Aykut Çeli̇k

This study aims to compare the biomechanical performance of three different surgical fixation techniques in the treatment of proximal humerus fractures with medial metaphyseal defects. A total of 24 synthetic humerus bone models were used and equally divided into three groups (n = 8 per group). A standardized unstable proximal humerus fracture model with a medial metaphyseal cortical defect extending to the surgical neck was created using a three-dimensional (3D)-printed osteotomy guide. Group 1 received fixation with a lateral anatomical locking plate. Group 2 was treated with a combination of a lateral anatomical plate and a medial buttress plate (dual plating). Group 3 underwent fixation with an intramedullary nail (IMN); in this group, four specimens had distal locking with an endopin (Group 3a), and the other four with static screws (Group 3b). All specimens were subjected to axial loading until failure. Forces at the onset of failure and complete failure were recorded, and fracture patterns were documented. In Groups 1 and 2, transverse fractures consistently occurred at the level of the most distal screw of the lateral plate. In Group 3, failure was observed either proximally or distally at the nail tip, including butterfly fragment formation and metaphyseal collapse. Group 2 exhibited the highest resistance to axial loading, followed by Group 1 and Group 3, with statistically significant differences between all groups (p = 0.043, p = 0.0003, p < 0.00001). No significant difference was found between subgroups 3a and 3b (p > 0.05). Our study results indicate that double plating provides the greatest axial stability in proximal humerus fractures with medial metaphyseal defects, supporting its use in fracture patterns with medial column deficiency. However, as fixation choice should be guided by patient-specific factors and surgical feasibility, these findings should be interpreted in the context of experimental conditions and loading limitations.

Aim: The aim of this study is to evaluate the causative agents, diagnosis, treatment, and outcomes of acute septic arthritis cases. Material and Methods: In this retrospective, single-center study, patients over 18 years of age diagnosed with acute septic arthritis were searched from the hospital database between January 2015 and April 2021. Demographic characteristics, diagnostic procedures, therapeutic management, and outcomes were recorded. Results: A total of 59 patients and 60 septic joints were included in the study. The causative microorganisms were isolated in 52.54% of the cases. Staphylococcus aureus grew in 70.96% of the cases and among these, 31.82% were methicillin-resistant. The most frequently affected body part was the knee (73.33%). The cases were found to have fever at a rate of 42.37%. Diabetes was the most common comorbidity (30.51%), and immunosuppression was found in 39% of the cases. Arthrotomy was the most commonly used surgical method for the management of septic arthritis (43.55%). The mortality rate was 6.78%. The cases were categorized as groups with and without microorganisms isolated in culture. When these two groups were compared, no statistically significant difference was found except for the duration of hospitalization (p=0.001). Conclusion: Septic arthritis should be considered in the differential diagnoses of a warm and swollen single joint, especially in the presence of risk factors, until it is excluded. Knowledge of regional epidemiological data is essential in planning treatment approaches.

Aim: The grade of the tumor is essential for planning the treatment strategy in soft-tissue sarcomas (STS). The goal of this study is to determine magnetic resonance imaging features related to histopathological grade and aggressiveness of STS. Material and Method: This retrospective single-center study involved preoperative contrast-enhanced MRI examinations of 64 patients with STS. MRI findings evaluated were; heterogeneity, necrosis, hemorrhage, and relationship with surrounding tissue in T1-weighted (T1W), T2-weighted (T2W), and T1W post-contrast sequences of the lesion. Histological grade was determined with the Fédération Nationale des Centres de Lutte Contre Le Cancer (FNCLCC) grading system, and the aggressiveness of the lesion was measured with the Ki-67 index. Results: Sixty-four patients (mean age 45.5±21.6, M/F ratio 34/30) with STS were included. 33 (51.6%) patients graded as FNCLCC grade 3. On MRI examinations, the absence of necrosis was significantly associated with FNCLCC grade 1 and a low Ki-67 index (p

Background and Objectives: Tenosynovial giant cell tumors (TSGCTs) are benign soft tissue tumors that are divided into localized- and diffuse-type tumors, according to the World Health Organization classification of soft tissue tumours. The diffuse-type TSGCT sometimes behave aggressively and poses treatment challenges especially in patients with neurovascular involvement. Symptomatic patients who are not good candidates for surgery due to high morbidity risk may benefit from medical therapy. Objectives: Drugs that target programmed death ligand 1 (PD-L1) are among a new generation of medical therapy options, which, recently, have been explored and have displayed promising results in various cancer types; therefore, we aimed to investigate the PD-L1 status of TSGCTs as a possible therapeutic target. Materials and Methods: We assessed the PD-L1 status of 20 patients (15 men and 5 women, median age = 39 years) that had been diagnosed with TSGCTs in a single institution, between 2018 and 2020. The patients had localized- (n = 7) and diffuse-type (n = 13) TSGCTs. Formalin-fixed paraffin-embedded (FFPE) blocks were retrospectively retrieved from the pathology department. An immunohistochemical analysis was performed in sections of 3 micron thickness from these blocks. Results: Seventy-five percent of our patients with TSGCTs were immunopositive to PD-L1 staining. Conclusions: Taking into consideration the high positivity rate of PD-L1 staining in TSGCTs, PD-L1 blockage may be used as a valuable medical treatment for TSGCTs; however, further studies are needed.

Aim: Spindle cell lipoma is a rare tumor. Although located subcutaneously, they are localized in the posterior neck, shoulder, and lumbar regions. It can radiologically mimic liposarcoma. It is important to differentiate spindle cell lipoma from atypical lipomatous tumors. In this study, we aimed to present our studies on our patients with spindle cell lipoma with histopathological and clinical findings and give brief information about the differential diagnosis of this rare lipomatous lesion. Material and Methods: A total of 29 patients (27 male, 2 female) who underwent surgical treatment for spindle cell lipoma between January 2015 and December 2020 were included in this retrospective study. All patients were presented with mass lesions, and preoperative biopsy was performed in cases with low-fat content mass lesions. Results: The mean age of the patients was 57.0±14.6 (range, 25-79) years and the mean follow-up period was 25.0±8.6 (range, 6-47) months. No additional disease was detected in the patients. Marginal resection was preferred in 5 (17.2%) patients with lesions close to neurovascular structures. Wide resection was performed in the other 24 (82.8%) patients. CD34 was positive in all lesions. In one patient, CDK4 was positive, and the diagnosis was made as atypical spindle cell lipoma. At the last follow-up, there was no complication and recurrence in any of the cases. Conclusion: Spindle cell lipomas should be regarded in the differential diagnosis of lipomatous tumors. Local excision with negative margins may prevent a recurrence. Correct histopathologic differentiation from liposarcoma is of paramount importance for appropriate treatment.