Background: With the development of population aging worldwide, sarcopenia and knee osteoarthritis (KOA), two age-related diseases, will continue to impose increasing medical and economic burdens on the society. Previous studies have discovered an association between the two, but the causality remains controversial, and it is difficult to eliminate confounding factors. Therefore, a Mendelian randomization (MR) study was conducted to overcome these confounding factors and investigate the causal relationship between sarcopenia and KOA. Objective: The present work focused on assessing the causality between KOA and sarcopenia, so as to provide new strategies to prevent and treat these two conditions in clinic. Methods: We registered the title with PROSPERO (ID: CRD42023421096). The two-sample bidirectional MR analysis was conducted in two steps, with sarcopenia being the exposure whereas KOA being the outcome in the first step, and vice versa in the second step. Genome-wide association studies (GWAS) data on low hand-grip strength (n=256,523), walking pace (n=459,915), appendicular lean mass (ALM, n=450,243), and KOA (n=403,124) were obtained from the UK Biobank. Methods such as the inverse variance weighted (IVW) and weighted median were utilized for assessing the causality of KOA with sarcopenia, and sensitivity analyses were also conducted. Results: In the main MR analysis using the IVW method, evidence suggested that low hand-grip strength, walking pace, and ALM had adverse effects on KOA (p-value 0.0001, odds ratio (OR) 1.4569, 95% confidence interval (CI) 1.2007– 1.7677 for low hand-grip strength; p-value 0.0003, OR 1.1500, 95% CI 1.050– 1.183 for ALM; p-value 5.29E-19, OR 0.0932, 95% CI 0.0553– 0.1572 for walking pace). However, there was no causality of KOA with sarcopenia in the opposite direction. Conclusion: Our study suggests an obvious unidirectional causality of KOA with sarcopenia, and supports the notion that patients with sarcopenia are more susceptible to the development of KOA.

Background: Acupuncture has been widely used in the clinical management of osteoarthritis of the knee (KOA). Many systematic reviews (SRs) and meta-analyses (MAs) have reported its effectiveness in relieving pain. This overview aimed to summarize SRs and MAs on the effectiveness and safety of acupuncture for KOA and evaluate their methodological and evidence quality of the included SRs and MAs. Methods: We conducted a comprehensive literature search for SRs and MAs in four Chinese and four international databases from their inception until August 2021. Two researchers independently searched the reviews, extracted the data, and cross-checked the data. The Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR 2) tool was used to evaluate the methodological quality of the included SRs and MAs. The Grades of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used to assess the quality of evidence for the outcomes of the included SRs and MAs. Results: A total of 14 SRs and MAs were included. The evaluation results of the AMSTAR 2 tool showed that the methodological quality of all the 14 SRs and MAs was critically low. The principal causes are the lack of a pre-registration proposal and a list of excluded studies and justify the exclusions, the report on the sources of funding, and the reasons for the study designs for inclusion. The results of the GRADE evaluation showed 25 of 46 outcomes were very low-level evidence. Seventeen were of low level, four were of moderate level and none were of high level. Most outcomes were downgraded in quality of evidence mainly because of publication bias and imprecision. Conclusion: The existing evidence suggests that acupuncture seems to be an effective and safe therapy for KOA. However, the deficiencies in the methodological quality and quality of evidence of the included SRs/MAs have limited the reliability of the conclusions. Therefore, further rigorous and comprehensive studies are warranted to verify the effectiveness and safety of acupuncture in KOA.

Background: Osteochondral defects mostly occur as a result of trauma or articular degeneration. The poor regenerative ability of articular cartilage remains osteochondral defects are a tricky problem to deal with. The modern treatment strategies mainly focus on cartilage tissue engineering with bioactive materials. In this study, we aimed to develop icariin conditioned serum (ICS) together with hyaluronic acid (HA) and determine their ability in reparing osteochondral tissue in a critical-sized defect in rabbit knees. Methods: Primary chondrocytes were incubated with serum conditioned with icariin at different concentrations, then cell proliferation rates and glycosaminoglycan (GAG) secretion were detected. Rabbits were treated with intra-articular injection of 0.5 mL normal saline (NS), ICS, HA and ICS + HA in the right knee joint, respectively. ICRS scores were used to assess the macroscopic cartilage regeneration. Histological and immunohistochemical analysis including H&E, Safranin O, toluidine blue and collagen II staining were used to determine the repair of cartilage and the regeneration of chondrocytes. Results: Icariin at a low dose of 0.94 g/kg was identified to have significantly promoted the proliferation of chondrocytes and enhance the secretion of GAG. Femoral condyle from rabbits treated by ICS together with HA was observed to be integrated with native cartilage and more subchondral bone regeneration. ICS together with HA could promote repair of the cartilage defect and increase the neoformation of cartilage. Conclusions: These results demonstrated the potential of ICS combined with HA to promote reparative response in cartilage defects and the possible application in bioactive material based cartilage regeneration therapies.

Background: Knee Osteoarthritis (KOA) has become a serious health issue for elderly patients. Several systematic reviews (SRs) have reported Tai Chi has widely been used in the treatment of KOA. However, the methodology and conclusions of these SRs are controversial. This overview aims to summarize and evaluate the available evidence for the efficacy and safety of Tai Chi for KOA. Methods: Two independent researchers searched eight databases from the inception to April 30, 2022. The included SRs were assessed respectively by A Measurement Tool to Assess Systematic Reviews (AMSTAR) 2, the Risk of Bias in Systematic Reviews (ROBIS) tool, and the Preferred Reporting Item for Systematic Review and Meta-analysis (PRISMA) statement. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was used to assess the quality of the included SRs in terms of outcome indicators. Results: Six SRs were finally included in this overview. The results of methodological quality, reporting quality, and risk of bias of the included SRs were generally unsatisfactory. The limitations were a lack of explaining the reasons for selection, a list of excluded literature, reporting bias assessment, and reporting the potential sources of conflict of interest. In addition, only 1 item was assessed as moderate quality by using the GRADE tool. Limitations were the most common downgraded factors. Conclusion: Tai Chi is effective as a non-pharmacological intervention in the integrative treatment of KOA. However, the quality of evidence and methodological quality of SRs is generally unsatisfactory, suggesting that these results must be interpreted with caution. Trial Registration/Protocol Registration: PROSPERO registration number: CRD42022315146.

Aim: This study is to investigate the effects of umbilical cord mesenchymal stem cells (UCMSCs) loaded with the graphene oxide (GO) granular lubrication on ameliorating inflammatory responses and osteoporosis of the subchondral bone in knee osteoarthritis (KOA) animal models.Methods: The KOA animal models were established using modified papain joint injection. 24 male New Zealand rabbits were classified into the blank control group, GO group, UCMSCs group, and GO + UCMSCs group, respectively. The concentration in serum and articular fluid nitric oxide (NO), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), type II collagen (COL-II), and glycosaminoglycan (GAG) was detected using ELISA, followed by the dissection of femoral condyles and staining of HE and Micro-CT for observation via the microscope.Results: GO granular lubrication and UCMSCs repaired the KOA animal models. NO, IL-6, TNF-α, GAG, and COL-II showed optimal improvement performance in the GO + UCMSCs group, with statistical significance in contrast to the blank group (P <0.01). Whereas, there was a great difference in levels of inflammatory factors in serum and joint fluid. Micro-CT scan results revealed the greatest efficacy of the GO + UCMSCs group in improving joint surface damage and subchondral bone osteoporosis. HE staining pathology for femoral condyles revealed that the cartilage repair effect in GO + UCMSCs, UCMSCs, GO, and blank groups were graded down.Conclusion: UCMSCs loaded with graphene oxide granular lubrication can promote the secretion of chondrocytes, reduce the level of joint inflammation, ameliorate osteoporosis of the subchondral bone, and facilitate cartilage repair.