Robot-assisted total hip arthroplasty (THA) has the potential of improving cup positioning. However, there is an associated learning curve with robot. This study aimed to determine one surgeon's learning curve with robot-assisted THA and whether robot could achieve similar accuracy in cup positioning as manual THA. The first 100 robot-assisted THA operated by one experienced surgeon on manual THA was respectively reviewed. The operating time and robotic complications were recorded to calculate the learning curve through cumulative summation analysis. The demographics, operating time, cup positioning, leg length discrepancy, hip offset, robotic complications and hip Harris score between proficient robot-assisted THA and manual THA in the same period were also compared. The average operating time of robot-assisted THA was 95.92 ± 15.64 min, ranging from 68 to 145 min. Robot-assisted THA was associated with a learning curve of 14 cases for operating time. The duration of acetabular registration and cup implantation between two phases (1-14 and 15-100 case) had significant differences. There were 92% proficient robot-assisted THA and 82% manual THA respectively locating within the Lewinnek's safe zone. The variation of inclinations in proficient robot-assisted THA was significantly less than that in manual THA. In the surgeon's series, it took 14 cases' learning curve to be proficient in robot-assisted THA. In the proficiency phase, robot had an advantage in cup positioning than manual technique.

Human joints move thousands of times a day. The articular cartilage plays a vital role in joints’ protection. If there is dysfunction in cartilage lubrication, cartilage cannot maintain its normal function. Eventually, the dysfunction may bring about osteoarthritis (OA). Extensive researches have shown that fluid film lubrication, boundary lubrication, and hydration lubrication are three discovered lubrication models at cartilage surface, and analyzing and simulating the mechanism of cartilage lubrication are fundamental to the treatment of OA. This essay concludes recent researches on the progress of cartilage lubrication and biomimetic cartilage, revealing the pathophysiology of cartilage lubrication and updating bio-inspired cartilage lubrication applications.

Rheumatoid Arthritis is a universal disease that severely affects the normal function of human joints and the quality of life. Millions of people around the world are diagnosed with rheumatoid arthritis every year, carrying a substantial burden for both the individual and society. Hydrogel is a polymer material with good mechanical properties and biocompatibility, which shows great potential in the treatment of rheumatoid arthritis. With the progress of tissue engineering and biomedical material technology in recent years, more and more studies focus on the application of hydrogels in rheumatoid arthritis. We reviewed the progress of hydrogels applied in rheumatoid arthritis in recent years. Also, the needed comprehensive performance and current applications of therapeutic hydrogels based on the complex pathophysiological characteristics of rheumatoid arthritis are also concluded. Additionally, we proposed the challenges and difficulties in the application of hydrogels in rheumatoid arthritis and put forward some prospects for the future research.

Background: Culture is a key step for detecting periprosthetic joint infection (PJI) before surgery. However, using saline solution lavage and reaspiration in patients with insufficient synovial fluid remains controversial. The objective of this study was to evaluate this technique. Methods: This study included 286 aspirations performed by 1 surgeon in patients after total joint arthroplasty during the period of April 2015 to August 2018. If >1.0 mL of synovial fluid was obtained, then we directly used the fluid for culture. For cases in which ≤1.0 mL of synovial fluid was aspirated, 10 mL of saline solution was injected and the joint was reaspirated for culture. The samples were injected into 2 blood culture bottles for anaerobic bacterial culture and aerobic bacterial and fungal culture, and were inoculated for 14 days in a BACT/ALERT 3D blood culture system unless microorganisms were detected. A PJI diagnosis was determined on the basis of the modified Musculoskeletal Infection Society criteria. Results: Saline solution lavage and reaspiration were used in 82 cases (47 PJI cases and 35 non-PJI cases), while direct aspiration was used in 204 cases (99 PJI cases and 105 non-PJI cases). The overall rate for the use of saline solution lavage was 28.7% (82 of 286). Among knee cases, the saline solution lavage rate was 15.0% (21 of 140), and among hip cases, the rate was 41.8% (61 of 146). The overall sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of culture were 0.795 (95% confidence interval [CI], 0.720 to 0.857), 0.957 (95% CI, 0.909 to 0.984), 0.951 (95% CI, 0.896 to 0.982), and 0.817 (95% CI, 0.749 to 0.873); and for “dry tap” cases, they were 0.851 (95% CI, 0.717 to 0.938), 0.857 (95% CI, 0.697 to 0.952), 0.889 (95% CI, 0.760 to 0.963), and 0.811 (95% CI, 0.648 to 0.920), respectively. Conclusions: Saline solution lavage and reaspiration for culture in patients with insufficient synovial fluid before surgery may be a sound practice. Level of Evidence: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The number of orthopedic implants for bone fixation and joint arthroplasty has been steadily increasing over the past few years. However, implant-associated infection (IAI), a major complication in orthopedic surgery, impacts the quality of life and causes a substantial economic burden on patients and societies. While research and study on IAI have received increasing attention in recent years, the failure rate of IAI has still not decreased significantly. This is related to microbial biofilms and their inherent antibiotic resistance, as well as the various mechanisms by which bacteria evade host immunity, resulting in difficulties in diagnosing and treating IAIs. Hence, a better understanding of the complex interactions between biofilms, implants, and host immunity is necessary to develop new strategies for preventing and controlling these infections. This review first discusses the challenges in diagnosing and treating IAI, followed by an extensive review of the direct effects of orthopedic implants, host immune function, pathogenic bacteria, and biofilms. Finally, several promising preventive or therapeutic alternatives are presented, with the hope of mitigating or eliminating the threat of antibiotic resistance and refractory biofilms in IAI.

Background: Antibiotic resistance is one of the main global threats to human health, and just the development of new antimicrobial medications is not enough to solve the crisis. Phage therapy (PT), a safe and effective treatment method, has reignited the interest of researchers due to its efficacy in the clinical treatment of drug-resistant bacterial infections. There is, however, no bibliometric analysis of the overall trends on this topic. Therefore, this study aims to provide an overview of the current state of development and research in this area.Methods: We extracted all relevant publications from the Web of Science Core Collection (WoSCC) database between 2001 and 2021. We performed bibliometric analysis and visualization using CiteSpace, VOS viewer, and R software. Annual trends of publications, countries/regions distributions, institutions, funding agencies, co-cited journals, author contributions, core journals, references, and keywords were analyzed.Results: A total of 6,538 papers were enrolled in this study, including 5,364 articles and 1,174 reviews. Publications have increased drastically from 61 in 2001 to 937 in 2021, with 3,659 articles published in the last 5 years. North America, Western Europe, and East Asia were significant contributor regions. The United States, China, and the United Kingdom were the most productive countries. The Polish Academy of Sciences was the most contributive institution. Frontiers in Microbiology and Applied and Environmental Microbiology were the most productive and co-cited journals. A. Gorski and R. Lavigne published most articles in this field, while V. A. Fischetti was the author with the most cited. Regarding keywords, research focuses include phage biology, phage against clinically important pathogens, phage lysis proteins, phage therapy, biofilm-related research, and recent clinical applications.Conclusion: Phage therapy is a potential strategy for combating antibiotic resistance, and it will provide us with an alternative therapeutic option for bacterial infection. According to global trends, the scientific output of PT in bacterial infections is increasing, with developed countries such as the United States leading the way in this area. Although the safety and efficacy of PT have been proven, more clinical trials on the phages against infectious diseases caused by various pathogens are still needed.