesion representing about 1% of all primary bone tumors. Method to treat ABC's have developed over time. The standard of care cure for ABC has been curettage with or without bone grafting of the defect but is burdened by recurrence rates of approximately 25%-31%. Based on the assumption that ABCs usually supplied by one or more pathological feeding arteries, selective arterial embolization has been described as an adjuvant preoperative procedure to reduce intra-operative hemorrhage, and as primary treatment for lesions in difficult surgical access. In the current study, we therefore asked whether (1) a single or a repeat selective arterial embolization (SAE) for treating ABCs would produce comparable healing rates compared with curettage and bone grafting; (2) evaluated the relationship of recurrence in relation to the site of the cyst, the age, and gender of the patients; and (3) the two techniques differ in term of long-term complication.

MATERIAL AND METHODS

We retrospectively reviewed 265 patients who underwent curettage and bone grafting or SAE performed at our institute from 1994 to 2018. The diagnosis of ABC was always established with percutaneous CT-guided biopsy or open biopsy. Patients were followed clinically with plain radiographs or CT scan at 3, 6, 9, and 12 months then annually in the absence of symptoms. Treatment success was determined evaluating pre- and postprocedural imaging according to Chang classification.

RESULTS

Two hundred and nineteen were treated with curettage and bone grafting (curettage group), and 46 with SAE Group. Of the 219 patients treated with Curettage and bone grafting (curettage group), 165 out of 219 (75.3%) experienced bone healing, while local recurrence was observed in 54 cases (24.7%) after 12 months on average (range: 3-120 months) from surgery. After the first SAE, bone ossification was seen in 27 (58.7%), without needing any further treatment. Eleven recurred patients were treated with SAE (four patients need two while seven need three SAE to heal), and eight patients with curettage and bone grafting. Thirty-eight out of 46 (82%) patients experienced bone ossification regardless the number of SAE. The overall rate of local recurrence for all patients was 26.7%. SAE group presented a lower complication rate (6%) where two patients experienced skin necrosis, and one limb-length discrepancies (2% of all cohort).

DISCUSSION

The use of SAE is an attractive option to treat ABC as it combines on one hand a lower complication rate than curettage and bone grafting, on the other it can be carried out in case of nonresectable ABCs, significantly reducing the size of viable ABC lesions, fostering bone remodeling and mineralization, and most importantly, significantly improving the patient's quality of life.

Treatment of Spinal Aneurysmal Bone Cyst with Percutaneous Injection of Hydroxyapatite Osteoconductive Cement

PURPOSE

The aim of this study was to evaluate treatment efficacy of percutaneous injection of hydroxyapatite-osteoconductive-cement in patients with spinal aneurysmal bone cysts.

MATERIALS AND 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.

CONCLUSION

Treatment of symptomatic spinal ABC's with hydroxyapatite cement is effective to achieve complete pain reduction and sclerosis.

Management of advanced metacarpal aneurysmal cysts: Surgical technique

The hand is a rare site for aneurysmal bone cysts (ABCs). Depending on their degree of invasiveness, treatment of ABCs ranges from medical therapy to surgical curettage and bone filling. In the most advanced cases, bone resection and reconstruction, with or without adjuvant or neoadjuvant treatment, are indicated. We describe a technique involving segmental bone resection and structural iliac graft reconstruction with carpo-metacarpal plate arthrodesis, for the management of advanced ABC involving the base of the metacarpals. The radio-clinical results of two patients operated on using this technique are presented, at 18 and 36 months. At the last follow-up, the results showed a QDASH of 15 and 10, and a PRWE of 9 and 11. Satisfaction was 10/10 in both cases. Grasp strength was 25 kg and 42 kg versus 28 kg and 40 kg on the opposite side. Pinch strength was 6 kg and 11 kg versus 7 kg and 10 kg. Metacarpophalangeal flexion was 80° and 90°. Extension was complete in both cases. Radiographs showed good graft fusion, with no lysis or signs of ABC recurrence at the last follow-up. Segmental bone resection and iliac autograft reconstruction with carpo-metacarpal plate arthrodesis represents a therapeutic option in the management of advanced ABCs of the metacarpal base.

Middle cranial fossa tumor presenting as chronic otitis media: Rare case of aneurysmal bone cyst

INTRODUCTION

Aneurysmal bone cysts (ABCs) are a rare, vascular, rapidly growing, benign, osteolytic lesions. Most ABCs involve the metaphysis of long bones, vertebrae, or flat bones. In this study, we review the literature to better understand the natural history, clinical presentation, and treatments.

PRESENTATION OF CASE

A 34-year-old man who presented with left intermittent otorrhea for months. Yellowish, pus-like discharge was noted. Mild tinnitus, hearing loss, and occasional headache was also found. The initial impression was chronic otitis media and ear drops were prescribed. However, his symptoms did not improve in the following months. The brain MRI with gadolinium enhancement revealed an extra-axial mixed signal intensity lesion on the T2-weighted image, multiloculated cystic components and rim enhancement was noted over the left middle cranial fossa. Left fronto-temporal craniotomy for tumor removal was performed. The pathological reports revealed an aneurysmal bone cyst.

CLINICAL DISCUSSION

Typically, ABCs present with localized swelling and pain due to their rapid growth and expansion, with concomitant signs corresponding with the anatomical location of the lesion. MRI studies can reveal the cystic components of the lesion and multiple fluid levels within multiloculated cysts resulting from unclotted blood, separated from the soft tissue and medullary bone. Histopathologic diagnosis of ABC is the presence of multiple blood-filled cystic spaces separated by fibrous septa. The fibrous septa are composed of spindle-celled fibroconnective tissue with occasional osteoclast-type giant cells.

CONCLUSION

ABCs are a rare, osteolytic lesions that rarely involve the skull. When the MRI shows a lesion with soap-bubble appearance in the calvaria, an aneurysmal bone cyst should be considered in the differential diagnosis, even if it is an extremely rare entity or the patient is relatively old. Surgical resection of the tumor is the first choice for treatment.

Interest of preoperative embolization of aneurysmal bone cyst (ABC): A case report

Aneurysmal bone cyst (ABC) is a rare lesion that primarily affects young adults and children. The optimal treatment approach for ABC remains controversial and varies depending on the preferences of the medical team. While some advocate for surgery as the treatment of choice, others recommend a less invasive first-line option such as selective embolization. In this case report, we present the case of a 41-year-old female patient with an ABC in the right iliac bone who underwent surgical treatment following preoperative selective embolization. Additionally, we provide a literature review on the topic.

Primary aneurysmal bone cyst of hands and feet: A series of 14 cases

Aneurysmal bone cyst (ABC) is a relatively rare, benign bone tumor that occurs exceptionally in the hands and feet. The objective of this article is to present clinical, radiological, histopathological features and management of a series of 14 primary ABC cases in these unusual locations. Eight cases occurred in hands and six in feet. We present the first reported subungual case to occur in the hand. The average age of the patients was 26 years (range 7 to 49), with half being over the age of twenty at diagnosis. The male to female ration was 9:5. In radiological terms, ABC appeared as an expansive lesion with internal septa and without cortical disruption. Twelve cases displayed the classic multicystic morphology and two cases were of the solid variant. "Blue bone" was detected in 50 % of the specimens. Treatment consisted of curettage, excision, or amputation in all cases. Recurrence rate was observed in 35 % of the cases, with the similar ABC morphology as the original samples. New therapeutic options have been proposed on their own or in combination with surgery to reduce local recurrence rates.

Aneurysmal Bone Cyst of the Pelvis in Children and Adolescents: Effectiveness of Surgical Treatment with Curettage, Cryotherapy and Bone Grafting

BACKGROUND

Aneurysmal bone cysts (ABCs) are benign but locally aggressive cystic lesions of the bone. Pelvic ABCs are extremely rare and hard to treat due to their high risk of local recurrence and the tough access to pelvic bones.

METHODS

In this retrospective study, we evaluated pediatric cases with pelvic ABC treated with curettage, cryotherapy and bone grafting treated in our institution between 2016 and 2022. Complications were recorded, as well as local recurrences. Patients' post-operative functionality was assessed with the MSTS score.

RESULTS

Fourteen consecutive cases were included in our study. Their mean age at surgery was 13.5 years. The mean lesion size was 55 mm. The mean follow-up was 38 months. Two cases (11.8%) had local recurrences, which were successfully treated with further curettage. At their latest FU, 13 cases were continuously disease free (CDF), and one had no evidence of disease (NED). Only one case had a post-operative compilation (wound dehiscence). Patients' mean post-operative MSTS score was 29.6.

CONCLUSIONS

Pelvic ABCs are a challenge, even for the most experienced orthopedic surgeon. Our study suggests that the association of an accurate curettage, intraoperative cryotherapy and bone grafting can be a reliable and effective therapeutic option for large-sized ABCs of the pelvis.

Sclerotherapy as a primary or salvage procedure for aneurysmal bone cysts: A single-center experience

BACKGROUND

Aneurysmal bone cysts (ABC) are benign cystic bone tumors of an osteolytic and locally aggressive nature. As an alternative to the primary treatment of choice, which consists of curettage with bone grafting, alternative treatment methods with promising results have been described. At our department, we have, in recent years, used percutaneous sclerotherapy with polidocanol. The objective of this study was to identify the healing rate and safety of sclerotherapy with polidocanol.

AIM

To identify the efficacy and safety of sclerotherapy with polidocanol in primary and recurrent ABC.

METHODS

Twenty-two consecutive patients (median age 12.5 years; range 1-27) with 23 ABCs treated with sclerotherapy with polidocanol from 2016-2021 were included retrospectively. Eleven patients (48%) had undergone different forms of previous treatment with recurrence. Under general anesthesia and fluoroscopic guidance, repeated percutaneous injections of 4mg polidocanol/kg body weight were performed. Through review of the electronic medical records, the following were identified: healing and recurrence rate, number of treatments, gender, age, comorbidity, location of the tumor and side effects / complications, as well as any previous surgery for ABC. The median length of radiographic follow-up was 19.5 mo.

RESULTS

All ABCs except one (96%) showed healing or stable disease after a median of 4 (range 1-8) injections. Complete clinical and radiographic healing was observed in 16 cysts (70%), while partial radiographic healing with resolution of pain was seen in 6 cases (26%) and considered as stable disease. The cyst that failed to heal had previously undergone curettage twice with recurrence. One patient with a large pelvic ABC experienced, right after two injections, a sudden drop in blood pressure, which could quickly be reversed. One patient with a juxtaphyseal ABC in the femoral neck showed a minor limb length discrepancy because of deformity. Beyond that, no complications were observed.

CONCLUSION

Percutaneous sclerotherapy with polidocanol appears to be a safe alternative for treatment of aneurysmal bone cysts. In our series of both primary and recurrent cysts, it showed the ability to achieve healing or stable disease in 22 of 23 cases (96%). Further studies are needed to decide if this provides a long-lasting effect.

Aneurysmal bone cyst of the clavicle: A case report

INTRODUCTION

An aneurysmal bone cyst (ABC) is a locally aggressive primary bone neoplasm. ABC of the clavicle is rare with only a few reported cases in the literature.

PRESENTATION OF CASE

We report the case of a 10-year-old boy who presented with an ABC at the right acromial end of the clavicle. The patient underwent intralesional curettage and allogenic bone grafting. Moreover, the patient's arm was placed in a sling for 2 weeks postoperatively. The patient had a satisfactory outcome after 11 years, with excellent Toronto Extremity Salvage, Quick-Dash, and Musculoskeletal Tumor Society scores.

DISCUSSION

Clavicular ABCs are uncommon. Early diagnosis helps to prevent pathological fractures. Adjuvant therapies might help decrease recurrence.

CONCLUSION

ABC should be considered an important differential diagnosis for clavicular swelling and masses. The best results can be achieved using curettage and void-filled bone grafts.

LEVEL OF EVIDENCE: 4

Successful treatment of a benign, non-infected cyst in a dog by bone marrow injections

Bone cysts are rare orthopaedic problems in dogs. There are no clear treatment guidelines. A young male Shih Tzu was referred to Small Animal Clinic with fifth-degree lameness (5/5) of the left thoracic limb, and with swelling and deformation of the distal humeral region. The radiological assessment revealed an enlargement of the distal brachium and an extensive hypodense osteolytic lesion in the distal metaphyseal region of the humerus. Diagnosis of the bone cyst was formulated and treated with a mini-invasive method using autologous non-concentrated bone marrow injections. The treatment was successful, and at the three weeks, the cyst significantly changed its structure. The follow-up at 12 weeks after the first injection, and at one year revealed complete recovery. To our knowledge, this is the first evidence of a bone cyst in a young dog successfully treated with a minimally-invasive method by using a non-concentrated autologous bone marrow injection.

Imaging of Common and Infrequent Extradural Tumors

Spinal extradural tumors, although uncommon, have high morbidity and mortality rates. Radiographs and computed tomography scans are typically used to assess and determine the characteristics of these tumors. However, MR imaging is the preferred method for the evaluation of complications that can increase morbidity, such as spinal cord and nerve compression. Imaging features, such as type of matrix, cortical involvement, and margins, aid in determining the diagnosis. This article discusses common and infrequent extradural spinal tumors, their imaging characteristics, and how age, location, and clinical presentation help in diagnosing these neoplasms.

Primary Benign Neoplasms of the Spine

Benign tumours comprise the majority of primary vertebral tumours, and these are often found incidentally on imaging. Nonetheless, accurate diagnosis of these benign lesions is crucial, in order to avoid misdiagnosis as more ominous malignant lesions or infection. Furthermore, some of these tumours, despite their benign nature, can have localised effects on the spine including neural compromise, or can be locally aggressive, thus necessitating active management. Haemangiomas and osteomas (enostosis) are the commonest benign tumours encountered. Others include osteoid osteoma, osteoblastoma, fibrous dysplasia, osteochondroma, chondroblastoma, haemangioma, simple bone cysts, aneurysmal bone cysts, giant cell tumours, eosinophilic granuloma and notochordal rests. The majority of lesions are asymptomatic; however, locally aggressive lesions (such as aneurysmal bone cysts or giant cell tumours) can present with nonspecific symptoms, such as back pain, neurological deficits and spinal instability, which may be indistinguishable from more commonly encountered mechanical back pain or malignant lesions including metastases. Hence, imaging, including radiography, computed tomography (CT) and magnetic resonance imaging (MRI), plays a critical role in diagnosis. Generally, most incidental or asymptomatic regions are conservatively managed or may not require any follow-up, while symptomatic or locally aggressive lesions warrant active interventions, which include surgical resection or percutaneous treatment techniques. Due to advances in interventional radiology techniques in recent years, percutaneous minimally invasive techniques such as radiofrequency ablation, sclerotherapy and cryoablation have played an increasing role in the management of these tumours with favourable outcomes. The different types of primary benign vertebral tumours will be discussed in this article with an emphasis on pertinent imaging features.

Single dose intralesional doxycycline foam infusion promotes bone growth and resolution of an odontoid aneurysmal bone cyst

Background

Aneurysmal bone cysts (ABCs) are locally invasive bone tumors that most commonly arise in long bone metaphyses, the vertebral column, and pelvis, often presenting in the second decade of life. ABCs can be treated with resection, radiation, arterial embolization, and intralesional curettage. More recently intralesional doxycycline foam injections, which appear to act through the inhibition of matrix metalloproteinases and angiogenesis, have been used successfully, although multiple treatments are often required with this approach.

Case Description

A 13-year-old male with an incidentally discovered ABC filling much of the odontoid process but not violating the native odontoid cortex was treated with a single intralesional doxycycline foam injection delivered through a transoral approach with an excellent radiographic result. After placing a Crowe-Davis retractor, a transoral exposure of the odontoid process was performed with neuronavigation guidance. A fluoroscopy-guided Jamshidi needle biopsy was performed and via the needle doxycycline foam (2 mL 50 mg/mL doxycycline, 2 mL 25% albumin, and 1 mL Isovue 370 mixed with 5 mL of air) was infused, filling the cystic cavities of the odontoid process. The patient tolerated the operation well. Two months postoperatively, a computed tomography (CT) scan demonstrated a decrease in the size of the lesion with substantial new bone formation. Repeat CT at 6 months showed no residual cystic lucency, formation of dense new bone, and only minimal irregularity of the cortex at the prior needle biopsy site.

Conclusion

This case illustrates that the use of doxycycline foam can be an excellent option when managing ABCs that cannot be resected without incurring significant morbidity.

Allograft Versus Bioactive Glass (BG-S53P4) in Pediatric Benign Bone Lesions: A Randomized Clinical Trial

BACKGROUND

Benign bone cysts in children have a high risk of recurrence after bone grafting. The optimal treatment and filling material for these lesions are currently unknown.

METHODS

We compared cyst recurrence after intralesional curettage and filling with allograft versus bioactive glass (BG-S53P4; Bonalive) in a randomized clinical trial. The volume of recurrent cyst at 2-year follow-up was the primary outcome.

RESULTS

Of 64 eligible children, 51 (mean age, 11.1 years) were randomized to undergo filling of the cyst using morselized allograft (26) or bioactive glass (25). Twelve (46%) of the children in the allograft group and 10 (40%) in the bioactive glass group developed a recurrence (odds ratio [OR] for bioactive glass = 0.79, 95% confidence interval [CI] = 0.25 to 2.56, p = 0.77). The size of the recurrent cyst did not differ between the allograft group (mean, 3.3 mL; range, 0 to 13.2 mL) and the bioactive glass group (mean, 2.2 mL; range, 0 to 16.6 mL, p = 0.43). After adjusting for the type of lesion (aneurysmal bone cyst versus other), bioactive glass also did not prevent larger (>1 mL) recurrent cysts (adjusted OR = 0.42, 95% CI = 0.13 to 1.40, p = 0.16). The Musculoskeletal Tumor Society score improved significantly (p ≤ 0.013) from preoperatively to the 2-year follow-up in both groups (to 28.7 for bioactive glass and 29.1 for bone graft). Four (15%) of the children in the allograft group and 6 (24%) in the bioactive glass group required a reoperation during the follow-up (OR for bioactive glass = 1.74, 95% CI = 0.43 to 7.09, p = 0.50).

CONCLUSIONS

Filling with bioactive glass and with allograft in the treatment of benign bone lesions provided comparable results in terms of recurrence and complications.

LEVEL OF EVIDENCE

Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Giant cell tumor of bone with secondary aneurysmal bone cyst does not have a higher risk of local recurrence

BACKGROUND

Fluid-fluid levels (FFLs) is found in 10%-16% of giant cell tumor of bone (GCTB), and the presence of FFLs raises the suspicion of GCTB with secondary aneurysmal bone cyst (ABC), which can lead to increased intraoperative bleeding and, blurring the operative field, be associated with a risk of local recurrence. The first objective of this study is to determine whether secondary ABC is associated with a higher risk of local recurrence after curettage in patients with GCTB of the extremities. The second objective of this study is to investigate the sensitivity, specificity, positive predictive value, and negative predictive value of the presence of FFLs detected on magnetic resonance imaging (MRI) to diagnose secondary ABC associated with GCTB.

METHODS

Two hundred and eighty patients with GCTB of the extremities who underwent curettage at the authors' institutions between 1980 and 2021 were included in this study.

RESULTS

Secondary ABC was found in 36 of 280 patients (12.9%) and local recurrence occurred in 66 of 280 patients (23.6%). Multivariate analysis showed no significant correlation between secondary ABC and local recurrence (hazard ratio [HR]: 1.87 (95% confidence interval [CI]: 1.00-3.53]; p = 0.051). Preoperative MRI revealed FFLs in 13 of 82 patients (15.9%). Sensitivity, specificity, positive predictive value, and negative predictive value of FFLs detected on preoperative MRI to diagnose secondary ABC were 36.8%, 90.5%, 53.8%, and 82.6%, respectively.

CONCLUSION

The results of this study showed that secondary ABC does not increase the risk of local recurrence after curettage in patients with GCTB of the extremities. Although rare, FFLs were present in patients with GCTB and half of those with FFLs detected on preoperative MRI had secondary ABC.

Aneurysmal bone cyst of the temporal bone presenting with reversible vestibular impairment

BACKGROUND

Aneurysmal bone cysts are expansile benign lesions associated with compressive destruction and obscure pathogenesis. The most common sites of temporal bone involvement are the petrous apex, squamous portions and mastoid.

CASE REPORT

This paper reports a right temporal aneurysmal bone cyst in a 51-year-old man who presented clinically with facial palsy, and hearing loss and impaired vestibular function. Magnetic resonance imaging and computed tomography findings were consistent with a diagnosis of aneurysmal bone cyst. Inter-operative findings showed that the lesion had caused compressive damage to the internal auditory canal. Following surgical excision, the patient experienced vertigo, indicating recovery of vestibular function. Follow-up imaging revealed complete resection without clinical recurrence.

CONCLUSION

To our knowledge, this is the first report of aneurysmal bone cyst invasion of the inner auditory canal. Our clinical experience indicates that vestibular nerve damage recovery is relatively uncommon. This case report will hopefully inform future studies.

A Rare Case of Trigeminal Neuralgia Caused by an Aneurysmal Bone Cyst in the Temporal Bone

Trigeminal neuralgia is a rare and debilitating condition characterized by severe facial pain, often caused by the compression or irritation of the trigeminal nerve. Although trigeminal neuralgia caused by petrous bone lesions is uncommon, it can significantly impact a patient's quality of life. In this case report, we describe a 40-year-old female with a five-year history of severe facial pain diagnosed as trigeminal neuralgia. Imaging revealed an aneurysmal bone cyst in the petrous part of the left temporal bone, located near the trigeminal nerve's root entry zone. The patient underwent a successful left retrosigmoid craniotomy with the resection of the lesion, resulting in a significant improvement in her symptoms. At the six-month follow-up, the patient reported no recurrence of her symptoms and a considerable improvement in her quality of life. Although trigeminal neuralgia caused by an aneurysmal bone cyst in the left temporal bone is rare, surgery is the most effective treatment. Long-term outcomes are generally favorable with close follow-up. This case report highlights the importance of early diagnosis and timely surgical intervention in the management of this debilitating condition.

MR angiography facilitates the differentiation of aneurysmal from unicameral bone cysts

OBJECTIVES

The objective of this work was to evaluate the incremental value of MR angiography over plain radiographs and MRI for the differentiation of aneurysmal bone cysts (ABCs) from unicameral bone cysts (UBCs).

METHODS

Thirty-six juvenile patients with histologically secured primary ABCs or UBCs were included in this retrospective study. Two radiologists assessed all obtained images in a blinded fashion using a catalog of previously suggested imaging findings. A second readout with supplementary MR angiography images was performed after 8 weeks to prevent observer recall bias. Diagnostic accuracy parameters were calculated for individual imaging findings, and overall diagnostic accuracy and diagnostic confidence were assessed for all readouts. Receiver operating characteristic (ROC) curve comparison was used to determine the incremental value of MR angiography.

RESULTS

Of 16 imaging features, only abnormal vascularization in MR angiography provided sufficient diagnostic accuracy for the identification of ABCs. Other imaging features such as fluid-fluid levels and internal septations were insufficient for the differentiation of UBCs from ABCs. Availability of MR angiography images significantly increased diagnostic accuracy (94.4 vs 75.0% and 83.3 vs 69.4%, respectively, p < 0.05) and diagnostic confidence (4.5 vs 3.7, p < 0.05) of reading radiologists.

CONCLUSION

The presence of arterial feeders in MR angiography can accurately discriminate primary ABCs from UBCs and increases the diagnostic accuracy and diagnostic confidence of reporting radiologists.

ADVANCES IN KNOWLEDGE

Radiographic differentiation of cystic bone lesions such as ABCs and UBCs remains challenging. We demonstrate that MR angiography provides incremental value and suggest inclusion in standard examination protocols.

Aneurysmal bone cyst: a review

Aneurysmal bone cyst (ABC) is a benign locally destructive bone neoplasm composed of multi-loculated blood-filled cystic spaces. The most common sites of involvement are the meta-diaphysis of the long bones and posterior elements of the vertebrae. Secondary, ABC-like changes can complicate a variety of other benign and malignant primary bone neoplasms, including giant cell tumor, fibrous dysplasia, and osteosarcoma. About two-third of primary ABCs have a rearrangement of the USP6 gene, which is not present in the ABC-like changes that occur secondary to other primary bone tumors (i.e., secondary ABC). Primary ABC of bone carries a variable but generally high rate of local recurrence. This paper provides an overview of the pathophysiology, clinical presentation, radiographic and pathologic findings, treatment, and prognosis of ABC.

Pseudocysts of the jaw: a retrospective study of 41 cases from a single institution

OBJECTIVE

The purpose of this retrospective study was to investigate and compare the clinical, radiographic, pathological, pathogenesis, and therapeutic features of simple bone cysts (SBCs) and aneurysmal bone cysts (ABCs) of the jaw.

METHODS

35 patients with SBCs and 6 patients with ABCs who received treatment at the Department of Oral and Maxillofacial Surgery, Zhejiang University School of Medicine from 2017 to 2022 were followed up and reviewed retrospectively.

RESULTS

The study included 41 patients, accounting for 2.14% of all jaw pathologies, with 35 patients having SBCs and 6 patients having ABCs; their average ages were 26.63 ± 13.62 years and 17.83 ± 7.88 years, respectively. The prevalence of SBC and ABC did not differ significantly by sex. The mandible was the most vulnerable area to be involved. Only 5.71% (2/35) of patients with SBCs and 16.7% (1/6) of patients with ABCs reported histories of previous trauma in the same region of the pseudocysts. A total of 42.86% (15/35) of SBC cases and 66.67% (4/6) of ABC cases had malocclusions. The radiographic features of pseudocysts varied in shape, were associated with the root, and unilocular or multilocular. All patients had curettage with or without bone graft or substitute implantation, and recurrences did not occur in 94.29% (33/35) of SBC patients and 100% (6/6) of ABC patients after a mean follow-up time of 26.23 ± 15.47 months and 21.67 ± 19.75 months, respectively.

CONCLUSIONS

Pseudocysts, including SBCs and ABCs, are benign osteolytic lesions without an epithelial lining that occur occasionally in the jaw, mostly in adolescents and young adults, and their incidence did not significantly differ by sex. The most vulnerable site of involvement is the mandible, and they are generally not overtly aggressive. Trauma has a less significant role in pseudocysts, but minor trauma, such as malocclusion, has the potential to influence pseudocyst development. The clinical presentation of pseudocysts lacks specificity, and most patients are asymptomatic and found incidentally during radiographs. Dental panoramic radiographs and CBCT cannot accurately distinguish between SBC and ABC, and the final diagnosis depends on pathological diagnosis. Curettage combined with bone grafting is currently the best treatment for both, with a 5.71% (2/35) recurrence rate for SBC and no recurrence found for ABC.

Finite Element Analysis of Mechanical Characteristics of Internal Fixation for Treatment of Proximal Femoral Osteolytic Lesions in Children

OBJECTIVES

Clinically, it is very difficult to prevent pathological fracture caused by high recurrence rate of osteolytic disease of proximal femur in children. At present, there is no consensus in clinical studies of which internal fixation method can significantly reduce the probability of recurrence of pathological fracture. The study aims to research the mechanical properties of different internal fixations in the treatment of osteolytic lesions of proximal femur in children by finite element analysis, and to find out the optimal treatment.

METHODS

Based on finite element analysis, the osteolytic disease models of the femoral neck and intertrochanter in a child (8-year-old, boy) were established respectively, and different internal fixation models (plate and titanium elastic intramedullary nails, TENs) were assembled. For the osteolytic lesion of the femoral neck: model A1 was assembled with a plate; model A2 with two TENs crossing the physis; model A3 with two TENs without crossing the physis. And for pertrochanteric osteolytic lesion: model B1 was assembled with a plate, model B2 with two TENs crossing the physis and model B3 with two TENs without crossing the physis. The Eccentric bearing load, torsional restraintal restraint of calcar femorale and composite load were analyzed for each models.

RESULTS

When the yield strain of each model is reached, the stress concentration points are located in the proximal and distal femoral calcar. In the model of femoral neck lesions, the failure load of model A1 and model A2 are the same (1250 N), and the failure load of model A3 (980 N) is significantly lower than that of the former two; in the model of intertrochanteric lesions, the failure load of model B2 is the largest (1350 N), and the failure load of model B1 (1220 N) is lower than that of model B3 (1260 N), but both are smaller than that of model B2.

CONCLUSION

Through finite element analysis, TENs through the epiphyseal plate, is found to be the better internal fixation method for femoral neck lesions and intertrochanteric lesions under two different working conditions. The results of clinical correlation study provide new biomechanical information for orthopedic doctors to consider different treatment options for osteolytic lesions of proximal femur.

Do's and Don'ts in Primary Aneurysmal Bone Cysts of the Proximal Femur in Children and Adolescents: Retrospective Multicenter EPOS Study of 79 Patients

BACKGROUND

Aneurysmal bone cysts (ABC) are rare benign cystic bone tumors, generally diagnosed in children and adolescents. Proximal femoral ABCs may require specific treatment strategies because of an increased pathologic fracture risk. As few reports are published on ABCs, specifically for this localization, consensus regarding optimal treatment is lacking. We present a large retrospective study on the treatment of pediatric proximal femoral ABCs.

METHODS

All eligible pediatric patients with proximal femoral ABC were included, from 11 tertiary referral centers for musculo-skeletal oncology (2000-2021). Patient demographics, diagnostics, treatments, and complications were evaluated. Index procedures were categorized as percutaneous/open procedures and osteosynthesis alone. Primary outcomes were: time until full weight-bearing and failure-free survival. Failure was defined as open procedure after primary surgery, >3 percutaneous procedures, recurrence, and/or fracture. Risk factors for failure were evaluated.

RESULTS

Seventy-nine patients with ABC were included [mean age, 10.2 (±SD4.0) y, n=56 male]. The median follow-up was 5.1 years (interquartile ranges=2.5 to 8.8).Index procedure was percutaneous procedure (n=22), open procedure (n=35), or osteosynthesis alone (n=22). The median time until full weight-bearing was 13 weeks [95% confidence interval (CI)=7.9-18.1] for open procedures, 9 weeks (95% CI=1.4-16.6) for percutaneous, and 6 weeks (95% CI=4.3-7.7) for osteosynthesis alone ( P =0.1). Failure rates were 41%, 43%, and 36%, respectively. Overall, 2 and 5-year failure-free survival was 69.6% (95% CI=59.2-80.0) and 54.5% (95% CI=41.6-67.4), respectively. Risk factors associated with failure were age younger than 10 years [hazard ratios (HR)=2.9, 95% CI=1.4-5.8], cyst volume >55 cm 3 (HR=1.7, 95% CI=0.8-2.5), and fracture at diagnosis (HR=1.4, 95% CI=0.7-3.3).

CONCLUSIONS

As both open and percutaneous procedures along with osteosynthesis alone seem viable treatment options in this weight-bearing location, optimal treatment for proximal femoral ABCs remains unclear. The aim of the treatment was to achieve local cyst control while minimizing complications and ensuring that children can continue their normal activities as soon as possible. A personalized balance should be maintained between undertreatment, with potentially higher risks of pathologic fractures, prolonged periods of partial weight-bearing, or recurrences, versus overtreatment with large surgical procedures, and associated risks.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

A Review of Pediatric Heel Pain

The objective of this review article is to provide orthopaedic surgeons and general practitioners a reference and guidance for the evaluation and workup of heel pain in pediatric patients. The authors performed a comprehensive literature search to review the etiologies and management of heel pain in patients <18 years of age. Relevant studies in Medline/PubMed and EMBASE were searched from inception to March 3, 2022 using medical subject headings and text words without limitations on language or study type. The initial search utilized the following Boolean operators: (children) AND (heel pain); (pediatric) AND (heel pain). Heel pain in the pediatric population is usually a benign condition. Sever's apophysitis is the most common etiology of heel pain in pediatric patients. Most causes of heel pain in the pediatric population do not require imaging or extensive workup. However, providers must maintain a high index of suspicion for symptoms that could indicate a more severe pathology.

Compound Heterogeneous Sickle Cell-B+ Thalassemia Incidentally Discovered Through Cytological Examination of a Fine-Needle Aspiration Specimen from an Aneurysmal Bone Cyst in a Young Child: A Case Report

Sickle cell beta-thalassemia (S/β) is a rare inherited variant of sickling disorders, usually occurring due to the inheritance of two abnormal genes, namely, the sickle cell gene, and the beta-thalassemia gene. There are two types of sickle cell β-thalassemia: (S/β+) and (S/β0), based on a decrease or complete absence of beta-globin synthesis, respectively. Skeletal complications, such as osteonecrosis, osteomyelitis, and septic arthritis, are well-known sequelae in sickle cell patients due to vaso-occlusive events. Nevertheless, the occurrence of aneurysmal bone cysts in patients with sickle cell hemoglobinopathy is an exceptional phenomenon. Herein, we report a case of a young boy who presented with nonspecific clinical symptoms over a few years. The patient was referred to our institution as a case of short stature with recurrent joint pain. A clinical workup was done and an aneurysmal bone cyst (ABC) of the left humerus was discovered radiologically with incidental detection of sickle cells through cytological evaluation of the cyst fluid. Further clinical investigation, including molecular and additional laboratory tests, confirmed the diagnosis of compound heterogeneous sickle cell-B+ thalassemia. Unfortunately, neither was the underlying pathology detected nor was the precise clinical diagnosis attained at the outside primary healthcare facility.

Stabilisation of Pathologic Proximal Femoral Fracture near the Growth Plate with Use of a Locking Plate and Transphyseal Screws

Aneurysmal bone cyst (ABC) is a benign osseus lesion with a high pathologic fracture risk. The described treatment options are varied and inconsistent. For successful treatment results, it is essential to prevent recurrence and sufficiently stabilise the weakened bone. Lesions close to the growth plates, especially in the femoral neck region, are challenging to stabilise in children. In this study, 27 clinics, including 11 sarcoma centres, 15 paediatric orthopaedic clinics, and one sarcoma/paediatric orthopaedic centre, were surveyed and asked about their treatment approaches for an exemplary case of ABC in the femoral neck causing a pathological fracture in a 20-month-old infant, with a response rate of 81%. The heterogeneity of treatment options described in the literature is consistent with the survey results. The most favoured approach was curettage, defect filling of any kind, and surgical stabilisation. However, the lesion stabilisation option introduced in this paper, which involves the use of transphyseal screws, was not mentioned in the survey and has not been reported in the literature. Contrary to the existing concepts, our technique offers high stability without significant growth restriction. Transphyseal screws are also suitable for the treatment of femoral neck fractures of other aetiologies in children.

Giant aneurysmal bone cyst of the scapula: A case report

Aneurysmal bone cyst (ABC) is a benign bone tumor affecting mainly children and young adults. It occurs in the metaphysis of the long bones. The scapula is a very rare location. Imaging may be highly suggestive of ABC in cases of an osteolytic, expansive, and hemorrhagic lesion with fluid-fluid levels and thin septa. The diagnosis must systematically be confirmed by performing a biopsy, in order to adopt the best therapeutic strategy. There are several therapeutic means, but wide resection remains the gold standard. The evolution is very variable and can go from spontaneous healing to recurrence with the destruction of the bone. We report a rare case of aneurysmal bone cyst of the scapula in a young patient.

Treatment of Aneurysmal Bone Cysts by Minimally Invasive Curettage and Allogenic Bone Impaction Grafting: Mid-to Long-term Results

OBJECTIVE

Recurrence is the main hinderance in treatment of aneurysmal bone cysts (ABCs). Therefore, several treatment modalities and adjuvant therapies have been proposed. In this study, we aim to evaluate the long-term effectiveness of percutaneous curettage and allogenic bone grafting as a new, minimally invasive modality in treating ABCs.

METHODS

We performed a retrospective review of the medical records of patients diagnosed with primary ABCs at a university hospital over a 10-year period (2000-2010). We selected all patients who were diagnosed with primary ABC in the extremities and pelvis, treated with the same surgical procedure, and were followed for at least 2 years postoperatively. All patients underwent the same procedure of percutaneous curettage and impaction of allogenic pulverized fine bone fragments (harvested from locally stored femoral heads) mixed with autologous bone marrow aspirate from the iliac bone. We reported patient's characteristics (age and gender), site and size of the lesion, presenting symptoms, Capanna classification, follow-up duration, and post-operative complications. Assessment of cyst healing was based on the appearance on radiographs according to the modified Neer classification.

RESULTS

Nineteen patients were included in this study; 10 patients were males and nine were females. The mean age was 9.6 years (range 3-15). The location of the lesions was as follows: femur (eight), tibia (four), pelvis (four), proximal humerus (one), distal radius (one), and calcaneus (one). The most common presenting symptom was pain in the involved area. Pathological fracture was the presenting feature in two patients. The mean follow-up duration was 6.4 years (range 2-18). The earliest radiological sign of incorporation of the allograft was seen at 3 months after surgery. All patients showed bone remodeling and radiographic resolution (classified as either A or B on the modified Neer classification) of their cystic lesions within 6 months. No local recurrence, infection, or pathological fractures occurred during the follow-up period.

CONCLUSION

Percutaneous curettage and impaction of allogenic bone graft mixed with autogenic bone marrow aspirate is an efficient, minimally invasive, reproducible, and affordable procedure for the treatment of primary ABCs.

Percutaneous image-guided treatment of aneurysmal bone cysts: is there a superior treatment option?

BACKGROUND

Aneurysmal bone cysts (ABCs) are often treated with intralesional surgery (curettage) with or without adjuvant treatments. Side effects and conflicting results regarding recurrence rates do not suggest one clearly superior therapy. Percutaneous therapeutic options including sclerotherapy and thermal ablation have gained popularity as potential alternatives.

OBJECTIVE

The purpose of this retrospective review is to report this institution's experience and results of various image-guided minimally invasive treatments in a single institution series of cases referred to interventional radiology by orthopedic surgery after surgical failure or in patients with anatomically challenging ABCs.

MATERIALS AND METHODS

This study identified all patients ≤18 years old who received percutaneous therapy for an ABC, including cryoablation, doxycycline sclerotherapy, microwave ablation or a combination of these modalities. Procedural details, complications, imaging follow-up and clinical follow-up were analyzed.

RESULTS

A total of 21 patients received 41 procedures, with major complications seen in 7.7% (3/39) of procedures involving cryoablation or doxycycline sclerotherapy. Patients receiving cryoablation required an average of 1.7 procedures (median: 1 procedure, range: 1-4 procedures) while patients receiving doxycycline sclerotherapy required an average of 3 procedures (median: 2 procedures, range: 1-6 procedures). Patients were followed clinically and with computed tomography or magnetic resonance imaging (average: 23.9 months, range: 3.9-68.3 months). Follow-up imaging demonstrated improvement in 17 (85%) patients. Clinically, 93.8% (15/16) of patients who presented with fracture or pain had markedly reduced or absent pain as well as no fractures.

CONCLUSION

Percutaneous image-guided treatment of ABCs demonstrates a favorable efficacy and safety profile. Adding cryoablation may lead to fewer total procedures than using doxycycline sclerotherapy alone.

Percutaneous doxycycline sclerotherapy in a horse with a mandibular aneurysmal bone cyst

OBJECTIVE

To describe the use and outcome of sclerotherapy with intralesional doxycycline foam in a horse with a mandibular aneurysmal bone cyst.

STUDY DESIGN

Case report.

ANIMALS

Client-owned 1 year old Standardbred filly.

METHODS

The horse presented for progressive mandibular swelling. A 10 mg/mL doxycycline foam was prepared for intralesional injection. Three doses were injected into the lesion under computed tomographic guidance at 6 and 15 weeks after initial treatment. Volume reduction was monitored after each treatment with 3D volumetric rendering and region of interest segmentation using commercially available software.

RESULTS

The volume of the lesion decreased from 458.7455 cm³ before treatment, to 363.3101 cm³ at 6 weeks, 273.5855 cm³ at 15 weeks, and 247.2316 cm³ 6 months later, resulting in a total reduction of 54% of the initial volume. Bone formation was noted in the lesion. No adverse effects related to doxycycline foam injections were noted. The mandibular swelling was resolved after treatment.

CONCLUSION

Intralesional doxycycline sclerotherapy was shown to be efficacious in reducing the volume of the aneurysmal bone cyst in the horse presented in this report. There was complete resolution of mandibular swelling with no side effects related to the intralesional injections.

Results in the surgical treatment of aneurysmal bone cysts - A retrospective data analysis

BACKGROUND

Aneurysmal bone cysts (ABC) are benign tumors mostly occurring in children and young adults. Different open and minimal invasive surgical approaches have been proposed for the treatment of ABCs and yet no consensus is defined to date. The aim of this study was to retrospectively review data of a large single center series of ABCs with patients treated by open curettage with or without filling of the cavity or en-bloc resection. Questions/purposes We asked: (1) What was the local recurrence rate of ABC after surgical treatment at our institution? (2) What were positive or negative predictors for local recurrence? (3) Was there a benefit from adjuvant burring, phenolization or filling, respectively? (4) Where there changes in recurrence free survival in different time periods of primary surgery?

METHODS

By retrospective data analysis of the Vienna Bone and Soft Tissue Tumor Registry, 123 patients surgically treated for primary aneurysmal bone cysts were identified. After exclusion of 33 patients (27%) due to a postoperative follow up below one year, 90 patients who were treated for primary ABCs between 1986 and 2009 were evaluated. These included 50 males and 40 females with a mean age of 16 years (SD 10 years; range: 2 to 51 years). The mean follow-up was 99 months. (SD 72 months, range: 13 to 329 months) RESULTS: Curettage was performed in 84 patients, while 45 patients received adjuvant phenolization. Local recurrence occurred in 28 patients after a mean time of 16 months, with a corresponding local recurrence free survival (RFS) of 83% after one year, 77% after 2 years and 66% after 5 years. ABCs located in hands and feet (p=0.044) showed a superior RFS, while younger patients (p=0.001) displayed an inferior RFS. Regarding adjuvant surgical techniques, mechanical cavity burring (p=0.004) and filling with autologous cancellous bone graft (p=0.024) showed protective effects on RFS. Patients treated between 1986 and 1999 (n=47) had a higher RFS than patients treated between 2000 and 2009 (n=43, p=0.011), as surgeons and surgical indications changed over time.

CONCLUSION

Although curettage, burring, phenolization and reconstruction with bone grafts came with a relatively high risk of local recurrence, open surgery is still justified in aggressively growing ABCs of critical localizations.

LEVEL OF EVIDENCE

IV; therapeutic study.

Benign bony tumors of the paranasal sinuses, orbit, and skull base

Benign bony tumors of the skull base and paranasal sinuses are uncommon entities, with an overall higher incidence in males. Benign bony tumors may lead to local expansion with resultant mass effect of potentially critical structures. Some benign bony tumors may undergo malignant transformation. This article reviews the presentation and management of benign bone tumors of the skull base and paranasal sinuses with special consideration to involvement of the adjacent orbit, intracranial and critical neurovascular structures. This review covers tumor incidence, location, gross and histologic appearance as well as radiographic findings, treatment, and recurrence rates. Tumors discussed in this article include osteochondromas, osteomas, osteoid osteomas, aneurysmal bone cysts, fibrous dysplasia, giant cell tumors, cemento-ossifying fibroma, ameloblastic fibro-odontoma, ecchordosis physaliphora, chondromyxoid fibroma, primary chronic osteomyelitis, primary chronic osteomyelitis, osteochondromyxoma, and dense bone islands.

Aneurysmal bone cyst and osteoblastoma after neoadjuvant denosumab: histologic spectrum and potential diagnostic pitfalls

The use of denosumab to treat giant cell tumors of bone (GCT) and other giant cell-containing bone tumors has become more common. While the clinicopathologic features of denosumab-treated giant cell tumors of bone have been well-illustrated, descriptions of other denosumab-treated bone tumors are very limited. Surgical pathology files of two institutions and consultation files from two authors were searched for denosumab-treated aneurysmal bone cysts and denosumab-treated osteoblastomas. Clinicopathologic features were reviewed and analyzed. We identified four patients with denosumab-treated bone tumors other than GCT from our surgical pathology and consultation files, including two aneurysmal bone cysts and two osteoblastomas. All were treated with denosumab for 0.5-7.0 (median 4.5) months. Radiologically, denosumab-treated tumors showed decreased size with increased ossification and mineralization on CT and heterogeneous intermediate to hypointense signal on MRI. Histologically, denosumab-treated aneurysmal bone cyst contained thin, elongated, curvilinear, and anastomosing strands of bone with empty lacunae, while denosumab-treated osteoblastoma showed circumscribed nodules of woven bone lined by small osteoblasts. Denosumab-treated aneurysmal bone cyst and osteoblastoma showed treatment-related morphologic changes that can mimic other bone neoplasms. Their recognition requires correlation with the clinical history of denosumab use and radiologic findings.

Surgical treatment of benign lesions and pathologic fractures of the proximal femur in children

PURPOSE

Benign lesions of the proximal femur region, such as simple bone cysts, aneurysmal bone cysts, and fibrous dysplasia, are common in children. Benign lesions may cause pathologic fractures, limb length inequities, and growth disturbances. Differential diagnoses, e.g., malignant bone tumors and osteomyelitis, are sometimes difficult to rule out.

OBJECTIVE

We aimed to evaluate outcomes in children with benign lesions of the proximal femur treated with curettage, bone grafting, and plate fixation.

METHODS

In this retrospective study, we included 30 children (median age 10.5 years; range 1.1-17.8 years) suffering from bone cysts and tumor-like lesions of the proximal femur region treated between 2002 and 2018. We analyzed plain X-ray images and CT scans in all children and obtained MRI scans in a selected group of children (63.3%). We examined histopathologic biopsy results for all bone lesions before initiating treatment. Surgical management comprised tumor curettage with adjuvant high-speed drilling and allogenic bone grafting supplemented by bone graft substitutes before plate fixation. Median follow-up interval was 87 months (range 24-156 months). We evaluated the healing of lesions according to Capanna's classification and rated functional outcomes according to Merle d'Aubigné and Postel score.

RESULTS

Overall, 25 of 30 (83.3%) patients were admitted to hospital because of a pathologic fracture. We diagnosed simple bone cysts in 15 (50.0%) patients, aneurysmal bone cysts in 7 (23.5%) patients, and fibrous dysplasia in 8 (26.5%) patients. Bone consolidation was achieved in 22 of 30 (73.3%) patients after a mean of 5 months (range 3-7 months). The main complication was recurrence of the lesion in 4 of 30 (13.3%) patients. With respect to the Merle d'Aubigné and Postel scores, 17 of 30 (56.7%) patients obtained an excellent result (18 points), while 12 (40.0%) patients had a good result (15-17 points) and only 1 (3.3%) patient had a fair result (14 points).

CONCLUSION

Surgical treatment of bone cysts and tumor-like lesions of the proximal femur by local resection or destruction of the lesion, followed by filling the defect with bone graft material and internal stabilization represents a safe and effective treatment option in children.

LEVEL OF EVIDENCE

Therapeutic, retrospective comparative study-Level III.

Reverse shoulder megaprosthesis replacement for aggressive aneurysm bone cyst of proximal humerus: Case report and literature review

INTRODUCTION

and importance: Wide resection in the surgical treatment of aneurysms bone cysts is often performed in cases where the tumor is large, recurrent, growing, and intensely invasive. Reshaping the defect after tumor removal is a necessary issue to restore shape and maintain function for the patient.

CASE PRESENTATION

A 26-year-old male patient, diagnosed with an aneurysm bone cyst in the proximal humerus, underwent surgery for curettage and bone grafting twice. After surgery, there was still pain in the shoulder area, the tumor progressed aggressively with limited shoulder movement. Based on the imaging re-evaluation, it was shown that the tumor increased rapidly in size, invaded the soft tissue, and completely changed the normal structure of the shoulder joint, and the proximal humerus. We used a reverse shoulder joint with an additional module to restore the bone defect of the tumor and the function of the shoulder joint. Follows-up showed that patient no longer pain in shoulder area, shoulder joint function recovery is progressing well, Musculoskeletal Tumor Society (MSTS) score is 25 & 28, shoulder joint function score according to ASES scale: 80 & 93.33 respectively at 3 months and 6 months after surgery.

CLINICAL DISCUSSION

Aggresive aneurysm bone cyst of proximal humerus is not common and still a challenge to the treatment. Due to the bone and joint destruction, the indication of tumor resection and reconstruct the joint and bone loss is required. Among several solution, reverse shoulder megaprosthesis is a newest one can favor the purpose of our treatment. Up to now, this solution is mainly used to preserving for malignant bone tumor.

CONCLUSIONS

Tumor wide resection with modular reverse shoulder replacement with the modular segment is a reasonable intervention option in cases of large aneurysm bone cysts, with rapid recurrence, aggressive progression, and soft tissue invasion.

Autologous mesenchymal stem cells in the treatment of spinal aneurysmal bone cyst

PURPOSE

We retrospectively analyzed a cohort of patients treated at our Centre with bone marrow concentrated (BMC) injection for aneurysmal bone cyst (ABC) of the spine, in order to propose this treatment as a valid alternative for the management of ABCs.

METHODS

Fourteen patients (6 male, 8 female) were treated between June 2014 to December 2019 with BMC injection for ABC of the spine. The mean age was 15.5 years. The mean follow up was 37.4 months (range 12-60 months). The dimension of the cyst and the degree of ossification were measured by Computed Tomography (CT) scans before the treatment and during follow-up visits.

RESULTS

Six patients received a single dose of BMC, five patients received two doses and in three patients three doses of BMC were administered. The mean ossification of the cyst (expressed in Hounsfield units) increased statistically from 43.48 ± 2.36 HU to 161.71 ± 23.48 HU during follow-up time and the ossification was associated to an improvement of the clinical outcomes. The mean ossification over time was significantly higher in patients treated with a single injection compared to patients treated with multiple injections. No significant difference in ossification was found between cervical and non-cervical localization of the cyst. Moreover, the initial size of the cyst was not statistically associated with the degree of ossification during follow-up CONCLUSIONS: Results of this paper reinforce our previous evidence on the use of BMC as a valid alternative for spinal ABC management when SAE treatment is contraindicated or ineffective.