Challenges in Residual Bearing Removal: A Rare Case of Mobile Bearing Fracture in Unicompartmental Knee Arthroplasty with Literature Review.

BACKGROUND: Mobile bearing fracture is a rare long-term complication of unicompartmental knee arthroplasty (UKA), and relevant reports are sparse. Hence, its treatment options need further exploration. CASE PRESENTATION: This study presents the case of fracture of a polyethylene insert that occurred 12 years after mobile bearing medial UKA in a 75-year-old overweight woman who then underwent surgical intervention at our institution. However, we encountered significant challenges in removing the fragments from the broken bearing, resulting in retention of the remaining one-third of the fragment. We solved this problem by replacing the fractured insert with thicker mobile bearing. During the 1-month postoperative follow-up, the patient achieved good range of motion and excellent satisfaction, with no reported complications and a Knee Society Score of 90. Additionally, we reviewed the literature on the treatment for mobile bearing fractures after UKA. CONCLUSIONS: Bearing fracture is a rare cause of failure of mobile bearing UKA. This case highlights the challenges of UKA fracture bearing retrieval and underscores that mobile bearing replacement can be an effective intervention. The case we report shows that when removal of a residual meniscal bearing in a posterior dislocation is difficult to achieve, compromise may be an appropriate option because it does not cause additional complaints to the patient. This case emphasizes the importance of the surgeon having a thorough preoperative understanding of the location and potential pitfalls of fracture fragments in such situations.

Radiographic evaluation of robot-assisted versus manual total hip arthroplasty: a multicenter randomized controlled trial.

BACKGROUND: The effectiveness of robot-assisted surgery remains contentious due to the lack of high-quality randomized controlled trials (RCTs) to elevate the level of evidence. We aimed to evaluate the postoperative radiographic outcomes of robot-assisted (RAS-THA) versus manual (M-THA) total hip arthroplasty. METHODS: This multicenter RCT was performed from March 1, 2021 to December 1, 2021. Patients were randomly assigned to routine M-THA or to RAS-THA that used the TRex-RS orthopedic joint surgical navigation system. The primary outcome was to compare the acetabular component orientation, femoral stem alignment, femoral canal fill ratio, and leg length discrepancy between RAS-THA and M-THA using postoperative radiography. Subgroup analyses of the two groups stratified by surgical approach, gender, and BMI were also conducted. RESULTS: Seventy-three participants were randomly allocated to the RAS-THA group, while seventy-two participants were assigned to the M-THA group. Compared to the M-THA group, the RAS-THA group exhibited less variability in the preoperative planning of the vertical center of rotation (VCOR; P < 0.001), demonstrated a significant advantage in femoral stem alignment (P = 0.004), and showed pronounced decreases in inequality and in the variability in leg length discrepancy (P < 0.001). There was no significant difference in the Lewinnek safe-zone ratio (P = 0.081) and the femoral canal fill ratio (P > 0.05) between the two groups. Further subgroup analysis also showed that the RAS-THA group had fewer horizontal center of rotation (HCOR) and leg length differences when stratified by surgical approach, gender, and overweight status. CONCLUSION: This RCT found that, regardless of the surgical approach, gender, or body mass index, RAS-THA can effectively improve the postoperative VCOR and significantly reduce the variability of leg length difference. RAS-THA should be considered an effective method to enhance surgical precision by achieving less variability in challenging patients with leg length discrepancies. TRIAL REGISTRATION: ChiCTR2100044124.

Total Hip Arthroplasty Combined with Proximal Femoral Reconstruction Effectively Treats Severe Hip Deformities: A Novel Osteotomy Technique.

OBJECTIVE: Total hip arthroplasty (THA) combined with proximal femoral reconstruction is a novel osteotomy technique developed to address severe hip deformities. There is a paucity of robust clinical and radiological evidence regarding the outcomes of this novel osteotomy technique. This study aimed to evaluate the clinical and radiological outcomes of THA combined with proximal femoral reconstruction during the early follow-up. METHODS: This is a retrospective case series of 63 hips who underwent THA combined with proximal femoral reconstruction at a single institution between January 2020 and July 2023. The mean age of patients was 39.6 ± 12.6 years. The mean follow-up was 25.6 ± 3.8 months. Surgical characteristics and perioperative variables were evaluated to assess the efficacy of this technique. Harris hip score (HHS) was utilized to evaluate hip function. Leg length discrepancy (LLD) was evaluated in X-ray. The incidence of major adverse events including deep vein thrombosis (DVT), osteolysis, nonunion of the osteotomy, intraoperative femoral fracture, and infection was also evaluated. Paired-samples t-test was used to compare preoperative and postoperative HHS and LLD. RESULTS: The mean operative time was 125.1 min. The mean size of the acetabular components used was 45.2 mm, and the stem size was 7.5. The primary friction interface was ceramic-on-ceramic, accounting for 92.1% of cases. The average length of hospital stay was 8.5 days. The mean cost of treatment was 46,296.0 Yuan. There was a significant improvement in postoperative HHS (p < 0.001) and LLD (p < 0.001) compared to preoperative values. The incidence of deep venous thrombosis was 4.8%; osteolysis rates for the cup and stem were 4.8% and 6.4%, respectively. The non-union and dislocation rates were 1.6% and 3.2%, respectively. There was no incidence of postoperative infection. CONCLUSION: The novel osteotomy surgical procedure yields reliable and impressive clinical and radiological outcomes, with minimal complications. We advocate for its use in complex primary THA cases involving severe proximal femoral deformities.

Outcomes of a Double-Cup Construct to Treat Paprosky 3A and 3B Acetabular Defects at a Mean of 39 Months.

BACKGROUND: Modular reconstruction systems based on porous tantalum (PT) prosthetic components have been increasingly used for the treatment of complex acetabular bone defects in revision total hip arthroplasty. We report a novel technique that applies a revision cup as a "super-augment" to form a "double-cup" construct for Paprosky type III defects. METHODS: A retrospective review was conducted on revision total hip arthroplasty cases, comparing those treated with double-cup constructs (DC group, n = 48) to those treated with PT shells and augments (PT group, n = 48). All procedures were performed at the same institute between 2017 and 2022. Clinical outcome evaluation utilized the Harris Hip Score, Oxford Hip Score, and the 36-Item Short Form Survey. Preoperative and postoperative radiographic assessments measured hip center of rotation (COR) position and leg length discrepancy. Additionally, postoperative complications and implant survivorship were monitored during the follow-up period. RESULTS: The clinical outcomes improved substantially in both groups, which showed no significant difference in the Harris Hip Score (P = .786), the Oxford Hip Score (P = .570), and the 36-Item Short Form Survey (P = .691). Compared to the PT group, the reconstruction COR was significantly closer to the anatomic COR (vertical distance: 2.630 versus 7.355 mm, P = .0034; horizontal distance: 1.881 versus -6.413 mm, P < .0001) in Paprosky 3B type defects. Additionally, postoperative leg length discrepancy was less in the DC group (-8.252 versus -1.821 mm, P = .0008). Dislocation was the main complication in the DC group, and only 1 patient received re-revision due to repeated dislocation. The cumulative survival rate of the DC group (100%; 95% confidence interval 100) was better than the PT group (83.4%; 95% confidence interval 70.5 to 98.6) when re-revisions for aseptic loosening were the endpoint (P = .046). CONCLUSIONS: The DC is a reliable revision technique for the reconstruction of Paprosky type III bone defects. Although dislocation remains challenging, the biomechanically superior restoration achieved by this technique lowers the risk of aseptic loosening.

Mussel-Derived and Bioclickable Peptide Mimic for Enhanced Interfacial Osseointegration via Synergistic Immunomodulation and Vascularized Bone Regeneration.

Inadequate osseointegration at the interface is a key factor in orthopedic implant failure. Mechanistically, traditional orthopedic implant interfaces fail to precisely match natural bone regeneration processes in vivo. In this study, a novel biomimetic coating on titanium substrates (DPA-Co/GFO) through a mussel adhesion-mediated ion coordination and molecular clicking strategy is engineered. In vivo and in vitro results confirm that the coating exhibits excellent biocompatibility and effectively promotes angiogenesis and osteogenesis. Crucially, the biomimetic coating targets the integrin α2ß1 receptor to promote M2 macrophage polarization and achieves a synergistic effect between immunomodulation and vascularized bone regeneration, thereby maximizing osseointegration at the interface. Mechanical push-out tests reveal that the pull-out strength in the DPA-Co/GFO group is markedly greater than that in the control group (79.04 ± 3.20 N vs 31.47 ± 1.87 N, P < 0.01) and even surpasses that in the sham group (79.04 ± 3.20 N vs 63.09 ± 8.52 N, P < 0.01). In summary, the novel biomimetic coating developed in this study precisely matches the natural process of bone regeneration in vivo, enhancing interface-related osseointegration and showing considerable potential for clinical translation and applications.

Balancing Bioresponsive Biofilm Eradication and Guided Tissue Repair via Pro-Efferocytosis and Bidirectional Pyroptosis Regulation during Implant Surgery.

There is an increasingly growing demand to balance tissue repair guidance and opportunistic infection (OI) inhibition in clinical implant surgery. Herein, we developed a nanoadjuvant for all-stage tissue repair guidance and biofilm-responsive OI eradication via in situ incorporating Cobaltiprotoporphyrin (CoPP) into Prussian blue (PB) to prepare PB-CoPP nanozymes (PCZs). Released CoPP possesses a pro-efferocytosis effect for eliminating apoptotic and progressing necrotic cells in tissue trauma, thus preventing secondary inflammation. Once OIs occur, PCZs with switchable nanocatalytic capacity can achieve bidirectional pyroptosis regulation. Once reaching the acidic biofilm microenvironment, PCZs possess peroxidase (POD)-like activity that can generate reactive oxygen species (ROS) to eradicate bacterial biofilms, especially when synergized with the photothermal effect. Furthermore, generated ROS can promote macrophage pyroptosis to secrete inflammatory cytokines and antimicrobial proteins for biofilm eradication in vivo. After eradicating the biofilm, PCZs possess catalase (CAT)-like activity in a neutral environment, which can scavenge ROS and inhibit macrophage pyroptosis, thereby improving the inflammatory microenvironment. Briefly, PCZs as nanoadjuvants feature the capability of all-stage tissue repair guidance and biofilm-responsive OI inhibition that can be routinely performed in all implant surgeries, providing a wide range of application prospects and commercial translational value.

Quantifying the dose-response relationship between exercise and health-related quality of life in patients undergoing haemodialysis: A meta-analysis.

Objective: This meta-analysis aims to explore the dose-response relationship of aerobic exercise or aerobic combined resistance exercise on cardiopulmonary function in maintenance hemodialysis（MHD）, with the goal of aiding in the formulation of precise exercise prescriptions. Methods: A literature search up to August 18, 2023, was conducted in databases including Web of Science, among others, focusing on the effects of exercise interventions on cardiopulmonary function in hemodialysis patients.Two researchers independently conducted literature screening, data extraction, and an assessment of study methodology quality. A dose-response meta-analysis was carried out using a one-stage cubic spline mixed-effects model, followed by stratified analyses based on intervention period, intervention method, and exercise environment. Results: A nonlinear dose-response relationship was observed between exercise and 6-minute walk test (6WMT) as well as peak oxygen uptake (VO2Peak) in hemodialysis patients. The optimal exercise dose for the 6WMT across the full exposure range was 922 METs-min/week, with VO2Peak increasing with the dose. The effects were influenced by the type of exercise, intervention period, and exercise environment. An exercise dose of 500 METs-min/week and 619 METs-min/week was found sufficient to achieve the minimal clinically important differences (MCID) for 6WMT and VO2Peak, respectively. Conclusion: There is a significant association between the dose of exercise and its effects. With appropriate adjustment of variables, even low-dose exercise can lead to clinically significant improvements in cardiopulmonary function.

Exosomes based strategies for cardiovascular diseases: Opportunities and challenges.

Exosomes, as nanoscale extracellular vesicles (EVs), are secreted by all types of cells to facilitate intercellular communication in living organisms. After being taken up by neighboring or distant cells, exosomes can alter the expression levels of target genes in recipient cells and thereby affect their pathophysiological outcomes depending on payloads encapsulated therein. The functions and mechanisms of exosomes in cardiovascular diseases have attracted much attention in recent years and are thought to have cardioprotective and regenerative potential. This review summarizes the biogenesis and molecular contents of exosomes and details the roles played by exosomes released from various cells in the progression and recovery of cardiovascular disease. The review also discusses the current status of traditional exosomes in cardiovascular tissue engineering and regenerative medicine, pointing out several limitations in their application. It emphasizes that some of the existing emerging industrial or bioengineering technologies are promising to compensate for these shortcomings, and the combined application of exosomes and biomaterials provides an opportunity for mutual enhancement of their performance. The integration of exosome-based cell-free diagnostic and therapeutic options will contribute to the further development of cardiovascular regenerative medicine.

The obesity challenge in joint replacement: a multifaceted analysis of self-reported health status and exercise capacity using NHANES data: a population-based study.

BACKGROUND: Joint replacement is successful for end-stage oeteoarthritis, with obesity linked to elevated risk. But the impact of obesity on self-reported health and exercise capacity among joint replacement patients remains complex and requires investigation. METHODS: This study utilizes data from the National Health and Nutrition Examination Survey (NHANES) to examine the relationship between obesity severity, demographic factors, medical comorbidities, and self-reported health status. The relationship between general health status and BMI was analyzed using multivariable regression, and further illustrated using a restricted cubic spline. Additionally, a bibliometric analysis and systematic review was done to frame the research within the broader context of existing knowledge and demographic specifics. RESULTS: Analysis of NHANES data involving 327 joint replacement patients yielded intriguing insights. The difference in self-reported health between BMI groups did not achieve conventional statistical significance ( P =0.06), and multivariable analysis showed that even severely obese patients did not exhibit significantly elevated risk of poor/fair self-reported health compared to normal weight subjects. Among severely obese individuals (BMI>40), 40.63% still rated their health positively. However, stratified analyses indicated that obesity correlated with negative health reports across sex, age, and education strata. Notably, physical functioning emerged as a robust predictor of self-reported health, with those reporting no walking difficulties having significantly lower odds of poor/fair health (Odds ratio=0.37, P =0.01). CONCLUSION: The study highlights the need for healthcare providers to consider individual physical abilities and comorbidities alongside obesity severity when discussing treatment options with joint replacement patients. It supports tailored interventions and informed shared decision-making. Future research could explore effective weight management strategies for obese individuals undergoing joint replacement.

Honeycomb-inspired ZIF-sealed interface enhances osseointegration via anti-infection and osteoimmunomodulation.

Implant-associated infections (IAIs) pose a significant threat to orthopedic surgeries. Bacteria colonizing the surface of implants disrupt bone formation-related cells and interfere with the osteoimmune system, resulting in an impaired immune microenvironment and osteogenesis disorders. Inspired by nature, a zeolitic imidazolate framework (ZIF)-sealed smart drug delivery system on Ti substrates (ZSTG) was developed for the "natural-artificial dual-enzyme intervention (NADEI)" strategy to address these challenges. The subtle sealing design of ZIF-8 on the TiO2 nanotubes ensured glucose oxidase (GOx) activity and prevented its premature leakage. In the acidic infection microenvironment, the degradation of ZIF-8 triggered the rapid release of GOx, which converted glucose into H2O2 for disinfection. The Zn2+ released from degraded ZIF-8, as a DNase mimic, can hydrolyze extracellular DNA, which further enhances H2O2-induced disinfection and prevents biofilm formation. Importantly, Zn2+-mediated M2 macrophage polarization significantly improved the impaired osteoimmune microenvironment, accelerating bone repair. Transcriptomics revealed that ZSTG effectively suppressed the inflammatory cascade induced by lipopolysaccharide while promoting cell proliferation, homeostasis maintenance, and bone repair. In vitro and in vivo results confirmed the superior anti-infective, osteoimmunomodulatory, and osteointegrative capacities of the ZSTG-mediated NADEI strategy. Overall, this smart bionic platform has significant potential for future clinical applications to treat IAIs.

Exploring the Epidemiology of Injuries in Athletes of the Olympic Winter Games: A Systematic Review and Meta-Analysis.

This study sought to provide a comprehensive assessment of the incidence of sports injuries among athletes participating in the Olympic Winter Games and to investigate contributing factors. We gathered injury data from athletes participating in the recent four Olympic Winter Games, incorporating details on the sports event, sex, injury location, and type. Through a meta-analysis, we calculated the injury incidence rates for each sport and examined the influence of sex and the type of sport on these incidence rates. Out of 11,197 registered athletes, we documented 1,304 sports injuries. The sports events with the highest injury rates were freestyle skiing, snowboarding, alpine skiing, bobsleigh, and ice hockey, with the most frequent injury locations being the knees, thoracic/lumbar/back regions, and the wrist/hand/fingers. Contusions, hematomas, and bruises were the most prevalent injuries, followed by strains (including muscle rupture, tearing, or tendon rupture) and sprains (covering dislocations, subluxations, and ligament ruptures). In the Olympic Winter Games, events such as freestyle skiing, snowboarding, alpine skiing, bobsleigh, and ice hockey pose a particularly high risk. Predominant injury sites include the knee, spine/back, and wrist and hand, with injuries ranging from contusions and hematomas to strains and sprains. For effective injury prevention, it is crucial to emphasize proper medical resource allocation, specialized training for medical personnel, and meticulous venue maintenance.

The landscape of patellofemoral arthroplasty research: a bibliometric analysis.

PURPOSE: Patellofemoral arthroplasty (PFA) was shown to be a potentially effective surgical technique for isolated patellofemoral osteoarthritis but varying reports on PFA-related implant failure and complications have rendered the procedure controversial. This study aimed to identify impactful publications, research interests/efforts, and collaborative networks in the field of PFA research. METHODS: The study used the Web of Science Core Collection (WOSCC) database, Medline, Springer, BIOSIS Citation Index, and PubMed to retrieve relevant publications on PFA research published between 1950-2022. Statistical tests in R software were used for analysis while VOSviewer, Bibliometrix, and CiteSpace were employed for data visualization. RESULTS: Two hundred forty-one articles were analyzed with the number of published papers increasing over time. Knee was the most frequent journal and Clinical Orthopaedics and Related Research was the most cited journal. Clinical outcomes, such as prosthesis survival, revision, and complications, were researched most frequently as demonstrated by keyword analysis. The United States was the top contributor to cooperative networks, followed by the United Kingdom while Technical University Munich formed close ties among authors. CONCLUSION: Publications on PFA research have witnessed a notable surge. They primarily came from a limited number of centers and were characterized by low-level evidence. The majority of studies primarily focused on the clinical outcomes of PFA, while revision of PFA and patient satisfaction have emerged as new research areas.

Physically cross-linked organo-hydrogels for friction interfaces in joint replacements: design, evaluation and potential clinical applications.

This paper investigates physically crosslinked organo-hydrogels for total hip replacement surgery. Current materials in artificial joints have limitations in mechanical performance and biocompatibility. To overcome these issues, a new approach based on hydrogen bonds between polyvinyl alcohol, poly(2-hydroxyethyl methacrylate), and glycerin is proposed to develop bioactive organo-hydrogels with improved mechanical properties and biocompatibility. This study analyzes local pathological characteristics, systemic toxicity, and mechanical properties of the gels. The results show that the gels possess excellent biocompatibility and mechanical strength, suggesting their potential as an alternative material for total hip replacement surgery. These findings contribute to improving patient outcomes in joint replacement procedures.

Tracing the evolution of robotic-assisted total knee arthroplasty: a bibliometric analysis of the top 100 highly cited articles.

Robotic-assisted surgical systems hold promise in enhancing total knee arthroplasty (TKA) outcomes and patients' quality of life. This study aims to comprehensively analyze the literature on robot-assisted total knee arthroplasty (r-TKA), providing insights into its current development, clinical application, and research trends. A systematic search was conducted in the Web of Science Core Collection (WOSCC) to identify relevant articles. Data were collected from the top 100 highly cited articles. Article evidence levels were assessed following established guidelines. Statistical analyses and visualizations were performed to reveal publication trends, citations, research hotspots, and collaborative networks. The analysis covered 100 highly cited articles meeting the research criteria, with a focus on the last five years. The United States emerged as a major contributor, with most publications and citations in the Journal of Knee Surgery and Knee Surgery Sports Traumatology Arthroscopy. Research priorities revolved around clinical outcomes, accuracy, and alignment of r-TKA. Notably, higher evidence levels correlated with more citations, indicating greater attention. Interest in and research on r-TKA is steadily increasing, with a few countries at the forefront of these endeavors. While numerous studies have already reported short- to medium-term follow-up results, it is crucial to conduct longer-term investigations to gain a more comprehensive understanding of the clinical benefits that r-TKA offers compared to conventional techniques. Through ongoing research and a greater embrace of robotic technology, we can continue to improve the quality of life for patients undergoing knee arthroplasty.

Metformin reverses impaired osteogenesis due to hyperglycemia-induced neutrophil extracellular traps formation.

Diabetic patients suffer from delayed fracture healing and impaired osteogenic function, but the underlying pathophysiological mechanisms are not fully understood. Neutrophil extracellular traps (NETs) formed by neutrophils in high glucose microenvironments affect the healing of wounds and other tissues. Some evidence supports that NETs may inhibit osteogenic processes in the microenvironment through sustained inflammatory activation. In this study, we observed that high glucose-induced NETs led to sustained inflammatory activation of macrophages. Pro-inflammatory NETs inhibited the osteogenic function of osteoblasts in vitro. A bone defect healing model based on diabetic rat animal models confirmed that bone healing was impaired in a high glucose environment, but this process could be reversed by DNase I, a NETs clearance agent. More importantly, the classic hypoglycemic drug metformin had a similar antagonistic effect as DNase I and could reverse the inhibitory effect of NETs on osteogenesis in a high-glucose environment. In summary, we found that NETs formation induced by high glucose microenvironment is a potential cause of osteogenic dysfunction in diabetic patients, and metformin can reverse this osteogenic disadvantage.

Inflammation-Responsive Hydrogel Spray for Synergistic Prevention of Traumatic Heterotopic Ossification via Dual-Homeostatic Modulation Strategy.

Traumatic heterotopic ossification (THO) represents one of the most prominent contributors to post-traumatic joint dysfunction, which currently lacks an effective and definitive preventative approach. Inflammatory activation due to immune dyshomeostasis during the early stages of trauma is believed to be critical in initiating the THO disease process. This study proposes a dual-homeostatic modulation (DHM) strategy to synergistically prevent THO without compromising normal trauma repair by maintaining immune homeostasis and inducing stem cell homeostasis. A methacrylate-hyaluronic acid-based hydrogel spray device encapsulating a curcumin-loaded zeolitic imidazolate framework-8@ceric oxide (ZIF-8@CeO2, CZC) nanoparticles (CZCH) is designed. Photo-crosslinked CZCH is used to form hydrogel films fleetly in periosteal soft tissues to achieve sustained curcumin and CeO2 nanoparticles release in response to acidity and reactive oxygen species (ROS) in the inflammatory microenvironment. In vitro experiments and RNA-seq results demonstrated that CZCH achieved dual-homeostatic regulation of inflammatory macrophages and stem cells through immune repolarization and enhanced efferocytosis, maintaining immune cell homeostasis and normal differentiation. These findings of the DHM strategy are also validated by establishing THO mice and rat models. In conclusion, the CZCH hydrogel spray developed based on the DHM strategy enables synergistic THO prevention, providing a reference for a standard procedure of clinical operations.

Biofilm Microenvironment-Responsive Self-Assembly Nanoreactors for All-Stage Biofilm Associated Infection through Bacterial Cuproptosis-like Death and Macrophage Re-Rousing.

Bacterial biofilm-associated infections (BAIs) are the leading cause of prosthetic implant failure. The dense biofilm structure prevents antibiotic penetration, while the highly acidic and H2 O2 -rich biofilm microenvironment (BME) dampens the immunological response of antimicrobial macrophages. Conventional treatments that fail to consistently suppress escaping planktonic bacteria from biofilm result in refractory recolonization, allowing BAIs to persist. Herein, a BME-responsive copper-doped polyoxometalate clusters (Cu-POM) combination with mild photothermal therapy (PTT) and macrophage immune re-rousing for BAI eradication at all stages is proposed. The self-assembly of Cu-POM in BME converts endogenous H2 O2 to toxic ·OH through chemodynamic therapy (CDT) and generates a mild PTT effect to induce bacterial metabolic exuberance, resulting in loosening the membrane structure of the bacteria, enhancing copper transporter activity and increasing intracellular Cu-POM flux. Metabolomics reveals that intracellular Cu-POM overload restricts the TCA cycle and peroxide accumulation, promoting bacterial cuproptosis-like death. CDT re-rousing macrophages scavenge planktonic bacteria escaping biofilm disintegration through enhanced chemotaxis and phagocytosis. Overall, BME-responsive Cu-POM promotes bacterial cuproptosis-like death via metabolic interference, while also re-rousing macrophage immune response for further planktonic bacteria elimination, resulting in all-stage BAI clearance and providing a new reference for future clinical application.

Are patients with preoperative synovitis suitable for unicompartmental knee arthroplasty? Magnetic resonance imaging evidence from a retrospective cohort study.

BACKGROUND: The use of unicompartmental knee arthroplasty (UKA) in patients with preoperative synovitis is controversial. This study aimed to investigate the association between synovitis detected by magnetic resonance imaging (MRI) and prognosis after UKA. METHODS: Synovitis was graded using the MRI Osteoarthritis Knee Score criteria based on preoperative MRI findings of 132 UKAs performed between June 2020 and August 2021. The Knee Society Knee Score (KS-KS) and the Knee Society Function Score were collected preoperatively and 1 year postoperatively. The relationship between synovitis and the changes in the Knee Society score was analyzed using logistic regression. RESULTS: Univariate logistic regression showed that patients with higher preoperative synovitis scores (odds ratio (OR) = 1.925, 95% confidence interval (CI): 1.482-2.500, P < 0.001) had higher KS-KS changes. After adjusting for confounding variables, synovitis was proven to be an independent factor for KS-KS improvement after UKA in multivariate logistic regression (OR = 1.814, 95% CI: 1.354-2.430, P < 0.001). Before UKA, patients with synovitis had lower pain scores (PS) than patients without synovitis (95% CI: -17.159 - -11.160, t = -9.347, P < 0.001). There was no difference in PS between the two groups after UKA (95% CI: -6.559 - 0.345, t = -1.782, P = 0.077). CONCLUSIONS: Patients with synovitis can achieve good improvement of pain symptoms, and the efficacy is not inferior to that of non-synovitis patients after UKA.

Biofilm Homeostasis Interference Therapy via 1 O2 -Sensitized Hyperthermia and Immune Microenvironment Re-Rousing for Biofilm-Associated Infections Elimination.

The recurrence of biofilm-associated infections (BAIs) remains high after implant-associated surgery. Biofilms on the implant surface reportedly shelter bacteria from antibiotics and evade innate immune defenses. Moreover, little is currently known about eliminating residual bacteria that can induce biofilm reinfection. Herein, novel "interference-regulation strategy" based on bovine serum albumin-iridium oxide nanoparticles (BIONPs) as biofilm homeostasis interrupter and immunomodulator via singlet oxygen (1 O2 )-sensitized mild hyperthermia for combating BAIs is reported. The catalase-like BIONPs convert abundant H2 O2 inside the biofilm-microenvironment (BME) to sufficient oxygen gas (O2 ), which can efficiently enhance the generation of 1 O2 under near-infrared irradiation. The 1 O2 -induced biofilm homeostasis disturbance (e.g., sigB, groEL, agr-A, icaD, eDNA) can disrupt the sophisticated defense system of biofilm, further enhancing the sensitivity of biofilms to mild hyperthermia. Moreover, the mild hyperthermia-induced bacterial membrane disintegration results in protein leakage and 1 O2 penetration to kill bacteria inside the biofilm. Subsequently, BIONPs-induced immunosuppressive microenvironment re-rousing successfully re-polarizes macrophages to pro-inflammatory M1 phenotype in vivo to devour residual biofilm and prevent biofilm reconstruction. Collectively, this 1 O2 -sensitized mild hyperthermia can yield great refractory BAIs treatment via biofilm homeostasis interference, mild-hyperthermia, and immunotherapy, providing a novel and effective anti-biofilm strategy.