Introduction: The treatment of malignant tumors in the shoulder region is exceptionally complex due to its anatomical specificity. Modern approaches involve extensive tumor resection and the application of adjuvant oncological therapy. After the resection of these tumors, large soft tissue defects often remain, requiring extensive reconstructive procedures. Adequate reconstruction of these defects is of invaluable clinical importance as it allows for the safe achievement of planned resection margins and provides the opportunity to quickly apply adjuvant oncological therapy. Materials and Methods: This study included 6 patients (2 women and 4 men) treated at the Institute for Orthopedics “Banjica”, from January 2021 to February 2024. Patients were pathohistologically diagnosed with primary tumors and metastases in the shoulder region. For the reconstruction of the defect, a pedicled trapezius musculocutaneous flap was used. Results: The immediate postoperative results were satisfactory. In two cases healing at the donor site was delayed. There were no local recurrences of tumor during the follow-up period. All musculocutaneous flaps were vital. Satisfactory functional and aesthetic results were achieved. Discussion and Conclusion: The use of pedicle musculocutaneous flaps allows the achievement of safe, wide resection margins without complications arising from insufficient coverage of the resultant soft tissue defects. The trapezius muscle is almost ideal for covering defects on the shoulder, as the muscle itself is relatively small but carries a significant skin envelope that is sufficient to close medium, and even some larger, defects. Moreover, this spares the latissimus dorsi muscle, which could be utilized in case of recurrence.

Periprosthetic pathological fractures, especially those caused by metastases to bone tissue, are a complex challenge in orthopedic practice. This retrospective case series showcases three patients with metastatic pathological fractures who previously had endoprostheses implanted. The increasing incidence of these fractures corresponds with the rising number of alloarthroplastic surgeries, the younger population undergoing these procedures, and the growing prevalence of cancer.

The cases of three patients with different types of fractures are described, following a detailed analysis of clinical presentation, characteristics of primary tumors, and choice of surgical techniques. In the first case, a 62-year-old patient with a "Vancouver C" type femur fracture, from renal carcinoma metastasis, underwent a successful treatment using hybrid stabilization, a retrograde nail and plate along with cement augmentation. The second case involved an 80-year-old patient with a "Lewis and Rorabeck" type A tibial fracture due to renal carcinoma metastasis, stabilized with an intramedullary nail and cement augmentation. The third case describes a 73-year-old patient with a "Vancouver" B2 femur fracture from breast cancer metastasis, treated by resecting the proximal femur and implanting a resection prosthesis.

This case series underscores the need for personalized treatment strategies for periprosthetic pathological fractures, taking into account the specifics of the primary tumor, fracture location, and the patient's overall health. Given the absence of definitive guidelines, a team-based approach is essential, blending conservative and surgical techniques to ensure the best possible outcomes. This approach involves careful consideration of the patient's health status, expected lifespan, and specific needs.

The most frequent malignant bone tumor, osteosarcoma (OS), has a strong propensity for local invasion and early metastasis. Unfortunately, the prognosis has not improved in cases of metastasis or recurrence, despite the fact that individuals with localized OS currently live longer. Because there are currently few specialist treatments for OS metastatic biology, more biologically intelligent anti-cancer strategies must be used. β - Caryophyllene (BCP) is a naturally compound in plants. Various studies have shown that BCP has significant anti-cancer effects on different cancer. However, there is currently no research exploring the therapeutic effect of BCP on OS. Therefore, this study explores the anti-tumor effect of BCP on OS and its mechanism of action. The expression of the PPAR-γ and Hippo-YAP signaling pathway, as well as the levels of ROS and apoptosis and invasion ability, of osteosarcoma were found after cultured osteosarcoma MG-63, U2OS, and HOS cell lines using BCP media containing varying quantities for a duration of 24 hours. Moreover, inoculate HOS cells subcutaneously in mice and inject different doses of BCP for 21 days. Observe tumor size, apoptosis level, and PPAR-γ and Hippo-YAP signaling pathway expression. In vitro, BCP increased the level of ROS, induced apoptosis, inhibited their migration and invasion ability, and upregulated PPAR-γ expression level and inhibition of Hippo-YAP pathway expression in OS cells. In vivo, BCP restricted the size of OS and promoted tumor cell apoptosis. Research has confirmed that BCP inhibits the proliferation and invasion of OS by regulating the PPAR-γ and Hippo-YAP signaling pathways.

The diagnosis of musculoskeletal tumors is a complex process that requires a systematic approach for accurate diagnosis and appropriate treatment planning. The initial steps include a properly taken medical history and a detailed clinical examination to determine the symptoms and localization of the tumor. Radiography of the affected bone is usually the first diagnostic procedure, providing basic information about the bone tissue. Computerized tomography (CT) allows for a more detailed evaluation of bone lesions and the assessment of systemic tumor spread. Magnetic resonance imaging (MRI) provides superior soft tissue resolution, facilitating precise tumor localization and assessment of nerve and vascular tissue involvement. Whole-body scans, such as scintigraphy and PET scanning, are crucial for detecting metastases and assessing the disease stage. Biopsy, as the final procedure in the series, is considered the gold standard in definitive diagnosis, providing histological information about the type and malignancy of the tumor.

This diagnostic approach precisely determines the characteristics and stage of musculoskeletal system tumors, enabling appropriate treatment planning and better outcomes for patients.

Axillary soft tissue sarcoma (STS) is challenging due to its proximity to vital neurovascular bundles. We conducted a prospective, observational, pilot study to explore whether 3D multimodality imaging (3DMMI) can improve preoperative planning for and surgical outcomes of patients with axillary STS. Twenty-one patients with STS (diameter >5 cm) of the axilla were allocated, at their discretion, to either a control group undergoing traditional preoperative planning with separate computed tomography angiography, magnetic resonance imaging, and magnetic resonance neurography, or an intervention group where 3DMMI, digitally created based on these images, revealed the tumour, adjacent skeletomuscular and neurovascular structures in three dimensions. Primary outcome measures were surgical margins and surgical complications. Secondary outcomes included operative time, blood loss, serum C-reactive protein and interleukin-6, length of hospital stay, and limb function. The 3DMMI group had a lower, although not significantly different, inadvertent positive margin rate (1/12 vs. 3/9, P=0.272), significantly shorter operative time (P=0.048), reduced blood loss (P=0.038), and reduced length of hospital stay (P=0.046). This endorses larger trials, aiming to improve complex surgical procedures and how preoperative planning could be performed in the future.