Objective To explore the expressions of bone morphogenetic protein 2 (BMP-2) and runt-related transcription facotr 2 (Runx2) and microarchitecture of trabecular bone periacetabula in adult patients with developmental dysplasia of the hip (DDH). Methods Between March and September 2008, the trabecular bone periacetabulum was collected from 8 patients with DDH who were scheduled for total hip arthroplasty (aged 37-55 years, 3 males and 5 females, trial group) and from 8 patients with avascular necrosis of the femoral head (Ficat stage II) who were scheduled for hip resurfacing arthroplasty (aged 36-55 years, 3 males and 5 females, control group). The expressions of BMP-2 and Runx2 in the trabecular bone were determined by real-time quantitative PCR, and the microarchitecture was observed by micro-CT and the following parameters were determined: bone volume/total volume (BV/TV), connectivity density (Conn.Dens), trabecular number (Tb. N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), and structure model index (SMI). Results The expressions of BMP-2 and Runx2 were significantly lower in trial group than in control group (P lt; 0.05). The micro-CT showed sparse trabecular bone in trial group and dense trabecular bone in control group. BV/TV and Tb.N in trial group were significantly lower than those in control group, and SMI and Tb.Sp in trial group were significantly higher than those in control group (P lt; 0.05); there was no significant difference in Conn.Dens and Tb.Th between 2 groups (P gt; 0.05). Conclusion The trabecular bone is in a low metabolism condition and its microarchitecture is tendency to be osteoporosis trabecualr bone in adult patients with DDH. It may be related with the acetabular component loosening after total hip arthroplasty.
ObjectiveTo review the methods of improving the mechanical properties of hydrogels and the research progress in bone tissue engineering. MethodsThe recent domestic and foreign literature on hydrogels in bone tissue engineering was reviewed, and the methods of improving the mechanical properties of hydrogels and the effect of bone repair in vivo and in vitro were summarized. ResultsHydrogels are widely used in bone tissue engineering, but their mechanical properties are poor. Improving the mechanical properties of hydrogels can enhance bone repair. The methods of improving the mechanical properties of hydrogels include the construction of dual network structures, inorganic nanoparticle composites, introduction of conductive materials, and fiber network reinforcement. These methods can improve the mechanical properties of hydrogels to various degrees while also demonstrating a significant bone repair impact. ConclusionThe mechanical properties of hydrogels can be effectively improved by modifying the system, components, and fiber structure, and bone repair can be effectively promoted.