Numerical investigation of the effect of bone cement porosity on osteoporotic femoral augmentation

Advances in materials-based therapeutic strategies against osteoporosis

Osteoporosis is caused by the disruption in homeostasis between bone formation and bone resorption. Conventional management of osteoporosis involves systematic drug administration and hormonal therapy. These treatment strategies have limited curative efficacy and multiple adverse effects. Biomaterials-based therapeutic strategies have recently emerged as promising alternatives for the treatment of osteoporosis. The present review summarizes the current status of biomaterials designed for managing osteoporosis. The advantages of biomaterials-based strategies over conventional systematic drug treatment are presented. Different anti-osteoporotic delivery systems are concisely addressed. These materials include injectable hydrogels and nanoparticles, as well as anti-osteoporotic bone tissue engineering materials. Fabrication techniques such as 3D printing, electrostatic spinning and artificial intelligence are appraised in the context of how the use of these adjunctive techniques may improve treatment efficacy. The limitations of existing biomaterials are critically analyzed, together with deliberation of the future directions in biomaterials-based therapies. The latter include discussion on the use of combination strategies to enhance therapeutic efficacy in the osteoporosis niche.

Study on the angiogenesis ability of Polymethyl methacrylate-mineralized collagen/Mg-Ca composite material in vitro and the bone formation effect in vivo

Magnesium (Mg) and its alloys show high degrees of biocompatibility and biodegradability, used as biodegrad able materials in biomedical applications. In this study, Polymethyl methacrylate (PMMA) - mineralized collagen (nano-Hydroxyapatite/collagen; nHAC)/Mg-Ca composite materials were prepared, to study the angiogenesis ability of its composite materials on Human umbilical vein endothelial cells (HUVECs) and its osteogenesis effect in vivo. The results showed that the PMMA-nHAC reinforcement materials can promote the proliferation and adhesion in HUVECs of Mg matrix significantly, it can enhance the migration motility and VEGF expression of HUVECs. In vivo, Micro-CT examination showed that with coated samples presenting the highest bone formation. Histologically, the materials and their corrosion products caused no systematic or local cytotoxicological effects. Therefore, the Mg matrix composites prepared in the present study has good biocompatibility and PMMA-nHAC/Mg-Ca composite may be an ideal orthopedic material to improve the bone formation, and biodegradable magnesium based implants with bioactivity have potential applications in bone tissue.

Biomechanical role of osteoporosis in the vibration characteristics of human spine after lumbar interbody fusion

Lumbar vertebrae osteoporosis is the most common challenge for lumbar interbody fusion, and this challenge has been widely concerned by scholars for many years. However, under whole-body vibration, osteoporosis how to affect the vibration characteristics of the fusion lumbar spine, complications, and fusion outcomes is urgent to know. The L1-L5 finite element model of lumbar spine was modified to simulate the transforaminal lumbar interbody fusion model with the bilateral pedicle screw fixator at L4-L5 level. A 5 Hz, 40 N sinusoidal vertical load supplemented with a 400 N preload was used to simulate the vertical vibration of human body. The results showed that under whole-body vibration, osteoporosis of fused vertebrae may cause the adjacent segments more unstable and increase the risk of adjacent segment diseases, subsidence, cage failure, rod failure, and lumbar instability. Osteoporosis of the fused vertebrae may cause the vertebral cells an unstable, inhibited growth and lead to poorer fusion outcomes. The findings may assist us in understanding the effect of osteoporosis on the vibration characteristics of lumbar spine fusion and provide references to clinical treatments for lumbar interbody fusion and lumbar vertebrae osteoporosis.