Percutaneous microwave ablation, perfusion, and reconstruction combined with a synthetic bone substitute in symptomatic bone cysts: a minimum of 26 months follow-up.

PURPOSE: The objective was to describe the technique and clinical outcome of microwave thermal ablation (MWA) and perfusion combined with synthetic bone substitutes in treating unicameral bone cysts (UBCs) in adolescents. MATERIALS AND METHODS: A total of 14 consecutive patients were enrolled by percutaneous MWA and saline irrigation combined with synthetic bone substitutes. Clinical follow-up included the assessment of pain, swelling, and functional mobility. Radiological parameters included tumor volume, physis-cyst distance, cortical thickness of the thinnest cortical bone, and the Modified Neer classification system. RESULTS: The mean follow-up was 28.9 months (26-52 months). All UBCs were primary, and all patients underwent the MWA, saline perfusion, and reconstruction combined with a synthetic bone substitute session, except for one patient (7.1%) who required a second session. All patients had good clinical results at the final follow-up. Satisfactory cyst healing was achieved in 13 cases according to radiological parameters. Tumor volume decreased from a mean of 49.7 cm3 before surgery treatment to 13.9 cm3 at the final follow-up (p < 0.01). The physis-cyst distance increased from a mean of 3.17-4.83 cm at the final follow-up (p < 0.01). Cortical thickness improved from a mean of 1.1 mm to 2.0 mm at the final follow-up (p < 0.01). According to the proposed radiological criteria, our results were considered successful (Grading I and II) in 13 patients (92.9%) at the final follow-up. CONCLUSION: Percutaneous microwave ablation combined with a bone graft substitute is a minimally invasive, effective, safe, and cost-effective approach to treating primary bone cysts in the limbs of adolescents.

Novel method to biopsy aneurysmal bone cysts in children.

PURPOSE: 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 AND MATERIALS: 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.

Aneurysmal bone cyst-like changes developed in melorheostosis with epiphyseal osteopoikilosis.

Aneurysmal bone cyst (ABC) is a rare and usually painful condition, representing about 1% of all bone tumors. A geographical lytic, expansile, and septated radiological pattern, with fluid-fluid levels on MRI, is classically displayed. ABC can be a primary bone lesion (70% of patients) or can arise in an underlying condition and is subsequently named "ABC-like changes" (30%). ABC-like changes are more frequently encountered in skeletal segments affected by chondroblastoma, fibrous dysplasia, giant cell tumor, osteoblastoma, non-ossifying fibroma, and osteosarcoma. In this article, we describe the first case of ABC-like changes developed in association with an ultra-rare sclerosing bone disease: melorheostosis. Melorheostosis is characterized by recognizable patterns on radiological studies with a pathological increased bone density and a cortical thickening within the periosteal or endosteal space, usually with a "dripping candle wax" appearance. More rarely, other different radiological patterns can be observed, such as "osteopatia striata-like," "osteoma-like," "myositis ossificans-like," and mixed patterns. Pain and limb hypotrophy are the most common clinical manifestations. We report the case of a Caucasian male with a clinic-radiological diagnosis of melorheostosis (with epiphyseal osteopoikilosis) since the age of twelve. At the age of nineteen, he suffered from increased pain in the proximal right thigh, and the radiological control revealed an expansive septated lesion at the right proximal femoral bone. The diagnosis of ABC-like changes developed in melorheostosis was obtained after CT-guided bone biopsy and confirmed by open-incisional biopsy.

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.

Structural features of subchondral bone cysts and adjacent tissues in hip osteoarthritis.

OBJECTIVE: Focal lesions within the subchondral bone, termed subchondral bone cysts (SBCs), are clinically accepted radiographic markers of advanced osteoarthritis (OA), but their etiology in the hip is not well understood. DESIGN: This study used micro-computed tomography (µCT), and histological and immunocytological analysis to examine the prevalence, size, location, and morphological and cellular features of SBCs found within 34 femoral heads (14 male, 20 female; age range = 43-80 years) obtained from total hip arthroplasty procedures. RESULTS: SBCs were common-present in 91% of the femoral heads examined-and frequently commuted with the surface of the femoral head, but otherwise showed no preferred anatomical location. Few associations were found between SBC features and patient characteristics such as BMI, age and sex. SBCs were also heterogenous in composition, ranging from fibrous (most common) to predominantly fatty (least common) and often containing vasculature, nerve fibers, cartilage islands, and bony spicules. Despite this heterogeneity, focal abnormalities in bone density and cartilage thickness were consistently observed. Bone adjacent to SBCs was denser than that in the primary compressive group, and cartilage thickness in regions overlying SBCs was lower than in non-overlying regions. In contrast to these local bony changes, µCT-based finite element analyses indicated that the stiffness of the primary compressive group was only mildly affected by SBCs. CONCLUSIONS: These findings indicate that SBCs in the femoral head involve extensive perturbations in cellular activity, culminating in myriad skeletal tissue types and spatially heterogenous changes in bone and cartilage morphology that are likely to affect OA progression.

MRI analysis of simple and aneurysmal bone cysts in the proximal humerus: what actually matters in clinical routine.

OBJECTIVE: To evaluate magnetic resonance imaging (MRI) characteristics of simple and aneurysmal bone cysts (SBC/ABC) of the proximal humerus and the intermittent difficulty in the imaging differentiation between the two in daily clinical routine. MATERIALS AND METHODS: MR images of 26 patients with suspected SBC/ABC in the proximal humerus were retrospectively assessed by two independent radiologists blinded to the final histological result. Based on a standard MRI protocol, different morphologic features and signal intensities of the lesion on non-enhanced and enhanced sequences were documented. The radiological diagnosis was correlated with histology. RESULTS: Eighteen patients had the image-based diagnosis of an SBC, yet the histology confirmed only 12, the residual 6 were identified as an ABC, despite the imaging criteria corresponding unambiguously to the former. One of the main reasons was the unicameral morphology of lesions, found in 9/14 (64.3%) cases of all ABCs, i.e., in 19/26 cases in total. Therefore, the sensitivity of the radiological diagnosis was moderate (57.14%), yet specificity very high (100%). In total, 69.2% (18/26) presented with a pathological fracture at admission, which correlated strongly with both circumferential (MCC = 0.65, p = 0.01) and septal (MCC = 0.42, p = 0.06) enhancement patterns. Circumferential enhancement was also found to correlate strongly with the histological diagnosis, being recognized in all cases of ABC (MCC = 0.44, p = 0.06). CONCLUSION: MRI characteristics of ABCs/SBCs in the proximal humerus are indifferent and ABCs may morphologically present as SBCs. Radiologists should be aware of the different, often confusing presentation of both entities in daily clinical routine.

Unusual magnetic resonance imaging findings of cystic bone lesions in congenital generalized lipodystrophy.

Cystic bone lesions are the hallmark of skeletal abnormalities in patients with congenital generalized lipodystrophy (CGL). However, their pathophysiology is still unclear and theories about their origin remain largely speculative. This article reports on a patient with CGL and cystic bone lesions, some of them with unusual magnetic resonance imaging (MRI) findings that include elevated signal intensity on T1-weighted images and fluid-fluid levels, the latter evolving to a more "classic" cystic appearance on follow-up. Even though similar findings were first described almost 30 years ago, little attention was given to them back then; furthermore, other than the present report, no other study has performed sequential exams to follow their evolution in serial MRI. The authors conduct a review of the literature, hypothesizing that these remarkable findings may reflect an intermediate stage in the process of cystification of the abnormal bone marrow, incapable to perform adipose conversion, lending factual support to the modern theories about this issue.

97 HINTEGRA ankle prostheses: Results and survival at more than 5 years' follow-up.

BACKGROUND: In Europe, fixed-bearing implants predominate again in total ankle replacement (TAR). The present single-center single-surgeon study assesses the Hintegra® mobile-bearing implant (NEWDEAL). METHODS: Between November 2008 and November 2015, 97 Hintegra® were implanted in 94 patients: mean age, 62.4±10.9 years (26-83); 59% (57/97) male; normal mean body-mass index (BMI), 27.5 ± 4.3 kg/m2. Indications mainly comprised posttraumatic (40.2%), instability (29.9%) and primary osteoarthritis (16.5%). 17.5% of patients had prior surgery during the previous 6 months (9 fusions, 8 ligament reconstructions, and 4 osteotomies); in 59.8%, other procedures were associated to TAR. Functional, clinical and radiological follow-up was conducted at 1 year, 2 years and last follow-up (>5 years). RESULTS: Ninety-four TARs were analyzed at a mean 81 ± 21.6 months (19-124). Revision-free survival was 76% (95% confidence interval (95%CI): 0.66-0.8), and explantation-free survival 92% (95%CI: 0.85-1) with 10 cases of curettage and 5 explantations. Mean AOFAS score improved from 41.8 ± 12.5 (21-69) to 77.5 ± 16.5 (24-100) up (p < 0.001); 75% of patients had no or only mild pain (p < 0.001). Clinical ranges of motion were 8.0 ± 7.1° dorsiflexion (p < 0.001) and 35.1 ± 9.4° plantar flexion (preoperatively, 34.1 ± 7.9°) (p = 0.71). Radiologically, tibial components were well-positioned; 87% of talar components were well-centered. Global ankle range of motion was 23.5 ± 10.2° (5-48) (p = 0.17). 54.6% of TARs showed posterior tibial calcification at follow-up. Risk of severe cyst (>1 cm) on CT was 36% (95%CI: 23-47) at a mean 77 ± 21.9 months (18-123). CONCLUSION: Hintegra® TAR incurred a low risk of revision, and is a reliable option for ankle osteoarthritis. LEVEL OF EVIDENCE: IV.

A comparison of depth of necrosis among adjuvant therapies used for the treatment of benign bone tumors.

BACKGROUND AND OBJECTIVES: Benign bone tumors are often treated with extended curettage utilizing an adjuvant therapy to eliminate any remaining tumor cells. The purpose of this study was to explore and compare the histologic depth of necrosis created by various adjuvant therapies used in the treatment of benign bone tumors. METHODS: A high-speed burr was utilized to create cortical defects within porcine humeri and femora. Phenol, polymethyl methacrylate (PMMA), argon beam coagulation (ABC), liquid nitrogen, and the Bipolar Hemostatic Sealer (BHS) were each applied to five defects, with an additional five defects left untreated as a control. The maximal depth of necrosis was determined under microscopic examination. RESULTS: The phenol, PMMA, ABC, liquid nitrogen, and BHS demonstrated an average histologic depth of necrosis of 0.30, 0.78, 2.54, 2.54, and 0.92 mm, respectively, each of which was significantly increased compared to the control group (p = .001, .003, .003, .01, and  <.001). Their respective variances, a measure of reproducibility, were 0.01, 0.09, 0.96, 1.93, and 0.03 mm2 . CONCLUSION: This study confirms, through histologic analysis, adjuvant therapies create a rim of cellular necrosis beyond that of burring during extended curettage, supporting their use in the treatment of benign bone tumors. Furthermore, it provides a head-to-head comparison.

Qualitative evaluation of MRI features in aneurysmal bone cysts after percutaneous sclerotherapy.

OBJECTIVE: To report MRI findings of changes seen in aneurysmal bone cysts after percutaneous sclerotherapy treatment. MATERIALS AND METHODS: After applying exclusion criteria, a total of 36 patients who had aneurysmal bone cysts and undergone percutaneous sclerotherapy were included in this study. The pre-treatment and post-treatment MRIs were reviewed and multiple pre-determined MRI findings were evaluated. The presence of each post-treatment finding, as well as the time for each finding to develop, was recorded. RESULTS: Early post-sclerotherapy changes include increased perilesional edema and enhancement, which appear on MRI on average 5.1 months after the initial sclerotherapy. This is followed by decreased cystic areas, which can be seen on average 5.9 months after the initial treatment. The presence of fibrosis, improved cortical integrity, and improving mass effect are later post-treatment changes and appear on MRI on average 9.7 months, 10.6 months, and 16.1 months after the initial sclerotherapy, respectively. CONCLUSION: The early and late post-sclerotherapy MR findings of aneurysmal bone cysts were reported in this study.

Aneurysmal bone cysts in the spine, causing neurological compromise: safety and clinical efficacy of sclerotherapy utilizing sodium Tetradecyl sulfate foam.

OBJECTIVE: To assess the clinical efficacy, technical feasibility, and safety profile of percutaneous sclerotherapy utilizing sodium tetradecyl-sulfate foam (STS) as a first-line treatment strategy for aggressive spinal aneurysmal bone cysts (sABCs) presenting with neurological compromise. MATERIALS AND METHODS: Between July 2013 and September 2019, eight consecutive patients (5 males; 3 females; mean age 22±17, range 7-52) underwent fluoroscopic/CT-guided intraosseous sclerotherapy for sABCs. Pain and/or neurological compromise was the primary indications. Procedural data, complications, imaging, and clinical results were analyzed. RESULTS: Technical success was achieved in all cases. Mean procedure time was 25±15 min (range 6-167); 1 to 5 repeat treatment cycles (mean 3.7±1.2) utilizing a mean 2.6mls±1.3 (range 1-6) of agitated 3% STS, with a DLP mean dose of 158±91 mGy*cm (range 62-331) per procedure. One reported a minor complication (pain), but no significant complications. Two patients had persistent neurological deficit due to cord compression despite successful sclerotherapy, requiring surgical resection (and were thereby excluded from the final outcome analysis). The remaining six patients demonstrated a significant reduction in tumor volume (p = 0.028), pain (p = 0.027), and SINS (spinal instability neoplastic score) (p = 0.027) at up to 5 years of follow-up (mean 20 ± 16.7, range 7-51 months). CONCLUSION: Percutaneous sclerotherapy with STS is a minimally invasive, technically feasible, safe, and effective first-line treatment for primary sABCs causing pain and neurological compromise, alleviating the need for extensive surgery. It is most effective with three or more treatment cycles, in patients with higher SINS, pain scores, or tumor volumes at the initial presentation.

Efficacy of Lesion Specific Portals in Endoscopic Treatment of Calcaneal Bone Cyst: A Case Report and Literature Review.

Background: Calcaneal bone cysts rarely occur and most of them are known to be benign. Among them, simple bone cysts (SBCs) third most commonly occur in the calcaneus and of the many surgical treatment options, endoscopic curettage is recently gaining popularity among surgeons due to its advantages of minimal invasiveness and optimal visualization. As for portal placement for endoscopy, two lateral portals are considered a standard technique, but no rationale has been established for SBCs with abnormal geometry. This case report suggests an SBC with secondary aneurysmal change located outside the Ward's triangle, as well as an appropriate endoscopic approach. Case Presentation: An 18-year-old male high school student presented with a main complaint of pain at the hind foot level for the past one year, without significant improvement from conservative treatment. An endoscopic curettage through the lesion specific two posterior portals and bone graft using allogeneic cancellous bone were performed. SBC with a secondary aneurysmal bone cyst was diagnosed on pathology. At a one-year follow-up, the patient was painless and had returned to his regular activities. Physical and radiographic examinations revealed that the lesion was completely healed without any evidence of recurrence. Conclusion: For calcaneal bone cysts located at the posterior aspect of the calcaneus, eccentrically medial and abnormally long anterior-posteriorly, we suggest an endoscopic procedure using lesion specific portals such as two posterior portals.

Percutaneous treatments of primary aneurysmal bone cysts: systematic review and meta-analysis.

PURPOSE: To systematically review the literature to determine recurrence rates of percutaneous treatments for primary aneurysmal bone cysts (ABC). METHODS: Search strategies were performed in the following databases: PubMed, SCIELO, LILACS and BVS, using terms in English, Spanish and Portuguese (PROSPERO Registration Number: CRD42020170340). Longitudinal studies, either observational or clinical trials, with at least five patients and with a mean of 18 months of follow-up were included. Studies had to use any type of percutaneous treatments and report the recurrence rates of primary ABC treatment. Studies selection, data extraction and risk of bias assessment were performed independently by two researchers. A global meta-analysis was carried out to assess the proportion of recurrence. Studies were categorized into two subgroups: selective arterial embolization and sclerotherapy. RESULTS: Thirteen studies were included in the present study. The average success rate of percutaneous treatments for ABC was 91.11%, with a total of 37 lesions recurrences in the 416 patients. The sex ratio was 1:1. The subgroup of sclerotherapies presented a lower proportion of recurrence. The proportion of recurrence in the subgroup of selective arterial embolization was 19% (95%IC 12.11-27.54) and that of sclerotherapies was 6% (95%IC 3.65-9.19). CONCLUSIONS: Both percutaneous treatments for ABC are effective, showing a lower rate of recurrence. Sclerotherapy treatments seem to be promising, but further clinical trials must be conducted with a longer follow-up.

[Radiologic diagnosis of pathologic fractures]. / Radiologische Diagnostik pathologischer Frakturen.

BACKGROUND: Pathologic fractures are fractures that occur without an adequate traumatic event due to focal benign or malignant skeletal lesions. The most common causes of pathologic fractures are cystic bone lesions, plasmocytoma or multiple myeloma, and the development of osseous metastases, which is increasing due to an aging general population and advances in cancer treatment. The differentiation of pathologic fractures from stress fractures, especially osteoporotic insufficiency fractures is crucial for correct treatment planning. OBJECTIVES: This review intends to explain the imaging characteristics of pathologic fractures. Moreover, it explains the role of imaging when pathologic fractures are suspected. In addition, the Mirels' score and the SINS (Spinal Instability Neoplastic Score), which are powerful yet easy-to-use tools for the assessment of the fracture risk of benign or malignant bony lesions of the extremities and the vertebral column, shall be introduced. MATERIALS AND METHODS: A PubMed literature search with the following terms was conducted: "pathologic fracture", "fatigue fracture", "insufficiency fracture", "treatment of pathologic fractures", "imaging of pathologic fractures", "fracture risk", "bone metastases", "MRI of pathologic fractures", "CT of pathologic fractures", "differentiation of pathologic and insufficiency fractures", "Mirels' score", "SINS" and "spinal instability neoplastic score". RESULTS: The definitions of pathologic, fatigue, and insufficiency fractures are explained. Moreover, the role of imaging in the clinical workup of suspected pathologic fractures and the differentiation of pathologic fractures from fatigue or insufficiency fractures as well as common scoring systems to assess the fracture risk of pathologic fractures are described.

[The clinical effect of autologous osteochondral transplantation via biplanar osteotomy for osteochondral lesions of the talus combined with subchondral cysts].

Objective: To examine the clinical effect of autologous osteochondral transplantation via biplanar osteotomy for osteochondral lesions of the talus combined with subchondral cysts. Methods: A retrospective analysis of 25 patients who underwent autogenous osteochondral transplantation via biplanar osteotomy for treatment of talus osteochondral injury combined with subchondral cysts at Department of Orthopaedics, First Affiliated Hospital of Xinjiang Medical University from December 2015 to December 2018 were conducted.There were 21 males and 4 females, aged 35.5 years(range: 21 to 47 years).The extent and depth of cartilage damage of patients were evaluated under arthroscopy.The Outerbridge classification of patients were stage Ⅱ-Ⅳ. Through the anterior and medial incision of the medial malleolus, bilateral osteotomy of the medial malleolus was performed. The osteotomy block was turned down to reveal the cartilage damage site. The abnormal cartilage was completely removed and the sclerotic wall of cyst was completely removed with a spatula.Then the healthy cartilage from the same knee joint was transplanted to the talus cartilage damage area. The preoperative and postoperative visual analogue scale(VAS), American Orthopedic Foot Andankle Society-Ankle Hindfoot Scale (AOFAS-AH) and Karlsson-Peterson score and Lysholm score of knee joint were recorded. Data were analyzed by paired-samples t-test. Results: All of patients were followed up for 25.6 months (range: 12 to 48 months) .The VAS decreased from 6.5±1.3 to 1.9±1.3 (t=8.13, P=0.00) .AOFAS-AH increased from 62.4±3.3 to 88.0±2.4 (t=-31.51, P=0.00) .Karlsson-Peterson scores increased from 59.8±2.7 to 85.2±3.5 (t=-25.50, P=0.00) . While there was no statistical different in Lysholm score of knee joint (92.5±1.3 vs. 92.0±1.3, t=1.93, P=0.065) . No complications like infection, translated cartilage necrosis, cycst residual, nonunion, persistent pain in donor site. Conclusion: Autologous osteochondral transplantation via biplanar osteotomy has satisfactory effect for patients with osteochondral lesions of the talus combined with subchondral cysts.

Aneurysmal bone cyst treated with percutaneous doxycycline: is a single treatment sufficient?

OBJECTIVE: The purpose of this case series is to report on the effectiveness of a single percutaneous injection of doxycycline as a primary treatment for aneurysmal bone cyst (ABC). MATERIALS AND METHODS: A retrospective cohort study was conducted on seven patients diagnosed with ABC at various anatomical sites, with the intention to treat by a single percutaneous injection of doxycycline. Mean patient age was 14 years. RESULTS: Signs of treatment response were seen in six of seven patients after one injection. Three of the seven received a second treatment, despite signs of response. Another had expansion of the lesion after treatment, requiring excision. In total, three patients had a single injection of doxycycline as their sole treatment and another three showed signs of response after a single injection. CONCLUSIONS: A single percutaneous injection of doxycycline should be considered a viable primary treatment option for ABC.

Immediate Insertion of Dental Implants Immediate Insertion in Bilateral Traumatic Bone Cysts With or Without a Bone Grafting Material: A 5-Year Follow-Up Case Report.

This case report describes the rehabilitation of a patient who received dental implants in traumatic bone cyst areas (TBC). A 24-year-old male patient sought dental treatment for the bilateral absence of the mandibular second premolars. Radiographic examination revealed bilateral large radiolucent images in the mandible body. Surgical exploration confirmed the diagnosis of TBC. Rehabilitation with dental implants was performed using different approaches on each side. One cystic cavity was filled with blood clot and allogenic bone graft; the other was filled only with blood clot. After 5 years, the implants are osseointegrated and functioning. The filling of the traumatic bone cyst cavity with local blood clot in contact with the implant presented clinical and radiographic success similar to that obtained with filling with bone graft in the same patient. Thus, in this patient, the blood clot-only approach can be considered as a viable, safe-low cost alternative to blood clot and grafting material.

Peri-prosthetic bone cysts after total ankle replacement. A systematic review and meta-analysis.

BACKGROUND: Periprosthetic cystic osteolysis is a well-known complication of total ankle replacement. Several theories have been proposed for its aetiology, based on individual biomechanical, radiological, histopathology and outcome studies. METHODS: Studies that met predefined inclusion/exclusion criteria were analysed to identify literature describing the presence of peri-prosthetic ankle cystic osteolysis. Quantitative data from the selected articles were combined and statistically tested in order to analyse possible relations between ankle peri-prosthetic bone cysts and specific implant characteristics. RESULTS: Twenty-one articles were elected, totalizing 2430 total ankle replacements, where 430 developed peri-prosthetic cystic osteolysis. A statistically significant association (P<.001) was found between the presence of bone cysts and non-anatomic implant configuration, hydroxyapatite-coating, mobile-bearing and non tibial-stemmed implants. No significant association existed between the type of constraining and the presence of cysts (P>.05). CONCLUSIONS: Non-anatomic, mobile-bearing, hydroxyapatite-coated and non tibial-stemmed total ankle replacements are positively associated with more periprosthetic bone cysts.

TREATMENT OF UNICAMERAL BONE CYSTS IN CHILDREN: A COMPARATIVE STUDY.

Unicameral bone cysts (UBC) are benign bone tumor-like lesions. Mostly they are located in the metaphyseal-diaphyseal region of long bones in children and adolescents. The etiology of UBC is still unclear. There is no consensus about the protocol of UBC treatment. The aim of this study was to evaluate the effectiveness of three different techniques for the treatment of UBC. This study included 129 pediatric patients with UBC treated at University Children's Hospital in Belgrade during the 8-year period. The mean follow up was 7.14 years. The following parameters were observed: gender, age, site, length of cyst, cyst index, cortical thickness, presentation of pathologic fracture, healing of cyst, treatment complications and length of hospitalization. These parameters were correlated to three treatment modalities, i.e. intracystic methylprednisolone acetate injection (group 1), curettage with bone grafting (group 2) and osteoinductive procedure using demineralized bone matrix (group 3). We found statistically significant differences in healing of the cysts and length of hospital treatment between groups 1 and 2, and between groups 2 and 3. In conclusion, complete healing of UBC can be achieved only using open surgery procedure. Intracystic methylprednisolone acetate instillation can be considered a good option for initial treatment of UBC.