Background: Whether resurface the patella or not in total knee arthroplasty (TKA) was controversial. In 2013, we conducted a meta-analysis of randomized controlled trials (RTCs). After that, plenty of studies have been carried out, but there still existed a great deal of controversy. In order to update our previous study, we conducted this update meta-analysis to evaluate the efficacy of patellar resurfacing in TKA.Methods: Databases were searched for RCTs comparing the outcomes of patellar resurfacing and nonresurfacing in TKA. Outcomes of knee relevant indicators were analysed. To see the short- and long-term effects, we calculated the data in total and divided the patients who were followed up for ≤ 3 years and ≥ 5 years into two subgroups as well.Results: Thirty-two trials assessing 6887 knees were eligible. There was a significant difference in terms of reoperation (in total and ≥ 5 years), Knee Society Score (KSS), function score (in total and ≥ 5 years) and noise. While no significant difference was found in the following items: reoperation (≤ 3 years), anterior knee pain (AKP), function score (≤ 3 years), range of motion (ROM), Oxford score, the Knee Injury and Osteoarthritis Outcome Score (KOOS), visual analogue score (VAS), Feller score, patellar tilt and the patients’ satisfaction.Conclusions: We found that patellar resurfacing could reduce the occurrence of reoperation and noise after surgery, as well as increase the KSS and function score, while it might not influence the outcomes such as AKP, ROM, Oxford score, KOOS, VAS, Feller score, patellar tilt and the patients’ satisfaction. The results are different from our previous finding in the meta-analysis. In conclusion, we prefer patellar resurfacing in TKA.

Background: To explore the influencing factors of perioperative hidden blood loss in intertrochanteric fractures. Method: We undertook a retrospective analysis from January 2016 to October 2019. Clinical data of 118 patients with intertrochanteric fractures were included. Hidden blood loss was calculated from the haematocrit changes before and after surgery using the Gross equation based on height, weight, and haematocrit (HCT) changes before and after surgery. Patients’ gender, age, presence of underlying diseases, fracture types, anaesthesia methods, time from injury to surgery, administration of antiplatelet drugs within 6 months before surgery, use of anticoagulant drugs after surgery, and bone density were statistically analysed. Factors having an effect on hidden blood loss were screened out. Then, hidden blood loss was used as the dependent variable, and each influencing factor was used in turn as the independent variable. Multivariate linear regression analysis was employed to analyse the related risk factors that affect hidden blood loss during the perioperative period of patients with intertrochanteric fractures. Result: The apparent blood loss during the operation was 203.81 ±105. 51 ml, and the hidden blood loss was 517.55±191.47 ml. There were significant differences in the hidden blood loss of patients with different fracture types (stable vs unstable), anaesthesia methods (general anaesthesia vs intraspinal anaesthesia), antiplatelet or postoperative anticoagulant drugs, and bone densities (P< 0.05). 05). Multiple linear regression analysis showed that internal fixation, age, fracture type, anaesthesia method, anticoagulant application, and bone density were related risk factors that affected hidden blood loss during the surgical treatment of intertrochanteric fractures. Conclusion: Hidden blood loss is the main cause of perioperative blood loss in intertrochanteric fractures, and the risk factors for hidden blood loss include internal fixation, fracture type (e.g., unstable), anaesthesia (e.g., intraspinal), and use of anticoagulant drugs. Specifically, we found that low bone density was a risk factor for hidden blood loss. It is not reliable to use apparent blood loss as the basis for fluid replacement and transfusion. We must fully consider the existence of hidden blood loss and intervene as soon as possible to prevent complications. Level of evidence: III

Background: Hemorheological parameters have been confirmed to be related with deep vein thrombosis (DVT). This study is aimed to verify whether preoperative erythrocyte electrophoresis exponent was associated with postoperative deep vein thrombosis (DVT) risk after total knee arthroplasty (TKA) in patients with primary knee osteoarthritis (KOA). Methods: From March 2010 to May 2020, a total of 750 consecutive KOA patients who accepted unilateral TKA were enrolled. They were divided into DVT (176 patients) and non-DVT groups (574 patients) according to the examination results of the Doppler ultrasound of deep veins in both lower limbs on postoperative day 3. The Chi-square test, Student’s t test, and multivariate logistic regression analysis were performed to analyze the correlation of erythrocyte electrophoresis exponent and DVT risk in 2 groups. Receiver operating characteristic (ROC) analysis was used to assess predictive value of erythrocyte electrophoresis exponent for DVT. Results: A low erythrocyte electrophoresis exponent was a significant risk factor for DVT in patients with primary KOA (p < 0.05), especially in females when stratified by gender (p < 0.05). Conclusions: The findings suggest that lower erythrocyte electrophoresis before surgery may be independently associated with a higher post-surgery DVT risk in primary KOA patients. It is necessary to optimize prophylaxis strategies for DVT in these patients.

Intervertebral disc degeneration (IDD) is a common musculoskeletal disease that develops with increasing age. However, the exact occurrence and progression of IDD remains unclear. Gene expression profiles were downloaded from the Gene Expression Omnibus (GEO) repository. The NCBI GEO2R analysis tool was used to identify differentially expressed genes. The protein-protein interaction (PPI) network was predicted using the STRING website and visualized using the Cytoscape software. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed to enrich GO terms and signaling pathways using the Metascape database. To identify potential upstream miRNA targets of these differentially expressed genes, the mRNA-miRNA interaction networks were predicted by Network Analyst database. To identify the 2 key genes with significant differences among the 10 hub genes, the GraphPad Prism Tool and GeneCards database were used for analysis. 22 genes were identified. A PPI network was constructed and the other 30 related genes were deduced. GO and Kyoto Encyclopedia of Genes and Genomes enrichment networks indicated extracellular matrix organization, collagen-containing extracellular matrix and extracellular matrix structural constituent in extracellular matrix (ECM) regulation in IDD. The mRNA-miRNA interaction networks suggested that many miRNAs could regulate autophagy-related genes individually and collectively. The GraphPad Prism Tool and GeneCards database analysis results suggested that 2 hub genes were involved in IDD. Our results revealed that the role of ECM could be a regulatory mechanism in IDD and that these ECM-related genes might be targets for the intervention of IDD.