Analysis of the incidence and risk factors of blood transfusion in total knee revision: a retrospective nationwide inpatient sample database study.

OBJECTIVE: This study sought to determine the incidence and risk factors of blood transfusion among patients undergoing total knee revision (TKR) using a nationwide database. METHODS: A retrospective data analysis was conducted based on the Nationwide Inpatient Sample (NIS), enrolling patients who underwent TKR from 2010 to 2019 with complete information. The patients were divided into two groups based on whether they received blood transfusion or not. The demographic characteristics (race, sex, and age), length of stay (LOS), total charge of hospitalization, hospital characteristics (admission type, insurance type, bed size, teaching status, location, and region of hospital), hospital mortality, comorbidities, and perioperative complications were analyzed. Finally, we conducted univariate and multivariate logistic regression to identify factors that were associated with TKR patients to require blood transfusion. RESULTS: The NIS database included 115,072 patients who underwent TKR. Among them, 14,899 patients received blood transfusion, and the incidence of blood transfusion was 13.0%. There was a dramatic decrease in the incidence over the years from 2010 to 2019, dropping from 20.4 to 6.5%. TKR patients requiring transfusions had experienced longer LOS, incurred higher total medical expenses, utilized Medicare more frequently, and had increased in-hospital mortality rates (all P < 0.001). Independent predictors for blood transfusion included advanced age, female gender, iron-deficiency anemia, rheumatoid disease, chronic blood loss anemia, congestive heart failure, coagulopathy, uncomplicated diabetes, lymphoma, fluid and electrolyte disorders, metastatic carcinoma, other neurological diseases, paralysis, peripheral vascular disorders, pulmonary circulation disorders, renal failure, valvular disease, and weight loss. In addition, risk factors for transfusion in TKR surgery included sepsis, acute myocardial infarction, deep vein thrombosis, pulmonary embolism, gastrointestinal bleeding, heart failure, renal insufficiency, pneumonia, wound infection, lower limb nerve injury, hemorrhage/seroma/hematoma, wound rupture/non healing, urinary tract infection, acute renal failure, and postoperative delirium. CONCLUSIONS: Our findings highlight the importance of recognizing the risk factors of blood transfusion in TKR to reduce the occurrence of adverse events.

Advanced glycation end products promote meniscal calcification by activating the mTOR-ATF4 positive feedback loop.

The meniscus is vital for maintaining knee homeostasis and function. Meniscal calcification is one of the earliest radiological indicators of knee osteoarthritis (KOA), and meniscal calcification is associated with alterations in biomechanical properties. Meniscal calcification originates from a biochemical process similar to vascular calcification. Advanced glycation end products (AGEs) and their receptors (RAGEs) reportedly play critical roles in vascular calcification. Herein, we investigated whether targeting AGE-RAGE is a potential treatment for meniscal calcification. In our study, we demonstrated that AGE-RAGE promotes the osteogenesis of meniscal cells and exacerbates meniscal calcification. Mechanistically, AGE-RAGE activates mTOR and simultaneously promotes ATF4 accumulation, thereby facilitating the ATF4-mTOR positive feedback loop that enhances the osteogenic capacity of meniscal cells. In this regard, mTOR inhibits ATF4 degradation by reducing its ubiquitination, while ATF4 activates mTOR by increasing arginine uptake. Our findings substantiate the unique role of AGE-RAGE in the meniscus and reveal the role of the ATF4-mTOR positive feedback loop during the osteogenesis of meniscal cells; these results provide potential therapeutic targets for KOA.

Protective effects of ectoine on articular chondrocytes and cartilage in rats for treating osteoarthritis.

Osteoarthritis (OA) is a chronic degenerative disease that primarily includes articular cartilage destruction and inflammatory reactions, and effective treatments for this disease are still lacking. The present study aimed to explore the protective effects of ectoine, a compatible solute found in nature, on chondrocytes in rats and its possible application in OA treatment. In the in vitro studies, the morphology of the chondrocytes after trypsin digestion for 2 min and the viability of the chondrocytes at 50°C were observed after ectoine treatment. The reactive oxygen species (ROS) levels in chondrocytes pretreated with ectoine and post-stimulated with H2O2 were detected using an ROS assay. Chondrocytes were pretreated with ectoine before IL-1ß stimulation. RT‒qPCR was used to measure the mRNA levels of cyclooxygenase-2 (COX-2), metallomatrix proteinase-3, -9 (MMP-3, -9), and collagen type II alpha 1 (Col2A1). In addition, immunofluorescence was used to assess the expression of type II collagen. The in vivo effect of ectoine was evaluated in a rat OA model induced by the modified Hulth method. The findings revealed that ectoine significantly increased the trypsin tolerance of chondrocytes, maintained the viability of the chondrocytes at 50°C, and improved their resistance to oxidation. Compared with IL-1ß treatment alone, ectoine pretreatment significantly reduced COX-2, MMP-3, and MMP-9 expression and maintained type II collagen synthesis in chondrocytes. In vivo, the cartilage of ectoine-treated rats exhibited less degeneration and lower Osteoarthritis Research Society International (OARSI) scores. The results of this study suggest that ectoine exerts protective effects on chondrocytes and cartilage and can, therefore, be used as a potential therapeutic agent in the treatment of OA.

Comparison of clinical, imaging and second-look arthroscopic outcomes between varus knee patients with and without preoperative tibial varus deformity after medial opening-wedge high tibial osteotomy.

PURPOSE: This study aimed to compare the regeneration status of articular cartilage, clinical, and radiologic outcomes between varus knee patients with and without preoperative tibial varus deformity (PTVD) after medial opening-wedge high tibial osteotomy (OWHTO) METHODS: Varus knee patients who had undergone OWHTO were divided into two groups according to preoperative medial proximal tibial angle (MPTA): a great varus (GV) group (MPTA <85°) and a mild varus (MV) group (85°≤preoperative MPTA <87°). The hip-knee-ankle (HKA) angle, weight-bearing line ratio (WBL%), MPTA, joint line convergence angle and joint line obliquity were measured. Second-look arthroscopy was undertaken 24 months after HTO. The Knee Society (KS) function score and knee score, and Lysholm score were used to evaluate the functional outcomes. All parameters were evaluated preoperatively and 24 months after HTO. RESULTS: The GV group had greater varus than the MV group in HKA and WBL% before surgery, but greater valgus after surgery. The arthroscopic probe before HTO revealed the advanced chondral damage in the GV group and lighter chondral damage in the MV group. The regeneration of medial femoral condyle was considerably more frequent in the GV group (72.5%, 45/62) than in the MV group (50.0%, 27/54) (P = 0.030). No significant differences were observed in all functional outcomes preoperatively and 24 months after HTO. CONCLUSION: The extent of cartilage regeneration in patients without PTVD was inferior to that in those with PTVD, but the functional outcomes were comparable. OWHTO may be a treatment option in a selected subset of varus knee patients without PTVD.

circIFNGR2 regulating ankylosing spondylitis-associated inflammation through macrophage polarization.

Macrophages activation is crucial in pathogenesis of rheumatic diseases like ankylosing spondylitis (AS). Circular RNAs (circRNAs)-induced macrophage-associated inflammation participates in many autoimmune diseases but remains elusive in AS. Here, we verified increased expression of circIFNGR2 in peripheral blood mononuclear cells from patients with AS and its expression levels were correlated with the AS severity. In vitro assays revealed that circIFNGR2 enhances macrophage proliferation, and regulates M1/M2 macrophage polarization and NF-κB/Akt pathways. We identified that circIFNGR2 promoted the expression of iNOS/TNFα and M1 polarization, and restrained M2 polarization by sponging miR-939. Additionally, the RNA-binding protein, eIF4A3, was found to enhance the production of circIFNGR2. Interestingly, miR-939 attenuated joint damage in collagen-induced arthritis mice, whereas circIFNGR2 reversed this effect. Our findings highlight the pro-inflammatory roles of eIF4A3-induced circIFNGR2 in AS by modulating macrophage-associated inflammation through miR-939.

Effect of tibial rotation after uniplane medial open-wedge high tibial osteotomy in genu varum patients: An observational study.

The change in axial tibial rotation after uniplane medial open-wedge high tibial osteotomy (uniplane OWHTO) and its relevant influence factor is not known. Therefore, the aim of this study was to evaluate the change in axial tibial rotation after uniplane OWHTO, and the factors affecting tibia rotational change were analyzed. Between January 2022 and April 2022, the study was retrospectively conducted on genu varum patients who underwent uniplane OWHTO. In the weight-bearing anteroposterior long leg view, the hip-knee-ankle angle and medial proximal tibial angle (MPTA) were evaluated. The posterior tibial slope were measured from the lateral view. A CT scan of the knee joint was performed to evaluate the distal tibial rotation angle (TRA), femorotibial rotation angle and tibial tuberosity-trochlear groove distance. In addition, the foot morphology was assessed by the ankle deformity angle and ankle rotation angle using an angle measuring instrument. All parameters were measured preoperatively and 14 days after surgery. The mean change in hip-knee-ankle, MPTA was 10.5°±2.9°, 8.8°±2.6°. The mean preoperative and postoperative TRA were 25.1°±6.9° and 22.2°±6.2° respectively (P = .007). Thus, the mean ∆TRA was -3.0°±3.4° (IR) with a range of -9.6° to +2.8° after surgery. No significant differences were found in the femorotibial rotation angle and tibial tuberosity-trochlear groove distance before and after surgery (P > .05). The postoperative ankle rotation angle and ankle deformity angle changed significantly compared with preoperative values (P < .001). In the multiple regression analysis, ∆MPTA was the only predictor of distal tibial rotation (ß = 0.667, P = .003). The current study confirms an unintended internal rotation in the distal tibia following uniplane MOWHTO and the rotation in the distal tibia was influenced by the opening width. Surgeron should keep in mind to avoid the osteotomy complication leading to excessive rotation change during surgery.

Ropivacaine microsphere-loaded electroconductive nerve dressings for long-acting analgesia and functional recovery following diabetic peripheral nerve injury.

In recent years, electroconductive hydrogels (ECHs) have shown great potential in promoting nerve regeneration and motor function recovery following diabetic peripheral nerve injury (PNI), attributed to their similar electrical and mechanical characteristics to innate nervous tissue. It is well-established that PNI causes motor deficits and pain, especially in diabetics. Current evidence suggests that ropivacaine (ROP) encapsulated in poly lactic-co-glycolic acid (PLGA) microspheres (MSs) yield a sustained analgesic effect. In this study, an ECH electroconductive network loaded with MS/ROP (ECH-MS/ROP) was designed as a promising therapeutic approach for diabetic PNI to exert lasting analgesia and functional recovery. This dual delivery system allowed ROP's slow and sequential release, achieving sustained analgesia as demonstrated by our in vivo experiments. Meanwhile, this system was designed like a lamellar dressing, with desirable adhesive and self-curling properties, convenient for treating injured nerve tissues via automatically wrapping tube-like structures, facilitating the process of implantation. Our in vitro assays verified that ECH-MS/ROP was able to enhance the adhesion and motility of Schwann cells. Besides, both in vitro and in vivo studies substantiated that ECH-MS/ROP stimulated myelinated axon regeneration through the MEK/ERK signaling pathway, thereby improving muscular denervation atrophy and facilitating functional recovery. Therefore, this study suggests that the ECH-MS/ROP dressing provides a promising strategy for treating diabetic PNI to facilitate nerve regeneration, functional recovery and pain relief.

Comparison of the plantar pressure distribution and mechanical alignment in patients with varus knee osteoarthritis following high tibial osteotomy.

PURPOSE: The changes in the lower limb alignment were vitally important after high tibial osteotomy (HTO). Therefore, the purpose of present study was to analyze the characteristics of plantar pressure distribution after HTO, and to investigate the effect of plantar pressure distribution on postoperative limb alignment. METHODS: Between May 2020 and April 2021, varus knee patients undergoing HTO were evaluated in the present study. The peak pressure of plantar regions, medial-lateral pressure ratio (MLPR), foot progression angle (FTA), anteroposterior COP (AP-COP), lateral symmetry of COP (LS-COP), and the radiographic parameters were evaluated preoperatively and at the final follow-up. Compared among the slight valgus (SV), moderate valgus (MV) and large valgus (LV) groups at the final follow-up, the peak pressure of HM, HC and M5 regions, and the MLPR were compared; the Knee Injury and Osteoarthritis Outcome Score4 (KOOS4) including four subscales, and the American of orthopedic foot and ankle society (AOFAS) were evaluated. RESULTS: The WBL%, HKA and TPI angle changed significantly after HTO (P < 0.001). The preoperative group exhibited a lower peak pressure in the HM region (P < 0.05) and higher peak pressure in the M5 region (P < 0.05); the pre- and postoperative groups exhibited a lower peak pressure in the HC region (P < 0.05); the rearfoot MLPR was significantly lower and LS-COP was significantly higher in the preoperative group (P = 0.017 in MLPR and 0.031 in LS-COP, respectively). Comparison among the SV, MV and LV groups, the SV group indicated a lower peak pressure in the HM region (P = 0.036), and a lower MLPR in the rearfoot (P = 0.033). The KOOS Sport/Re score in the MV and LV groups increased significantly compared with the SV group (P = 0.042). CONCLUSION: Plantar pressure distribution during the stance phase in patients with varus knee OA following HTO exhibited a more medialized rearfoot plantar pressure distribution pattern than that before surgery. Compared with the small valgus alignment, a moderate to large valgus alignment allows patients to walk with a more even medial and lateral plantar pressure distribution, which is more similar to healthy adults.

Comparisons of in-hospital complications between total hip arthroplasty and hip resurfacing arthroplasty.

BACKGROUND: Hip resurfacing arthroplasty (HRA) is a less common but effective alternative method to total hip arthroplasty (THA) for hip reconstruction. In this study, we investigated the incidences of in-hospital complications between patients who had been subjected to THA and HRA. METHODS: The National Inpatient Sample data that had been recorded from 2005 to 2014 was used in this study. Based on the International Classification of Disease, Ninth Revision, Clinical Modification, patients who underwent THA or HRA were included. Data on demographics, preoperative comorbidities, length of hospital stay, total charges, and in-hospital mortality and complications were compared. Multiple logistic regression analysis was used to determine whether different surgical options are independent risk factors for postoperative complications. RESULTS: A total of 537,506 THAs and 9,744 HRAs were obtained from the NIS database. Patients who had been subjected to HRA exhibited less preoperative comorbidity rates, shorter length of stay and extra hospital charges. Moreover, HRA was associated with more in-hospital prosthesis loosening. Notably, patients who underwent HRA were younger and presented less preoperative comorbidities but did not show lower incidences in most complications. CONCLUSIONS: The popularity of HRA gradually reduced from the year 2005 to 2014. Patients who underwent HRA were more likely to be younger, male, have less comorbidities and spend more money on medical costs. The risk of in-hospital prosthesis loosening after HRA was higher. The HRA-associated advantages with regards to most in-hospital complications were not markedly different from those of THA. In-hospital complications of HRA deserve more attention from surgeons.

Tumour extracellular vesicles and particles induce liver metabolic dysfunction.

Cancer alters the function of multiple organs beyond those targeted by metastasis1,2. Here we show that inflammation, fatty liver and dysregulated metabolism are hallmarks of systemically affected livers in mouse models and in patients with extrahepatic metastasis. We identified tumour-derived extracellular vesicles and particles (EVPs) as crucial mediators of cancer-induced hepatic reprogramming, which could be reversed by reducing tumour EVP secretion via depletion of Rab27a. All EVP subpopulations, exosomes and principally exomeres, could dysregulate hepatic function. The fatty acid cargo of tumour EVPs-particularly palmitic acid-induced secretion of tumour necrosis factor (TNF) by Kupffer cells, generating a pro-inflammatory microenvironment, suppressing fatty acid metabolism and oxidative phosphorylation, and promoting fatty liver formation. Notably, Kupffer cell ablation or TNF blockade markedly decreased tumour-induced fatty liver generation. Tumour implantation or pre-treatment with tumour EVPs diminished cytochrome P450 gene expression and attenuated drug metabolism in a TNF-dependent manner. We also observed fatty liver and decreased cytochrome P450 expression at diagnosis in tumour-free livers of patients with pancreatic cancer who later developed extrahepatic metastasis, highlighting the clinical relevance of our findings. Notably, tumour EVP education enhanced side effects of chemotherapy, including bone marrow suppression and cardiotoxicity, suggesting that metabolic reprogramming of the liver by tumour-derived EVPs may limit chemotherapy tolerance in patients with cancer. Our results reveal how tumour-derived EVPs dysregulate hepatic function and their targetable potential, alongside TNF inhibition, for preventing fatty liver formation and enhancing the efficacy of chemotherapy.

Delayed surgery is associated with adverse outcomes in patients with hip fracture undergoing hip arthroplasty.

BACKGROUND: Hip arthroplasty (HA) is one of the most effective procedures for patients with hip fractures. The timing of surgery played a significant role in the short-term outcome for these patients, but conflicting evidence has been found. METHODS: The Nationwide Inpatient Sample database was investigated from 2002 to 2014 and identified 247,377 patients with hip fractures undergoing HA. The sample was stratified into ultra-early (0 day), early (1-2 days) and delayed (3-14 days) groups based on time to surgery. Yearly trends, postoperative surgical and medical complications, postoperative length of hospital stay (POS) and total costs were compared after propensity scores were matched between groups by demographics and comorbidity. RESULTS: From 2002 to 2014, the percentage of hip fracture patients who underwent HA increased from 30.61 to 31.98%. Early surgery groups showed fewer medical complications but higher surgical complications. However, specific complication evaluation showed both ultra-early and early groups decreased most of the surgery and medical complications with increasing post hemorrhagic anemia and fever. Medical complications were also reduced in the ultra-early group, but surgical complications increased. Early surgery groups reduced the POS by 0.90 to 1.05 days and total hospital charges by 32.6 to 44.9 percent than delayed surgery groups. Ultra-early surgery showed no benefit from POS than early group, but reduced total hospital charges by 12.2 percent. CONCLUSION: HA surgery performed within 2 days showed more beneficial effects on adverse events than delayed surgery. But surgeons should be cognizant of the potential increased risks of mechanical complications and post-hemorrhagic anemia.

Non-Coding-RNA-Activated Core/Chitosan Shell Nanounits Coated with Polyetheretherketone for Promoting Bone Regeneration and Osseointegration via Osteoimmunology.

Bone implant outcome and bone regeneration properties can be improved by the immunomodulation of exosomes (Exos) derived from bone marrow mesenchymal stem cells (BMSCs), which contain cytokines, signaling lipids, and regulatory miRNAs. Analysis of miRNAs in BMSCs-derived exosomes showed that miR-21a-5p exhibited the highest expression and was associated with the NF-κB pathway. Hence, we developed an implant with miR-21a-5p functionality to promote bone incorporation by immunoregulation. Mediated by the potent interaction between tannic acid (TA) and biomacromolecules, the tannic acid modified mesoporous bioactive glass nanoparticles coated with miR-21a-5p (miR-21a-5p@T-MBGNs) were reversibly attached to TA-modified polyetheretherketone (T-PEEK). Cocultured cells could phagocytose miR-21a-5p@T-MBGNs slowly released from miR-21a-5p@T-MBGNs loaded T-PEEK (miMT-PEEK). Moreover, miMT-PEEK boosted macrophage M2 polarization via the NF-κB pathway to increase BMSCs osteogenic differentiation. In vivo testing of miMT-PEEK in the rat air-pouch model and rat femoral drilling model indicated effective macrophage M2 polarization, new bone formation, and excellent osseointegration. Overall, the osteoimmunomodulation of the miR-21a-5p@T-MBGNs-functionalized implant promoted osteogenesis and osseointegration.

Exosomes-loaded electroconductive nerve dressing for nerve regeneration and pain relief against diabetic peripheral nerve injury.

Over the years, electroconductive hydrogels (ECHs) have been extensively applied for stimulating nerve regeneration and restoring locomotor function after peripheral nerve injury (PNI) with diabetes, given their favorable mechanical and electrical properties identical to endogenous nerve tissue. Nevertheless, PNI causes the loss of locomotor function and inflammatory pain, especially in diabetic patients. It has been established that bone marrow stem cells-derived exosomes (BMSCs-Exos) have analgesic, anti-inflammatory and tissue regeneration properties. Herein, we designed an ECH loaded with BMSCs-Exos (ECH-Exos) electroconductive nerve dressing to treat diabetic PNI to achieve functional recovery and pain relief. Given its potent adhesive and self-healing properties, this laminar dressing is convenient for the treatment of damaged nerve fibers by automatically wrapping around them to form a size-matched tube-like structure, avoiding the cumbersome implantation process. Our in vitro studies showed that ECH-Exos could facilitate the attachment and migration of Schwann cells. Meanwhile, Exos in this system could modulate M2 macrophage polarization via the NF-κB pathway, thereby attenuating inflammatory pain in diabetic PNI. Additionally, ECH-Exos enhanced myelinated axonal regeneration via the MEK/ERK pathway in vitro and in vivo, consequently ameliorating muscle denervation atrophy and further promoting functional restoration. Our findings suggest that the ECH-Exos system has huge prospects for nerve regeneration, functional restoration and pain relief in patients with diabetic PNI.

Robotic-assisted total knee arthroplasty is more advantageous for knees with severe deformity: a randomized controlled trial study design.

OBJECTIVE: A prospective, multicenter, randomized controlled trial was conducted to explore the short-term effect of a new robotic-assisted total knee arthroplasty (TKA) system, and the clinical and radiographic effectiveness between the robotic-assisted system and conventional TKA were compared and analyzed. MATERIALS AND METHODS: Overall, 144 patients were randomly divided into two groups, wherein 72 patients underwent TKA using the robotic­assisted system and 72 underwent conventional TKA. The demographic data and radiographic parameters of the patients were collected. The factors influencing postoperative hip-knee-ankle (HKA) angle deviation were determined by multiple linear regression. Clinical outcomes including postoperative Knee Society score, 10-cm visual analog scale, and range of motion (ROM) and radiographic results including the deviation value of coronal tibial component angle, coronal femoral component angle (CFCA), sagittal tibial component angle, sagittal femoral component angle (SFCA), and HKA angle as well as the rate of outliers in each angle were observed and compared between the two groups. RESULTS: The preoperative demographic data and imaging parameters, including Knee Society score, ROM, sex, surgical side, age, BMI, preoperative HKA angle, preoperative HKA angle deviation, and visual analog scale, showed no significant differences between groups. The robotic­assisted system group (RAS group) showed a postoperative malalignment of 3.2% for a mechanical axis higher than 3° and the conventional techniques group (CON group) showed a postoperative malalignment of 41.0% for a mechanical axis higher than 3°; the difference was statistically significant ( P <0.001). According to the results of multiple linear regression analysis, when the preoperative HKA angle deviation increased by 1°, the postoperative HKA angle deviation increased by 0.134° ( ß =0.134 min; 95% CI: 0.045-0.222). Therefore, patients were divided into a slight lower extremity alignment deviation group (preoperative HKA angle deviation <6°) and severe lower extremity alignment deviation group (preoperative HKA angle deviation ≥6°). For the patients with preoperatively slight lower extremity alignment deviation, the rate of postoperative HKA angle outlier in the RAS group was better than that in the CON group, and the operation duration in the RAS group was significantly longer than that in the CON group ( P <0.05). In the patients with a preoperative HKA angle deviation ≥6°, the rate of postoperative HKA angle and CFCA outliers in the RAS group was better than that in the CON group; the operation duration in the RAS group was significantly longer than that in the CON group, and the HKA angle deviation and CFCA deviation in the RAS group were significantly lower than those in the CON group ( P <0.05). No significant difference was observed in other indexes between the two groups ( P >0.05). CONCLUSION: This new robotic-assisted TKA system is safe and effective. The authors found that preoperative HKA angle deviation affects the postoperative HKA angle deviation. The robotic-assisted system has similar results to those reported by the traditional method with regard to restoring the mechanical axis of the leg and improving prosthesis alignment and clinical outcomes in patients with slight lower extremity alignment deviations preoperatively. For patients with severe preoperative lower extremity alignment deviations, the effectiveness in terms of the improvement in mechanical axis of the leg and prosthesis alignment were better with the robotic-assisted system, whereas the effectiveness of clinical outcomes was similar. A larger sample size and longer follow-up period are needed to determine whether the improved mechanical axis of the leg and prosthesis alignment observed with the robotic-assisted system can achieve better long-term radiographic and clinical outcomes.

A retrospective analysis of the incidence of postoperative delirium and the importance of database selection for its definition.

BACKGROUND: Postoperative delirium (POD) is a common complication after major surgery, resulting in various adverse reactions. However, incidence and risk factors associated with POD after shoulder arthroplasty (SA) have not been well studied using a large-scale national database. METHODS: A retrospective database analysis was performed based on the Nationwide Inpatient Sample (NIS) from 2005 to 2014, the largest fully paid hospital care database in the United States. Patients undergoing SA were included. The patient's demographics, comorbidities, length of stay (LOS), total costs, type of insurance, type of hospital, in-hospital mortality, and medical and surgical perioperative complications were assessed. RESULTS: A total of 115,147 SA patients were obtained from the NIS database. The general incidence of delirium after SA was 0.89%, peaking in 2010. Patients with delirium after SA had more comorbidities, prolonged LOS, increased hospitalization costs, and higher in-hospital mortality (P < 0.0001). These patients were associated with medical complications during hospitalization, including acute renal failure, acute myocardial infarction, pneumonia, pulmonary embolism, stroke, urinary tract infection, sepsis, continuous invasive mechanical ventilation, blood transfusion, and overall perioperative complications. Risk factors associated with POD include advanced age, neurological disease, depression, psychosis, fluid and electrolyte disturbances, and renal failure. Protective factors include elective hospital admissions and private insurance. CONCLUSION: The incidence of delirium after SA is relatively low. Delirium after SA was associated with increased comorbidities, LOS, overall costs, Medicare coverage, mortality, and perioperative complications. Studying risk factors for POD can help ensure appropriate management and mitigate its consequences. Meanwhile, we found some limitations of this type of research and the need to establish a country-based POD database, including further clearly defining the diagnostic criteria for POD, investigating risk factors and continuing to collect data after discharge (30 days or more), so as to further improve patient preoperative optimization and management.

Patients receiving knee arthroplasty with pre-existing long-term aspirin use suffer lower risk of perioperative complications but feel more postoperative pain.

BACKGROUND: Aspirin has gained increasing use-popularity on account of its multiple benefits. The present study aimed to investigate how a pre-existing long-term aspirin use (L-AU) would affect perioperative complications and postoperative pain in primary total knee arthroplasty (TKA) patients. METHODS: Utilizing the National Inpatient Sample (NIS) database, primary TKAs were divided into L-AU and non-L-AU cohorts. Propensity score matching (PSM) was performed to match the demographics and comorbidities characteristics. Chi-square test and logistic regression analysis were calculated for the risk analysis of perioperative complications and postoperative pain. RESULTS: The popularity of L-AU in primary TKA patients had significantly increased from 1.5% (2005) to 10.5% (2014) in the U.S. Pre-existing L-AU was associated with decreased risks of most perioperative complications (any complication, adjusted odds ratio [aOR]: 0.920), in-hospital mortality (aOR: 0.367), and shortened hospitalization stay (LOS) (aOR: 0.647), etc. However, L-AU was recognized as a risk factor of acute postoperative pain (aOR: 1.466) and slightly higher total cost (aOR: 1.047). CONCLUSIONS: For the first time in the present study, it is found that pre-existing long-term aspirin use is benefic in reducing perioperative complication risk. According to this finding, future research might determine the optimal pre-operational taking time and dose of aspirin use. Consequently, orthopedic surgeons and healthcare providers could provide this valuable advice to specific patients prior to a planned arthroplasty and subsequently gain feasible clinical benefits.

An all-silk-derived bilayer hydrogel for osteochondral tissue engineering.

Osteochondral repair remains a challenge in clinical practice nowadays despite extensive advances in tissue engineering. The insufficient recruitment of endogenous cells in the early stage and incomplete cell differentiation in the later stage constitute the major difficulty of osteochondral repair. Here, a novel all-silk-derived multifunctional biomaterial platform for osteochondral engineering is reported. The bilayer methacrylated silk fibroin (SilMA) hydrogel was fabricated through stratified photocuring as the basic provisional matrix for tissue regeneration. Platelet-rich plasma (PRP) incorporation promoted the migration and pre-differentiation of the bone marrow mesenchymal stem cells (BMSCs) in the early stage of implantation. The long-term regulation of BMSCs chondrogenesis and osteogenesis was realized by the stratified anchoring of the silk fibroin (SF) microspheres respectively loaded with Kartogenin (KGN) and berberine (BBR) in the hydrogel. The composite hydrogels were further demonstrated to promote BMSCs chondrogenic and osteogenic differentiation under an inflammatory microenvironment and to achieve satisfying cartilage and subchondral bone regeneration with great biocompatibility after 8 weeks of implantation. Since all the components used are readily available and biocompatible and can be efficiently integrated via a simple process, this composite hydrogel scaffold has tremendous potential for clinical use in osteochondral regeneration.

Complications of primary total hip arthroplasty among patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and primary osteoarthritis.

BACKGROUND: Limited information exists comparing the perioperative complications of the different inflammatory arthropathies (IAs) after total hip arthroplasty (THA). Our study was aimed to (1) compare perioperative complications and (2) determine the most common complications between the different IA subtypes compared with patients with primary osteoarthritis (OA) undergoing primary THA and (3) find whether the difference in postoperative complications also exists between different IA after THA. METHODS: The Nationwide Inpatient Sample (NIS) was used to identify patients with Rheumatoid arthritis (RA), psoriatic arthritis, ankylosing spondylitis (AS), and primary OA undergoing unilateral THA between 2005 and 2014. Preoperative diagnosis, comorbidities, and postoperative complications were determined using the International Classification of Disease Clinical Modification version 9 codes. The prevalence of perioperative complications was compared between patients with IA and primary OA and between patients with different IA. RESULTS: When compared with patients with primary OA, patients with RA had significantly more postoperative surgical and medical complications. Yet there are just several medical complications differences exist between PA and primary OA or AS and primary OA, including stroke and acute renal failure for psoriatic arthritis and urinary tract infection and pneumonia for AS. What is more, there were also several differences in perioperative medical complications seen in patients with different IA. CONCLUSION: Except for patients with RA, the differences in perioperative complications was small between patients with IA and primary OA and between patients with different types of IA.

Spontaneous resolution of asymptomatic alumina matrix composite ceramic liner dissociation: a case report.

BACKGROUND: Total hip arthroplasty(THA)is widely used to treat end-stage hip disorders. Ceramic-on-ceramic total hip prostheses are widely used because of their durability. Alumina matrix composite (AMC), known as the fourth-generation ceramics, reduces implant fracture and wear rate compared to their predecessors. However, ceramic acetabular liner dissociation is a complication that necessitates revision of the AMC prostheses. To date, only few cases of AMC liner dissociation have been reported and all of which have been treated with revision surgery. Therefore, the prognosis of non-operated AMC liner dissociation remains unknown so far. CASE PRESENTATION: A 57-year-old man with avascular necrosis of the femoral head was treated with THA, wherein a Pinnacle® (DePuy, J&J, Warsaw, IN) acetabular cup and AMC liner were implanted. Intraoperative examination confirmed proper seating of the liner, whereas the initial postoperative radiograph revealed liner dissociation. The patient refused surgical revision due to the absence of symptoms and was discharged and followed-up. The patient made an uneventful recovery, and radiographic follow-up at 6-month post-operation showed that the liner was re-seated to its right position. No clinical or radiographic anomaly was found at the 15-month of postoperative follow-up. CONCLUSIONS: Here, we report an unprecedented case of AMC ceramic liner dissociation with spontaneous resolution. This case shows that ceramic liner dissociation could be asymptomatic, and careful postoperative examination of the patient is important. Spontaneous resolution is possible, but the underlying mechanism and the eligible patient to benefit from it must be investigated. Before clarifying these questions, revision surgery should be the first-line treatment.

A Mid-term Follow-up Study on the Reimplantation of Autoclaved Femoral and Tibial Components as Spacers for Treating Infected Total Knee Arthroplasty.

OBJECTIVE: Infection after total knee arthroplasty (TKA) is a rare but devastating complication. Different types of spaces have been used in two-stage revision. The study aimed to evaluate the effect of autoclaved femoral and tibial components as spacers for treating periprosthetic infections after TKA. METHODS: A retrospective study was performed for 13 patients (five males, eight females) with a mean age of 69 ± 6 (range, 57-80) years and suffering from periprosthetic infection after TKA. They were treated with unconventional two-stage revision from May 2008 to June 2017. In the first-stage surgery, the autoclaved femoral and tibial components were reimplanted with a new liner as a spacer after a thorough debridement. After 4-6 months, the second-stage surgery was performed according to the patients' requirements. The knee society score (KSS) and knee range of motion (ROM) were assessed before and after surgery. The reinfection rate was calculated. RESULTS: The mean duration of follow-up was 5.7 ± 2.1 (range, 3.1-8.8) years. Culture-positive infections comprised 69% of the cohort. All patients were able to walk 24 h after the first stage surgery, and the knee ROM could reach 90° in 1 week. Two patients (15.4%) experienced an infection recurrence. One patient was reinfected 1 year after the first stage surgery. Another patient developed reinfection 3 years after surgery but did not choose re-revision and died of pneumonia. Only one patient underwent the second stage revision. The remaining 10 patients refused to receive a new prosthesis. At the time of the final follow-up, six patients had slight pain in the knee while walking, and one patient required crutches to walk. There were no signs of prosthesis dislocation, rupture, deep vein thrombosis, pulmonary embolism, or delayed wound healing. No radiolucent lines or osteolysis were found. The mean KSS improved from 51 ± 10 (range, 35-63) points preoperatively to 79 ± 5 (range, 60-85) points at the final follow-up. The average ROM before and after the first stage surgery were 62° ± 29° (range, 10°-100°) and 104° ± 9° (range, 90°-120°) (t = 4.659, P < 0.01) respectively. The infection control rate was 84.6%. CONCLUSION: Reimplantation of the autoclaved original femoral and tibial components as an articulating spacer during the first stage surgery is a valuable addition for treating an infected TKA.