Tumors Of Long Bones Research Articles

OUTCOMES OF SHOULDER JOINT ENDOPROSTHETICS AFTER REMOVAL OF TUMORS IN THE HUMERUS

Introduction. The use of endoprostheses of the shoulder joint is possible with primary and secondary (metastatic) tumor lesions of the proximal part of the humerus. The possibility of using both individual oncological endoprostheses and modular oncological endoprostheses for tumors of the proximal part of the humerus is reported. Aim. To assess the effectiveness of restoring the function of the shoulder joint and upper limb and improving the patient's quality of life after shoulder joint arthroplasty for tumors of the proximal part of the humerus. Materials and methods. The results of the treatment of 27 patients who underwent shoulder arthroplasty in the conditions of the clinical departments of the "Institute of Traumatology and Orthopedics of the National Academy of Medical Sciences of Ukraine" for tumors of the proximal part of the humerus from 2014 to 2024 were evaluated. Endoprosthesis was performed in 22 (81.5%) patients with primary tumors of the proximal part of the humerus and in 5 (18.5%) with metastatic tumors. Endoprosthesis of the shoulder joint was performed with individual oncological endoprostheses in 24 (88.9%) patients and modular oncological endoprostheses in 3 (11.1%) patients. Arthroplasty was primary in 25 (92.6%) patients and secondary in 2 (7.4%) patients. Results. During follow-up, 3 (11.1%) patients died with an average follow-up period of 10.3±1.9 months, the other 24 (88.9%) were alive, with an average follow-up period of 88.1±8.7 months. The overall frequency of complications in our study was 6 (22.2%) cases, 3 (11.1%) patients had an infectious complication in the late postoperative period after 12, 24 and 36 months, 1 (3.7%) patient had aseptic loosening of the leg of the endoprosthesis after 36 months, in 2 (7.4%) patients after 5 and 6 months, dislocation of the head of the endoprosthesis from the joint cavity was noted. Local tumor recurrence was observed in 2 (7.4%) patients. The overall mean MSTS total limb functional outcome after shoulder arthroplasty for all 27 patients was 74.2%, and of the 24 patients who survived, the mean limb functional outcome after shoulder arthroplasty was 78.4%. The patients' quality of life (according to the EORTQ-QLQ-С30 questionnaire) increased from 32 points in the preoperative period to 78 points after shoulder joint replacement. Conclusions. Endoprosthetics is a modern method for reconstructing bone segments in the surgical treatment of tumors of long bones in the limbs. This method allows for the replacement of bone defects of any size (volume) and length. Shoulder joint endoprosthetics within the framework of combination and multimodal treatment of primary and metastatic tumors of the proximal part of the humerus provides restoration of both shoulder joint functions and the upper limb as a whole, thereby improving the quality of life for this group of patients.

Computed tomography-based radiomics machine learning models for differentiating enchondroma and atypical cartilaginous tumor in long bones.

To explore the value of CT-based radiomics machine learning models for differentiating enchondroma from atypical cartilaginous tumor (ACT) in long bones and methods to improve model performance.59 enchondromas and 53 ACTs in long bones confirmed by pathology were collected retrospectively. The features were extracted from preoperative CT images of these patients, and least absolute shrinkage and selection operator (LASSO) regression was used for feature selection and dimensionality reduction. The selected features were used to construct classification models by thirteen machine learning algorithms. The data set was randomly divided into a training set and a test set at a proportion of 7:3 by ten-fold cross-validation to evaluate the performance of these models.A total of 1199 features were extracted, 9 features were selected, and 13 radiomics machine learning models were constructed. The area under the curve (AUC) of 11 models was more than 0.8, and that of 3 models was more than 0.9. The Extremely Randomized Trees model achieved the best performance (AUC = 0.9375 ± 0.0884), followed by the Adaptive Boosting model (AUC = 0.9188 ± 0.1010) and the Linear Discriminant Analysis model (AUC = 0.9062 ± 0.1459).CT-based radiomics machine learning models had great ability to distinguish enchondroma and ACT in long bones. By using filters to deeply mine high-order features in the original image and selecting appropriate machine learning algorithms, the performance of the model can be improved. · CT-based radiomics machine learning models can distinguish enchondroma and ACT in long bones.. · Using filters and selecting advanced machine learning algorithms can improve model performance.. · Clinical features have limited utility in distinguishing enchondroma and ACT in long bones.. · Hong R, Li Q, Ma J et al. Computed tomography-based radiomics machine learning models for differentiating enchondroma and atypical cartilaginous tumor in long bones. Fortschr Röntgenstr 2024; DOI 10.1055/a-2344-5398.

Endoprosthetic replacement with preservation of the epiphysis for proximal tibial reconstruction after osteosarcoma resection in children: a case report

BackgroundLimb salvage surgery is an important method for treating malignant tumors of the bone involving the adjacent parts of the major joints in children. This technique allows for preservation of limb function, especially in the lower limb. However, the reconstruction of the proximal end of the tibia after removing the tumor mass with a rational scale to preserve the total knee joint and reduce limb length discrepancy presents a challenge.Case presentationWe present a case of osteosarcoma of the proximal tibia. After being treated with an extended tumor resection, the proximal tibia of the child was restructured using endoprosthetic replacement with epiphyseal preservation. This procedure preserves the entire articular surface and growth plate of the knee joint of the affected limb and provides a feasible alternative protocol for retaining the function and growth potential of the affected limb. The patient remained disease-free and normal limb motor function was observed during the 3.5 year follow-up since the initial surgery.ConclusionsPreservation of the epiphysis enabled our patient to perform better limb function after limb-saving surgery as a result of his undamaged knee joint and minimized limb-length discrepancy. We believe that endoprosthetic replacement with preservation of the epiphysis can provide the best strategy for reconstruction after resection of focal malignant tumors in long bones without epiphytic involvement.

X-rays radiomics-based machine learning classification of atypical cartilaginous tumour and high-grade chondrosarcoma of long bones

Atypical cartilaginous tumour (ACT) and high-grade chondrosarcoma (CS) of long bones are respectively managed with active surveillance or curettage and wide resection. Our aim was to determine diagnostic performance of X-rays radiomics-based machine learning for classification of ACT and high-grade CS of long bones. This retrospective, IRB-approved study included 150 patients with surgically treated and histology-proven lesions at two tertiary bone sarcoma centres. At centre 1, the dataset was split into training (n=71 ACT, n=24 high-grade CS) and internal test (n=19 ACT, n=6 high-grade CS) cohorts, respectively, based on the date of surgery. At centre 2, the dataset constituted the external test cohort (n=12 ACT, n=18 high-grade CS). Manual segmentation was performed on frontal view X-rays, using MRI or CT for preliminary identification of lesion margins. After image pre-processing, radiomic features were extracted. Dimensionality reduction included stability, coefficient of variation, and mutual information analyses. In the training cohort, after class balancing, a machine learning classifier (Support Vector Machine) was automatically tuned using nested 10-fold cross-validation. Then, it was tested on both the test cohorts and compared to two musculoskeletal radiologists' performance using McNemar's test. Five radiomic features (3 morphology, 2 texture) passed dimensionality reduction. After tuning on the training cohort (AUC=0.75), the classifier had 80%, 83%, 79% and 80%, 89%, 67% accuracy, sensitivity, and specificity in the internal (temporally independent) and external (geographically independent) test cohorts, respectively, with no difference compared to the radiologists (p≥0.617). X-rays radiomics-based machine learning accurately differentiates between ACT and high-grade CS of long bones. AIRC Investigator Grant.

Perioperative hemorheological status of oncological patients with primary knee replacement

Introduction. Endoprosthesis of large joints is associated with high risk of venous thromboembolism. Researchers focus on biochemical characteristics of homeostasis, blood clotting in particular, as the main reason for abnormal blood flow. At the same time, biophysical condition of homeostasis, namely decreased blood fluidity, is rarely considered. Study of rheological behavior of blood after primary oncological endoprosthesis of large joints in patients can potentially affect the selection of perioperative thromboprophylaxis and patient rehabilitation approach.Aim. To study the indicators of the hemorheological status of patients with tumours of long bones in the preand postoperative periods of primary oncological knee replacement.Materials and methods. The study included 36 patients (26 men and 10 women, mean age 46 years) without cardiovascular diseases and pathology of the veins of the lower limb admitted to the Russian Scientific Center of Roentgen Radiology for oncological endoprosthesis of the knee joint. All patients were prescribed: an antiplatelet agent (acetylsalicylic acid) and an anticoagulant (enoxaparin sodium 40 mg daily). Distal resection of the femur (on average 14 cm) was performed in 28 patients, and proximal resection of the tibia (on average 12 cm) in 8 patients, followed by knee replacement. Before the operation, on the 1st and 6th days after the operation, the hemorheological status and the state of the hemostasis system were evaluated in all patients. To determine the reference values, 24 healthy people were examined, comparable in gender and age. Statistical analysis using Statistica 10.0.Results. During the preoperative examination, integral assessment showed the differences in the severity of hemorheological disorders between patients, and two groups were identified: Group 1 – 21 (61 %) patients whose hemorheological disorders were classified as severity degree I, and Group 2 – 14 (39 %) patients with severity degree II d. On day 1 after the surgery, both patient groups showed negative dynamics: hemorheological disorders in group 1 worsened from grade I to II d., and in group 2 to III d. (critical) (p <0.05). On day 6, the parameters did not change significantly in all patients. Similar dynamic changes were observed in the haemostasis system.Conclusion. Activation of the blood coagulation system and deterioration of hemorheology occurred after surgery during administration of anticoagulant and antiplatelet therapy. None of the patients had venous thromboembolic complications, however the risk of their development remained high. A differential model describing hemorheological status can be useful for selection of thromboprophylaxis and rehabilitation methods which include physical factors that improve the hemorheological profile: low-frequency magnetic and/or laser therapy in patients.

Literature Review, Case Presentation and Management of Non-ossifying Fibroma of Right Angle of Mandible: More Than just a Cortical Defect!

Non-ossifying fibroma (NOF) of jaw bones are rare. While NOF is the most common benign bone tumor of long bones with pathognomonic radiological features and bear a tendency for self-regression, gnathic NOF appears to be comparatively larger in size and behave more aggressively. A 16 years old female patient reported with painless swelling of the right side of the face of 4 months duration. Radiographic analysis showed a unilocular radiolucent lesion of right angle of the mandible with ill-defined margins, cortical perforation and thinning of inferior border. The lesion was provisionally diagnosed as odontogenic keratocyst/unicystic ameloblastoma and incisional biopsy was performed. The histopathological features and immunohistochemical characteristics favored a diagnosis of NOF. The lesion was excised and reconstructed. The excised specimen confirmed the diagnosis. There are no signs of recurrence at 18 months follow-up. NOF should be considered in the differential diagnosis of uni-/multilocular radiolucencies of jaws particularly theposterior mandible.

Features of routing, diagnosis and combined treatment of pathological fractures of long tubular bones of tumor etiology

Introduction. In the structure of fractures of long tubular bones, pathological fractures account for about 1 %, and 2/3 of all cases are pathological fractures associated with bone metastases. Primary bone tumors are complicated by the development of a pathological fracture in 1– 10 % of cases, bone metastases in 8–30 % of cases. With a pathological fracture, as the primary manifestation of the tumor process, as a rule, patients come to the attention of orthopedic traumatologists providing emergency care. In the practice of oncologists, there are often patients with bone tumors who have performed deliberately non-radical surgical interventions associated with insufficient oncological alertness of traumatologists.Aim. To study and present the results of combined treatment of patients with bone tumors complicated by a pathological fracture.Materials and methods. The results of treatment and observation of 159 patients with tumors of long tubular bones complicated by a pathological fracture or the threat of its development, who received combined or surgical treatment and were observed in the polyclinic of the Republican Oncological Dispensary from 2008 to 2020, were analyzed.Results. A pathological fracture that has taken place, in the absence of somatic contraindications, is not a contraindication to neoadjuvant treatment, which allows performing organ-preserving surgical treatment with optimal local and systemic control. However, with verified bone metastases, when segmental bone resections are not shown, and the diagnosis of myeloma (solitary plasmocytoma) is established, it is permissible to perform surgery in a trauma hospital, after consulting an oncologist.Conclusion. The combined approach in the treatment of malignant bone tumors complicated by a pathological fracture makes it possible to perform a functional-saving, organ-preserving surgical intervention, significantly reducing the risk of tumor recurrence and systemic progression.

Primary Tumors of Long Bones at The Regional Hospital of Sokode: Epidemiological, Diagnostic and Therapeutic Characteristics

Primary Tumors of Long Bones at The Regional Hospital of Sokode: Epidemiological, Diagnostic and Therapeutic Characteristics

CORTICAL WINDOW RECONSTRUCTION WITH CEMENT AUGMENTED SCREW FIXATION AFTER INTRALESIONAL CURETTAGE OF LOW-GRADE CHONDROSARCOMAS: A SIMPLE METHOD WITH CLINICAL RESULTS

Purpose:
 
 Intralesional curettage with a local adjuvant is a reliable surgical method in the treatment of low-grade chondrosarcomas (LGC). In order to maintain stability, some authors recommend osteosynthesis following intralesional treatment. However, larger osteosynthesis materials may increase complications as well as disturbing postoperative MRI evaluation. In this study, we describe a simple method of cortical window reconstruction with cement-augmented screw fixation.
 
 Methods:
 
 22 patients with LGC were enrolled in this retrospective study who underwent surgical intervention between 2011-2021. All patients were treated in the same manner by intralesional curettage, cement augmentation and fixation with titanium screws embedded in the cement. The clinical outcome was assessed, using the MSTS Score.
 
 Results:
 
 The mean age at diagnosis was 44,5 and the mean follow up duration was 56,2 months. The mean long dimension of the cortical window was 4,8 cm for reconstructions with one screw and 6,2 cm for reconstructions with two screws. All of the patients showed excellent clinical outcomes with a mean MSTS score percentage of 91,3. We did not encounter any major complications postoperatively. On MRI evaluations, the image distortion due to thin titanium screw was minimal and cement bone interface was clearly visible without any disturbance.
 
 Conclusion:
 
 The convenient use of cement-augmented screw fixation may be a good tool for the reconstruction of cortical window in the treatment of intramedullary tumours of long bones and give a potential chance of obtaining better MRI images without any disturbances postoperatively.

Microwave in situ inactivation in the treatment of bone giant cell tumor: a mid-term descriptive study.

To evaluate the mid-term clinical efficacy of microwave in situ inactivation combined with bone grafting or polymethyl methacrylate (PMMA) filling in the treatment of giant cell tumor of bone (GCTB). This is a retrospective, descriptive, and analytical study. A total of 30 GCTB patients received microwave in situ inactivation from January 2012 to January 2020, whose clinical recurrence rate was evaluated at the last follow-up after microwave in situ inactivation surgery. The Musculoskeletal Tumor Society (MSTS) function score was used to evaluate the postoperative clinical panoramic results. All patients were followed up for 21 to 110months, with an average of 63.79months. Distal femur (40%) and proximal tibia (28%) had a higher rate of GCTB incidence. Seventeen percent of tumor patients suffered from associated pathologic fracture. The rate of Campanacci classification stage III was 60%. The average MSTS score was evaluated as 27.53 points overall at the last follow-up. In terms of complications, three, two, two and one cases developed fat liquefaction, controllable tissue rejection reaction, incision infection and degenerative changes around lesion joint, respectively, without in situ recurrences and reoperation as well as distant lung metastasis. The method of microwave in situ inactivation combined with bone grafting or PMMA filling is prudently recommended as one of the options for the limb salvage treatment of giant cell tumor of long and periarticular bone. IV: case series.

Differentiating Enchondromas and Atypical Cartilaginous Tumors in Long Bones with Computed Tomography and Magnetic Resonance Imaging.

The differentiation between the atypical cartilaginous tumor (ACT) and the enchondromas is crucial as ACTs require a curettage and clinical as well as imaging follow-ups, whereas in the majority of cases enchondromas require neither a treatment nor follow-ups. Differentiating enchondromas from ACTs radiologically remains challenging. Therefore, this study evaluated imaging criteria in a combination of computed tomography (CT) and magnetic resonance (MR) imaging for the differentiation between enchondromas and ACTs in long bones. A total of 82 patients who presented consecutively at our institution with either an ACT (23, age 52.7 ±18.8 years; 14 women) or an enchondroma (59, age 46.0 ± 11.1 years; 37 women) over a period of 10 years, who had undergone preoperative MR and CT imaging and subsequent biopsy or/and surgical removal, were included in this study. A histopathological diagnosis was available in all cases. Two experienced radiologists evaluated several imaging criteria on CT and MR images. Likelihood of an ACT was significantly increased if either edema within the bone (p = 0.049), within the adjacent soft tissue (p = 0.006) or continuous growth pattern (p = 0.077) were present or if the fat entrapment (p = 0.027) was absent on MR images. Analyzing imaging features on CT, the likelihood of the diagnosis of an ACT was significantly increased if endosteal scalloping >2/3 (p < 0.001), cortical penetration (p < 0.001) and expansion of bone (p = 0.002) were present and if matrix calcifications were observed in less than 1/3 of the tumor (p = 0.013). All other imaging criteria evaluated showed no significant influence on likelihood of ACT or enchondroma (p > 0.05). In conclusion, both CT and MR imaging show suggestive signs which can help to adequately differentiate enchondromas from ACTs in long bones and therefore can improve diagnostics and consequently patient management. Nevertheless, these features are rare and a combination of CT and MR imaging features did not improve the diagnostic performance substantially.

CENTRAL GIANT CELL LESION TREATMENT IN MAXILLA WITH DENOSUMAB: A NOVEL APPROACH

Central giant cell lesion (CGCL) is a benign nonneoplastic intraosseous lesion usually treated with aggressive surgical excision. Denosumab, a monoclonal antibody, is widely used in the treatment of giant cell tumors in long bones and has been proposed as an alternative therapy for CGCL in the jaw. A 16-year-old patient presented with recurrence of CGCL after 1 year of surgical resection, with removal of the lesion and extraction of 7 maxillary teeth. Therefore, pharmacologic treatment with subcutaneous denosumab was proposed with an injection of 120 mg on days 0, 7, 14, and 21 of the first month, followed by equal doses every 40 days. After 6 months of treatment, the imaging exams showed a significant lesion reduction of 45%. Treatment with denosumab was continued for another 6 months to allow a less aggressive surgery or eliminate the need for surgery.

Errors and complications in the treatment of patients with primary tumors of the lower limb long bones by the Ilizarov method

Based on the analysis of the treatment results of 133 patients with primary tumors of the lower limb long tubular bones, we describe the errors and complications of the Ilizarov method. We identified and analyzed the main groups of errors (organizational, tactical, and technical) and studied the treatment complications associated with them. These complications are not accompanied by significant anatomical and functional disorders, in the vast majority are treated by conservative measures and do not lead to the necessity to stop osteosynthesis. Systematization of errors and related complications determines a set of therapeutic and preventive measures for their prevention, while providing a more effective and high-quality rehabilitation of patients, reducing the time of hospital treatment of patients with tumor pathology of the long tubular bones.

Computer 3D modeling of radiofrequency ablation of atypical cartilaginous tumours in long bones using finite element methods and real patient anatomy

BackgroundRadiofrequency ablation (RFA) is a minimally invasive technique used for the treatment of neoplasms, with a growing interest in the treatment of bone tumours. However, the lack of data concerning the size of the resulting ablation zones in RFA of bone tumours makes prospective planning challenging, needed for safe and effective treatment.MethodsUsing retrospective computed tomography and magnetic resonance imaging data from patients treated with RFA of atypical cartilaginous tumours (ACTs), the bone, tumours, and final position of the RFA electrode were segmented from the medical images and used in finite element models to simulate RFA. Tissue parameters were optimised, and boundary conditions were defined to mimic the clinical scenario. The resulting ablation diameters from postoperative images were then measured and compared to the ones from the simulations, and the error between them was calculated.ResultsSeven cases had all the information required to create the finite element models. The resulting median error (in all three directions) was -1 mm, with interquartile ranges from -3 to 3 mm. The three-dimensional models showed that the thermal damage concentrates close to the cortical wall in the first minutes and then becomes more evenly distributed.ConclusionsComputer simulations can predict the ablation diameters with acceptable accuracy and may thus be utilised for patient planning. This could allow interventional radiologists to accurately define the time, electrode length, and position required to treat ACTs with RFA and make adjustments as needed to guarantee total tumour destruction while sparing as much healthy tissue as possible.

Outcomes and complications of organ-sparing treatment of patients with tumor and tumor-like conditions of the forearm long bones

Introduction.Surgical treatment of tumors of the distal part of the forearm has always been complicated. Though there are many methods of reconstruction of defects of the long bones of this area after resection, the optimal technique is still debated.The study objectiveis to analyze the results of surgical treatment of tumors and tumor-like conditions of the forearm long bones, rate of postoperative complications, and techniques of their correction.Materials and methods. The article presents data on 75 patients with tumor and tumor-like conditions of the forearm long bones. Diagnosis was histologically verified. In 58 (77.3 %) patients, benign giant cell tumor was diagnosed, in 3 (4 %) patients – malignant giant cell tumor, in 3 (4 %) patients – osteogenic sarcoma, in 3 (4 %) patients – chondrosarcoma, in 6 (8 %) patients – fibrous dysplasia. All patients underwent surgical treatment of varying volume. During the study, analysis of complications of surgical treatment was performed.Results.Postoperative complications of various nature developed in 17 (22.7 %) of 75 patients between 2 weeks and 2 years after treatment. They mostly developed after segmental resection of the forearm bones with autoplasty (38.1 %) and segmental bone resection (21.4 %), as well as after excochleation with cementoplasty (16.1 %). The most frequent complications were autotransplant lysis (in 4 (19.1 %) cases), its fracture (in 2 (9.5 %) cases), and infections and inflammatory complications (in 2 (9.5 %) cases). After segmental resection with endoprosthesis, only 1 (11.1 %) patient experienced endoprosthesis head instability in the early postoperative period which led to re-endoprosthesis. Local recurrence was observed in 6 (19.4 %) of 31 patients with gigantic-cell tumors after excochleation and in 4 (28.6 %) of 14 patients after segmental resection. In 2 (14.3 %) cases, progression of the main disease was observed in the form of pulmonary metastases.Conclusion.Excochleation with cementoplasty is the method of choice in benign tumors of the forearm bones in the absence of soft-tissue component, destruction of the cortical layer, advancement of the tumor to the joint surface. In case of benign tumors in the absence of soft-tissue component and destruction of the cortical layer, and in the presence of tumor advancement to the joint surface, the optimal technique is segmental bone resection with substitution of the defect with endoprosthesis.

Combined treatment of giant cell bone tumor

Introduction. Giant cell tumor refers to tumors with an uncertain malignancy potential, has a locally aggressive course. Intra-focal resections performed for a giant cell tumor of long tubular bones are accompanied by the development of relapse in 30–46 % of cases. The combination of pathogenetic therapy with surgical intervention makes it possible to reduce the frequency of relapses in operable tumors after marginal and intra-focal resections, and in inoperable tumors to provide local control and relieve pain. Objective – to analyze the results of combined treatment of patients with giant cell bone tumor. Materials and methods. In the conditions of Republican Clinical Oncological Dispensary of the Ministry of Health of the Republic of Tatarstan, 13 patients aged 20 to 63 years are in the process of combined treatment of a giant cell tumor. As of November 2021, 7 patients have completed treatment.Results. Among the 7 patients who completed treatment, 6 people were operated on (1 patient refused surgery). In 5 patients, intra-focal resection of the tumor with osteoinductive material “BoneMedic-S” was performed, in 1 patient with a giant cell tumor of the sciatic bone, resection of the sciatic bone was performed without reconstruction. 1 patient with a widespread tumor (sacral lesion) receives supportive treatment. Conclusion. The combined approach in the treatment of giant-cell bone tumor allows performing a functional-saving, organpreserving surgical intervention, significantly reducing the risk of tumor recurrence and its malignant transformation.

Математичне обґрунтування застосування різних методик остеосинтезу патологічного перелому проксимального відділу стегнової кістки при лікуванні метастатичних пухлин довгих кісток кінцівок

Метастатичне ураження кісток є тяжким ускладненням онкологічної хвороби. Метастази в кістки виявляються у 17–50 % хворих із солідними злоякісними пухлинами та є третьою за частотою локалізацією після метастатичного ураження легень і печінки. Основними клінічними проявами метастатичного ураження кісток є біль, патологічні переломи, що виникають у 8–30 % випадків, компресія спинного мозку та гіперкальціємія, що значною мірою визначає тяжкість стану хворого, а в ряді випадків є причиною летальності. Вибір методики остеосинтезу при метастатичному ураженні довгих кісток кінцівок є актуальним у зв’язку з тим, що потрібна надійна фіксація відламків кістки, тому що в більшості випадків зрощення кістки не відбувається. Проведено біомеханічне дослідження з випробуванням на міцність і жорсткість нативної моделі стегнової кістки з наявним порожнистим дефектом у проксимальному її відділі трьома різними варіантами металофіксаторів: проксимальним стегновим стрижнем, накістковою пластиною та апаратом зовнішньої фіксації Костюка. Порівнюючи показники напружень на фрагментах моделі стегнової кістки між собою, слід відмітити, що при застосуванні апарата зовнішньої фіксації Костюка спостерігається зростання значень напружень майже у 2 рази порівняно зі значеннями при застосуванні проксимального стегнового стрижня та накісткової пластини. Значення напружень на кістці при застосуванні апарата зовнішньої фіксації перевищують поріг міцності кортикальної тканини. Показники напружень на елементах фіксації зростають майже у 9 разів при застосуванні апарата зовнішньої фіксації Костюка порівняно із значеннями при застосуванні проксимального стегнового стрижня та у 3 рази при використанні накісткової пластини. Значення напружень на металевих конструкціях при застосуванні апарата зовнішньої фіксації Костюка не перевищують поріг їх міцності. Порівнюючи отримані показники переміщень цілком усієї моделі стегнової кістки, тобто проксимального її відділу відносно закріпленого дистального відділу, можна спостерігати майже рівнозначні показники при застосуванні проксимального стегнового стрижня та накісткової пластини. Показники переміщень при застосуванні апарата зовнішньої фіксації Костюка майже у 2 рази вище, ніж при застосуванні проксимального стегнового стрижня та накісткової пластини. В усіх варіантах фіксації відбувається перерозподіл навантаження на металеві конструкції фіксаторів, тобто основну функцію утримання несе на собі фіксатор, тим самим розвантажуючи саме кістку та ділянку її перелому. В результаті експериментального дослідження встановлено, що більш надійну фіксацію уламків забезпечують проксимальний стегновий стрижень та накісткова пластина. Апарат зовнішньої фіксації Костюка в даних умовах справляється з поставленим завданням гірше. Відбувається значна деформація стрижнів апарата зі зминанням кістки у ділянці перелому та збільшенням рухливості відламків. Дані експериментального дослідження можуть бути розглянуті як варіант вибору методики остеосинтезу у хворих із метастатичним ураженням кісток кінцівок.

Reconstruction and repair, using mini-plate and bone graft for persons living with HIV with giant cell tumor of long bone: retrospective analysis of a single-center experience

BackgroundTo evaluate the effect of reconstruction and repair, using a mini-plate and bone graft for HIV -positive patients with giant cell tumor of long bone.MethodsWe conducted a retrospective analysis of 12 HIV positive patients with giant cell tumor of long bone. A non-HIV-positive cohort of patients, matched for age, sex, and disease type, was selected as the control group. From June 2012 to August 2020, curettage by ultrasonic scalpel was performed in all patients, combined with min- plate and bone graft treatment. All patients were followed- up for 18 to 60 months. Limb function was evaluated, using the MSTS93 scoring system, and any examples of postoperative recurrence, distant metastasis, complications, MSTS93 score, and fracture prognosis were recorded.ResultsThe mean age of HIV group was 43.5 years. The ratio of men to women was 11: 1. In all cases the histopathological diagnosis was clear, except the patients with primary malignant giant cell tumor of bone, including five, three, two, and two cases in the proximal tibia, distal femur, distal tibia, and talus, respectively. Following their surgery, all patients were followed up with an average of 31.24 ± 11.84 months. No local recurrence or pulmonary metastases were observed. Post-surgery, all the 12 patients showed good bone morphologic repair and reconstruction, good bone healing, good joint function, and no pathological fractures around their lesion. In the HIV group, one case of giant cell tumor in the proximal tibia showed mild articular surface collapse and mild valgus deformity of the knee joint but retained good joint function. The MSTS scores of excellent or good in the two groups comprised 83.3%, thus, there was no significant difference between them (P > 0.05). Compared with preoperatively, the MSTS scores in the HIV group were significantly improved, ranging from 7 to 11 points preoperatively to 24 to 27 points postoperatively; this difference was statistically significant (P < 0.05).ConclusionReconstruction and repair, using a mini-plate and bone graft for HIV -positive patients with giant cell tumor of long bone can achieve satisfactory results. The mini- plate requires little space and is flexible during reconstruction and fixation, significantly reducing complications such as surgical site infection, as well as preserving joint function and avoiding amputation; therefore, it is a safe and effective treatment method.

THE RESULTS OF TREATMENT OF GIANT CELL TUMOR OF LONG BONES WITH DENOSUMAB

Surgical intervention remains a gold standard for the treatment of giant cell tumors (GCT) of long bones. The significant risk of recurrence after the curettage and a high complication rate after radical resections is still an unsolved problem. Targeted therapy with denosumab could solve this problem in favor of curettage, but recent studies have shown negative results with denosumab in such situation. Objective. To analyze the results of the denosumab application in patients with long bone GCP with indications for joint salvage surgery. Methods. We compared the treatment results in two groupsof patients: 1st retrospective (control) group — 57 patients, who underwent curettage with surgical treatment and the 2nd prospective (main) group — 42 patients with combination of surgery with neoadjuvant and adjuvant denosumab tretment. In the 2nd group of patients received 5 neoadjuvant and 5 adjuvant cycles of denosumab. The median follow-up period was 189 months in the control group, and 45 months in the main group. Results. Disease progression which identified as a local recurrence was revealed in the control group in 15 patients (25.4 %) and in 7 patients (16.7 %) in the maingroup (p = 0.19). In the main group, the median time to relapse was 19.8 months (8–34 months) from the date of surgery, in the control group — 15.1 months (9–28 months), respectively. The statistically significant difference in relapse-free survival (RFS) between patients in the main group and in the control group (p = 0.18) was not revealed. But the 5-year RFS in the main group was higher and reached to 85 % (95 % CI 74–96 %) versus 75 % (95 % CI 64–86 %) in control group, respectively. There was no evidence of malignant transformation in the main group and one case in retrospective group. Conclusions. The application of denosumab in the regimen before and after curettage is associated with lees number of relapses — 16.7 % vs. 25.4 % without denosumab, respectively. The lack of statistically significant difference between groups does not provide the sufficient reasons for denosumab prescription in neoadjuvant regimen. But adjuvant administration of denosumab can be considered as preventing factor of recurrence after primary tumor curettage, which may be perspective for further study and optimization of indications for its application in patients with GCT.

Diagnostic Value of CT- and MRI-Based Texture Analysis and Imaging Findings for Grading Cartilaginous Tumors in Long Bones.

ObjectiveTo confirm the diagnostic performance of computed tomography (CT)-based texture analysis (CTTA) and magnetic resonance imaging (MRI)-based texture analysis for grading cartilaginous tumors in long bones and to compare these findings to radiological features.Materials and MethodsTwenty-nine patients with enchondromas, 20 with low-grade chondrosarcomas and 16 with high-grade chondrosarcomas were included retrospectively. Clinical and radiological information and 9 histogram features extracted from CT, T1WI, and T2WI were evaluated. Binary logistic regression analysis was performed to determine predictive factors for grading cartilaginous tumors and to establish diagnostic models. Another 26 patients were included to validate each model. Receiver operating characteristic (ROC) curves were generated, and accuracy rate, sensitivity, specificity and positive/negative predictive values (PPV/NPV) were calculated.ResultsOn imaging, endosteal scalloping, cortical destruction and calcification shape were predictive for grading cartilaginous tumors. For texture analysis, variance, mean, perc.01%, perc.10%, perc.99% and kurtosis were extracted after multivariate analysis. To differentiate benign cartilaginous tumors from low-grade chondrosarcomas, the imaging features model reached the highest accuracy rate (83.7%) and AUC (0.841), with a sensitivity of 75% and specificity of 93.1%. The CTTA feature model best distinguished low-grade and high-grade chondrosarcomas, with accuracies of 71.9%, and 80% in the training and validation groups, respectively; T1-TA and T2-TA could not distinguish them well. We found that the imaging feature model best differentiated benign and malignant cartilaginous tumors, with an accuracy rate of 89.2%, followed by the T1-TA feature model (80.4%).ConclusionsThe imaging feature model and CTTA- or MRI-based texture analysis have the potential to differentiate cartilaginous tumors in long bones by grade. MRI-based texture analysis failed to grade chondrosarcomas.