Silver (Ag) has broad-spectrum antibacterial properties and is widely used in various fields, including in antibacterial coatings for orthopedic implants. For reasons of cost and cytotoxicity, improvement of the antibacterial efficiency of Ag is necessary. The scientific community has also shown a strong enthusiasm in this research area. In this paper, ZnO nanorod arrays were prepared on a titanium (Ti) substrate by seed-assisted hydrothermal method and Ag nanoparticles were deposited by magnetron sputtering to obtain Ag nanoparticle-decorated ZnO nanorod arrays (ZnO nanorods/Ag nanoparticles). The antibacterial properties of ZnO nanorods/Ag nanoparticles against Pseudomonas aeruginosa were systematically studied by agar diffusion method and were compared with other samples such as ZnO nanorod arrays and ZnO seed layer/Ag nanoparticles. The experimental results showed that ZnO nanorods/Ag nanoparticles displayed significantly higher antibacterial properties against Pseudomonas aeruginosa than other samples, including ZnO nanorod arrays and ZnO seed layer/Ag nanoparticles. These superior antibacterial properties originated predominantly from the morphological structure of ZnO nanorods, which optimized the particle size and distribution of Ag nanoparticles, greatly improving their antimicrobial efficiency. The synergistic antibacterial properties of Ag nanoparticles and ZnO nanorods make Ag nanoparticle-decorated ZnO nanorod arrays a promising candidate for antibacterial coating of orthopedic implants.

Previous articles reported on the tip–apex distance, lag screw placement, fracture pattern, reduction quality, osteoporosis and other factors associated with second surgery. The current study focused on investigating the association of the matching degree between proximal femoral intramedullary nail and femoral medullary cavity on reoperation rate. A retrospective cohort study was conducted. It included patients with intertrochanteric fracture who were treated with proximal femoral anti-rotatory intramedullary nail (PFNA) between January 2016 and April 2021. The gap between the intramedullary nail and the femoral medullary cavity was equal to the difference in diameter between the two. According to the gap size, all patients were divided into three groups, as follows: high-matching group: gap ≤ 2 mm; middle-matching group: 2 < gap < 4 mm; and low-matching group: gap ≥ 4 mm. The mean gap was measured through standard images. The primary observational index was whether the reoperation was needed, and secondary observational indexes included operative time, length of hospital stay. Patient characteristics were recorded, as follows: age, sex, follow-up time, fracture pattern, reduction grade and length of intramedullary nail. A total of 203 eligible patients were recorded, including 78 males (38.4%) and 125 females (61.6%). They had a mean age of 77.8 ± 9.9 years old and an average follow-up time of 58.1 ± 24.0 weeks. Twenty-seven patients (13.3%) needed a second operation. Coxa varus combined with screw cutting was the most common reason for reoperation (11 cases). Unstable fracture pattern with poor reduction grade tended to contribute to reoperation, whose odds ratio (OR) was 6.61 (95% confidence interval [CI], 1.98–22.09; P = 0.002). The three groups had 11 cases (13.7%), 12 cases (13.8%) and 4 cases (11.1%) of reoperation, respectively, and logistic regression showed no significant association was noted between matching degree of intramedullary nail and reoperation rate. The matching degree between proximal femoral intramedullary nail and femoral medullary cavity did not seem to be an important factor for reoperation, which offered more options of intramedullary nail size intraoperatively and reduced implants stock from inventory.

Numerous studies have addressed the use of vancomycin (VA) to effectively treat bacterial infections. However, VA is known to cause side effects when administered intravenously. Herein, monodisperse poly( N -isopropylacrylamide) (PNIPAAm) hollow nanocapsules were synthesized at the interface of a water-in-oil (W/O) single emulsion via Shirasu porous glass (SPG) membrane emulsification and UV-initiated polymerization. In water solutions, the PNIPAAm nanocapsules were able to encapsulate VA and form a new nanoscale water-soluble drug delivery system, namely, PNIPAAm-VA. In vitro experiments showed that PNIPAAm and PNIPAAm-VA had no cytotoxicity toward human bone marrow mesenchymal stem cells. In addition, the slow hydrolysis of PNIPAAm-VA in vitro led to the progressive release of VA, which was discharged at more than 50% and 80% of its initial concentration within 10 days at 37°C and 40°C, respectively; this subsequently inhibited the growth of methicillin-resistant Staphylococcus aureus bacteria. We believe that our PNIPAAm-VA nanoparticles can potentially be used as an effective injectable for temperature-sensitive materials in vivo to achieve the localized controlled release of drugs as safe and specific therapeutic agents.