A novel H-shaped miniplate (HSM) was specifically designed for restorative laminoplasties to restore patients’ posterior elements after laminectomies. A validated finite element (FE) model of L2/4 was utilized to create a laminectomy model, as well as three restorative laminoplasty models based on the fixation of different miniplates after a laminectomy (the RL-HSM model, the RL-LSM model, and the RL-THM model). The biomechanical effects of motion and displacement on a laminectomy and restorative laminoplasty with three different shapes for the fixation of miniplates were compared under the same mechanical conditions. This study aimed to validate the biomechanical stability, efficacy, and feasibility of a restorative laminoplasty with the fixation of miniplates post laminectomy. The laminectomy model demonstrated the greatest increase in motion and displacement, especially in axial rotation, followed by extension, flexion, and lateral bending. The restorative laminoplasty was exceptional in preserving the motion and displacement of surgical segments when compared to the intact state. This preservation was particularly evident in lateral bending and flexion/extension, with a slight maintenance efficacy observed in axial rotation. Compared to the laminectomy model, the restorative laminoplasties with the investigated miniplates demonstrated a motion-limiting effect for all directions and resulted in excellent stability levels under axial rotation and flexion/extension. The greatest reduction in motion and displacement was observed in the RL-HSM model, followed by the RL-LSM model and then the RL-THM model. When comparing the fixation of different miniplates in restorative laminoplasties, the HSMs were found to be superior to the LSMs and THMs in maintaining postoperative stability, particularly in axial rotation. The evidence suggests that a restorative laminoplasty with the fixation of miniplates is more effective than a conventional laminectomy due to the biomechanical effects of restoring posterior elements, which helps patients regain motion and limit load displacement responses in the spine after surgery, especially in axial rotation and flexion/extension. Additionally, our evaluation in this research study could benefit from further research and provide a methodological and modeling basis for the design and optimization of restorative laminoplasties.
The effects of 4-phenylbutyrate (4-PBA) on particle-induced macrophage apoptosis in vitro have not been previously documented. This study aims to investigate the thera-peutic potential of 4-PBA in alleviating titanium nanoparticle (TiNP)-induced in-flammatory injury mediated by macrophages. Our findings demonstrate that TiNPs exhibit specific properties capable of inciting inflammatory injury to macrophages. Furthermore, the extent of inflammatory injury inflicted by TiNPs on macrophages progressively increases in correlation with both the concentration of particles and du-ration of exposure. Exposure to TiNPs significantly reduces macrophage viability, promotes apoptosis, enhances the expression of inflammatory cytokines, and exacer-bates the production of reactive oxygen species (ROS). Co-treatment with 4-PBA sig-nificantly alleviates the severity of particle-induced inflammatory injury while simul-taneously facilitating apoptosis in stressed macrophages. Pharmacological intervention with 4-PBA facilitates TiNP-induced macrophage apoptosis by increasing the expres-sion of pro-apoptotic proteins such as Caspase-3 and Bax, while decreasing the levels of anti-apoptotic protein Bcl-2. When used as an independent treatment, 4-PBA does not provoke a pronounced inflammatory response nor induce significant changes in mac-rophage apoptosis, underscoring its potential as a safe therapeutic option. These find-ings substantiate the hypothesis that employing a specific approach to facilitate mac-rophage apoptosis could serve as an effective therapeutic strategy for managing aseptic loosening. Significantly, this approach demonstrates a favorable safety profile, posi-tioning it as a promising avenue for future clinical applications in this domain.