Intramedullary nailing versus plate compound osteosynthesis in subtrochanteric and diaphyseal pathologic femoral fractures: a retrospective cohort study.

PURPOSE: Pathologic fractures of the extremities due to carcinoma metastases require individual and patient prognosis-related stabilization procedures. Quick remobilization of the patient to restore the quality of life is of high importance, especially in the case of subtrochanteric and diaphyseal femoral fractures. In our retrospective cohort study, we evaluated intraoperative blood loss, length of operation, complication rate, and regain of lower extremity function in plate compound osteosynthesis (PCO) versus intramedullary nailing (IM) for subtrochanteric and diaphyseal pathologic fractures of the femur. METHODS: Between January 2010 and July 2021, we retrospectively reviewed 49 patients who were treated at our institution for pathologic fractures of the subtrochanteric and diaphyseal femurs for group differences in terms of blood loss, length of operation, implant survival, and Musculoskeletal Tumor Society (MSTS) score. RESULTS: We included 49 stabilization procedures of the lower extremity due to pathologic fractures of the proximal or diaphyseal femur, with a mean follow-up of 17.7 months. IM (n = 29) had a significantly shorter operation time than PCO (n = 20) (112.4 ± 9.4 and 163.3 ± 15.96 min, respectively). We did not detect any significant differences in terms of blood loss, complication rate, implant survival, or MSTS score. CONCLUSION: Based on our data, pathologic subtrochanteric and diaphyseal fractures of the femur can be stabilized with IM, which has a shorter operation time than PCO, but the complication rate, implant survival, and blood loss remain unaffected.

Intramedullary Nailing Versus Compound Plate Osteosynthesis in Pathologic Diaphyseal Humerus Fractures: A Retrospective Cohort Study.

BACKGROUND AND OBJECTIVES: Pathologic fractures of the extremities due to carcinoma metastases require individual and patient prognosis-related stabilization procedures. Considering the anatomic features of the humerus, implant material stability is less critical than femoral fractures because of less weight-bearing stress. Therefore, operation length, blood loss, and quick recovery of function are of greater interest. In this retrospective cohort study, we evaluated and compared the outcomes of compound plate osteosynthesis and intramedullary (IM) nailing while managing diaphyseal pathologic fractures of the humerus. METHODS: We retrospectively reviewed patients treated at our institution for pathologic fractures of the diaphyseal humerus between 2010 and 2021 for group differences (plate osteosynthesis vs. IM nailing) in terms of blood loss, length of operation, implant survival, and upper extremity function. RESULTS: We reviewed 42 stabilization procedures due to pathologic diaphyseal humerus fractures, with a mean follow-up of 8.5±15.4  months. IM nailing (n=20) showed a significantly lower blood loss (266.7±23.7 mL) than plate osteosynthesis (n=22, 571.1±92.6 mL). We did not detect statistically significant differences in the complication rate, length of operation, or Musculoskeletal Tumor Society score. CONCLUSION: Our findings suggested that diaphyseal fractures of the humerus should be stabilized using an IM nail rather than plate osteosynthesis due to lower blood loss, while complication rate, implant survival, and length of operation remain indifferent.

Protective effects of rituximab on puromycin-induced apoptosis, loss of adhesion and cytoskeletal alterations in human podocytes.

Podocytes are highly specialized cells playing a key role in the filtration function of the kidney. A damaged podocyte ultrastructure is associated with a reorganization of the actin cytoskeleton and accompanied with a loss of adhesion to the glomerular basement membrane leading to proteinuria in many forms of glomerular diseases, e.g. nephrotic syndrome. If the first-line therapy with glucocorticoids fails, alternative immunosuppressive agents are used, which are known to have the potential to stabilize the actin cytoskeleton. A new option for preventing relapses in steroid dependent nephrotic syndrome is the monoclonal antibody rituximab, which, in addition to its B-cell depleting effect, is assumed to have direct effects on podocytes. We here provide data on the non-immunological off-target effects of the immunosuppressant rituximab on podocyte structure and dynamics in an in vitro puromycin aminonucleoside model of podocyte injury. A conditionally immortalized human podocyte cell line was used. Differentiated podocytes were treated with puromycin aminonucleoside and rituximab. Our studies focussed on analyzing the structure of the actin cytoskeleton, cellular adhesion and apoptosis using immunofluorescence staining and protein biochemistry methods. Treatment with rituximab resulted in a stabilization of podocyte actin stress fibers in the puromycin aminonucleoside model, leading to an improvement in cell adhesion. A lower apoptosis rate was observed after parallel treatment with puromycin aminonucleoside and rituximab visualized by reduced nuclear fragmentation. Consistent with this data, Western-blot analyses demonstrated that rituximab directly affects the caspase pathways by inhibiting the activation of Caspases-8, -9 and -3, suggesting that rituximab may inhibit apoptosis. In conclusion, our results indicate an important role of the immunosuppressant rituximab in terms of stability and morphogenesis of podocytes, involving apoptosis pathways. This could help to improve therapeutical concepts for patients with proteinuria mediated by diseased podocytes.