Guidelines for the diagnosis and treatment of osteoarthritis in China (2019 edition)

[Finite element analysis of the impact of bone mass and volume of low-density area under tibial plateau on lower limb alignment]

Objective

To investigate the impact of the bone mass and volume of the low-density area under the tibial plateau on the lower limb force line by finite element analysis, offering mechanical evidence for preventing internal displacement of the lower limb force line in conjunction with knee varus in patients with knee osteoarthritis (KOA) and reducing bone mass under the tibial plateau.

Methods

A healthy adult was selected as the study subject, and X-ray film and CT imaging data were acquired. Mimics 21.0 software was utilized to reconstruct the complete knee joint model and three models representing low-density areas under the tibial plateau with equal volume but varying shapes. These models were then imported into Solidworks 2023 software for assembly and verification. Five KOA finite element models with 22%, 33%, 44%, 55%, and 66% bone mass reduction in the low-density area under tibial plateau and 5 KOA finite element models with 81%, 90%, 100%, 110%, and 121% times of the low-density area model with 66% bone mass loss were constructed, respectively. Under physiological loading conditions of the human lower limb, the distal ends of the tibia and fibula were fully immobilized. An axial compressive load of 1 860 N, following the lower limb force line, was applied to the primary load-bearing area on the femoral head surface. The maximum stress within the tibial plateau, as well as the maximum displacements of the tibial cortical bone and tibial subchondral bone, were calculated and analyzed using the finite element analysis software Abaqus 2022. Subsequently, predictions regarding the alteration of the lower limb force line were made based on the analysis results.

Results

The constructed KOA model accorded with the normal anatomical structure of lower limbs. Under the same boundary conditions and the same load, the maximum stress of the medial tibial plateau, the maximum displacement of the tibial cortical bone and the maximum displacement of the cancellous bone increased along with the gradual decrease of bone mass in the low-density area under the tibial plateau and the gradual increase in the volume of the low-density area under tibial plateau, with significant differences ( P<0.05).

Conclusion

The existence of a low-density area under tibial plateau suggests a heightened likelihood of knee varus and inward movement of the lower limb force line. Both the volume and reduction in bone mass of the low-density area serve as critical initiating factors. This information can provide valuable guidance to clinicians in proactively preventing knee varus and averting its occurrence.

Appraisal of quality and analysis of the similarities and differences between osteoarthritis Clinical Practice Guideline recommendations: A systematic review

OBJECTIVE

Clinical Practice Guidelines (CPGs) aim to support management of hip and knee osteoarthritis (OA), but recommendations are often conflicting and implementation is poor, contributing to evidence-to-practice gaps. This systematic review investigated the contextual and methodological factors contributing to conflicting recommendations for hip and knee OA.

METHOD

Our systematic review appraised CPGs for managing hip and knee OA in adults ≥18 years (PROSPERO CRD42021276635). We used AGREE-II and AGREE-REX to assess quality and extracted data on treatment gaps, conflicts, biases, and consensus. Heterogeneity of recommendations was determined using Weighted Fleiss Kappa (K). The relationship between (K) and AGREE-II/AGREE-REX scores was explored.

RESULTS

We identified 25 CPGs across eight countries and four international organisations. The ACR, EULAR, NICE, OARSI and RACGP guidelines scored highest for overall AGREE-II quality (83%). The highest overall AGREE-REX scores were for BMJ Arthroscopy (80%), RACGP (78%) and NICE (76%). CPGs with the least agreement for pharmacological recommendations were ESCEO and NICE (-0.14), ACR (-0.08), and RACGP (-0.01). The highest agreements were between RACGP and NICE (0.53), RACGP and ACR (0.61), and NICE and ACR (0.91). Decreased internal validity determined by low-quality AGREE scores(<60%) in editorial independence were associated with less agreement for pharmacological recommendations.

CONCLUSION

There were associations between guideline quality and agreement scores. Future guideline development should be informed by robust evidence, editorial independence and methodological rigour to ensure a harmonisation of recommendations. End-users of CPGs must recognise the contextual factors associated with the development of OA CPGs and balance these factors with available evidence.

TMF inhibits extracellular matrix degradation by regulating the C/EBPβ/ADAMTS5 signaling pathway in osteoarthritis

Osteoarthritis (OA) is a chronic joint disease, characterized by degenerative destruction of articular cartilage. Chondrocytes, the unique cell type in cartilage, mediate the metabolism of extracellular matrix (ECM), which is mainly constituted by aggrecan and type II collagen. A disintegrin and metalloproteinase with thrombospondin 5 (ADAMTS5) is an aggrecanase responsible for the degradation of aggrecan in OA cartilage. CCAAT/enhancer binding protein β (C/EBPβ), a transcription factor in the C/EBP family, has been reported to mediate the expression of ADAMTS5. Our previous study showed that 5,7,3',4'-tetramethoxyflavone (TMF) could activate the Sirt1/FOXO3a signaling in OA chondrocytes. However, whether TMF protected against ECM degradation by down-regulating C/EBPβ expression was unknown. In this study, we found that aggrecan expression was down-regulated, and ADAMTS5 expression was up-regulated. Knockdown of C/EBPβ could up-regulate aggrecan expression and down-regulate ADAMTS5 expression in IL-1β-treated C28/I2 cells. TMF could compromise the effects of C/EBPβ on OA chondrocytes by activating the Sirt1/FOXO3a signaling. Conclusively, TMF exhibited protective activity against ECM degradation by mediating the Sirt1/FOXO3a/C/EBPβ pathway in OA chondrocytes.

Osteoarthritis: Insights into Diagnosis, Pathophysiology, Therapeutic Avenues, and the Potential of Natural Extracts

Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable research strides. Presently, diagnosis heavily relies on clinician expertise and meticulous differential diagnosis to exclude other joint-affecting conditions. Therapeutic approaches for OA predominantly focus on patient education for self-management alongside tailored exercise regimens, often complemented by various pharmacological interventions primarily targeting pain alleviation. However, pharmacological treatments typically exhibit short-term efficacy and local and/or systemic side effects, with prosthetic surgery being the ultimate resolution in severe cases. Thus, exploring the potential integration or substitution of conventional drug therapies with natural compounds and extracts emerges as a promising frontier in enhancing OA management. These alternatives offer improved safety profiles and possess the potential to target specific dysregulated pathways implicated in OA pathogenesis, thereby presenting a holistic approach to address the condition's complexities.

Automatic measurement of lower limb alignment in portable devices based on deep learning for knee osteoarthritis

BACKGROUND

For knee osteoarthritis patients, analyzing alignment of lower limbs is essential for therapy, which is currently measured from standing long-leg radiographs of anteroposterior X-ray (LLR) manually. To address the time wasting, poor reproducibility and inconvenience of use caused by existing methods, we present an automated measurement model in portable devices for assessing knee alignment from LLRs.

METHOD

We created a model and trained it with 837 conforming LLRs, and tested it using 204 LLRs without duplicates in a portable device. Both manual and model measurements were conducted independently, then we recorded knee alignment parameters such as Hip knee ankle angle (HKA), Joint line convergence angle (JCLA), Anatomical mechanical angle (AMA), mechanical Lateral distal femoral angle (mLDFA), mechanical Medial proximal tibial angle (mMPTA), and the time required. We evaluated the model's performance compared with manual results in various metrics.

RESULT

In both the validation and test sets, the average mean radial errors were 2.778 and 2.447 (P<0.05). The test results for native knee joints showed that 92.22%, 79.38%, 87.94%, 79.82%, and 80.16% of the joints reached angle deviation<1° for HKA, JCLA, AMA, mLDFA, and mMPTA. Additionally, for joints with prostheses, 90.14%, 93.66%, 86.62%, 83.80%, and 85.92% of the joints reached that. The Chi-square test did not reveal any significant differences between the manual and model measurements in subgroups (P>0.05). Furthermore, the Bland-Altman 95% limits of agreement were less than ± 2° for HKA, JCLA, AMA, and mLDFA, and slightly more than ± 2 degrees for mMPTA.

CONCLUSION

The automatic measurement tool can assess the alignment of lower limbs in portable devices for knee osteoarthritis patients. The results are reliable, reproducible, and time-saving.

Identification of key genes and immune infiltration in osteoarthritis through analysis of zinc metabolism-related genes

BACKGROUND

Osteoarthritis (OA) represents a prominent etiology of considerable pain and disability, and conventional imaging methods lack sensitivity in diagnosing certain types of OA. Therefore, there is a need to identify highly sensitive and efficient biomarkers for OA diagnosis. Zinc ions feature in the pathogenesis of OA. This work aimed to investugate the role of zinc metabolism-related genes (ZMRGs) in OA and the diagnostic characteristics of key genes.

METHODS

We obtained datasets GSE169077 and GSE55235 from the Gene Expression Omnibus (GEO) and obtained ZMRGs from MSigDB. Differential expression analysis was conducted on the GSE169077 dataset using the limma R package to identify differentially expressed genes (DEGs), and the intersection of DEGs and ZMRGs yielded zinc metabolism differential expression-related genes (ZMRGs-DEGs). The clusterProfiler R package was employed for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of ZMRGs-DEGs. Potential small molecule drugs were predicted using the CMap database, and immune cell infiltration and function in OA individuals were analyzed using the ssGSEA method. Protein-protein interaction (PPI) networks were constructed to detect Hub genes among ZMRGs-DEGs. Hub gene expression levels were analyzed in the GSE169077 and GSE55235 datasets, and their diagnostic characteristics were assessed using receiver operating characteristic (ROC) curves. The gene-miRNA interaction network of Hub genes was explored using the gene-miRNA interaction network website.

RESULTS

We identified 842 DEGs in the GSE169077 dataset, and their intersection with ZMRGs resulted in 46 ZMRGs-DEGs. ZMRGs-DEGs were primarily enriched in functions such as collagen catabolic processes, extracellular matrix organization, metallopeptidase activity, and pathways like the IL-17 signaling pathway, Nitrogen metabolism, and Relaxin signaling pathway. Ten potential small-molecule drugs were predicted using the CMap database. OA patients exhibited distinct immune cell abundance and function compared to healthy individuals. We identified 4 Hub genes (MMP2, MMP3, MMP9, MMP13) through the PPI network, which were highly expressed in OA and demonstrated good diagnostic performance. Furthermore, two closely related miRNAs for each of the 4 Hub genes were identified.

CONCLUSION

4 Hub genes were identified as potential diagnostic biomarkers and therapeutic targets for OA.

The effects of manual therapy in pain and safety of patients with knee osteoarthritis: a systematic review and meta-analysis

BACKGROUND

Manual therapy (MT) is frequently used in combination with management of osteoarthritis of the knee, but there is no consensus on the exact efficacy of this treatment strategy. The purpose of this systematic review and meta-analysis was to evaluate the pain relief and safety of MT for treatment of knee osteoarthritis (KOA).

METHODS

Randomized controlled trials evaluating MT in patients with KOA in major English and Chinese journals were searched in the following databases: Wanfang, China Science and Technology Journal Database (VIP database), China National Knowledge Infrastructure (CNKI), PubMed, Embase, Web of Science, and the Cochrane Library databases through June 2023. The methodological quality and quality of evidence of the included studies were assessed using Cochrane's risk-of-bias 2 (ROB 2) tool and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. Data analysis was performed using Stata version 15.0 software. After use of Galbraith plots to exclude studies that could lead to heterogeneity, random effects models were used to analyze the remaining data and test the consistency of the findings. We used meta-regression to assess the effect of treatment period, patient age, and sex ratio on outcomes. Funnel plots and Egger's test were used to evaluate publication bias. Sensitivity analyses were used to determine the reliability of the results.

RESULTS

A total of 25 studies, with 2376 participants, were included in this review. The overall methodological quality of the included studies was limited. Our findings suggest that MT has a positive impact on pain relief outcomes in KOA patients. The meta-analysis showed that MT was superior to usual care (SMD = 2.04, 95% CI 0.94, 3.14, I 2 = 96.3%; low evidence quality) and exercise (SMD = 1.56, 95% CI 0.41, 2.71, I 2 = 96.3%; low evidence quality) for reducing pain. In terms of improvement in visual analogue scale (VAS) scores, MT treatment beyond 4 weeks (SMD = 1.56, 95% CI 0.41, 2.71, I 2 = 96.3%) may be superior to treatments less than or equal to 4 weeks (SMD = 1.24, 95% CI 0.56, 1.95, I 2 = 94.7%). No serious adverse events associated with MT were reported.

CONCLUSIONS

MT may be effective at reducing pain in patients with KOA and may be more effective after a 4-week treatment period. Compared with usual care and exercise therapy, MT may be superior at reducing KOA pain in the short term (9 weeks), but its long-term efficacy requires careful consideration of evidence-based outcomes. MT appears to be safe for KOA patients, though clinicians should inform patients of the potential risk of MT-related adverse events.

HSPB1 as an RNA-binding protein mediates the pathological process of osteoarthritis

Heat-shock protein beta1 (HSPB1) is a member of the small HSP family, downregulated in osteoarthritis (OA) chondrocytes and demonstrated the capacity to serve as an RNA-binding protein (RBP). This work aimed to explore the profile of HSPB1 bound RNA and reveal the potential regulation mechanism of HSPB1 in OA. In this work, we captured an unbiased HSPB1-RNA interaction map in Hela cells using the iRIP-seq. The results demonstrated that HSPB1 interacted with plentiful of mRNAs and genomic location toward the CDS region. Functional enrichment of HSPB1-related peaks showed the involvement in gene expression, translation initiation, cellular protein metabolic process, and nonsense-mediated decay. HOMER software analysis showed that HSPB1 bound peaks were over-represented in GAGGAG sequences. In addition, ABLIRC and CIMS algorithm indicated that HSPB1 bound to AU-rich motifs and the proportion of AU-rich peaks in 3' UTR were slightly higher than that in other regions. Moreover, HSPB1-binding targets analysis revealed several gens were associated with OA including EGFR, PLEC, COL5A1, and ROR2. The association of OA-related mRNAs to HSPB1 was additionally confirmed in OA tissues by the quantitative RIP-PCR experiments. Further experiment demonstrated the downregulation of HSPB1 in OA tissues. In conclusion, our current study confirmed HSPB1 as an RNA-binding protein and revealed its potential function in the pathological process of OA, providing a reliable insight to further investigate the molecular regulation mechanism of HSPB1 in OA.

Association between traditional Chinese Medicine and osteoarthritis outcome: A 5-year matched cohort study

Objective

The aim of this study was to investigate the relationship between Traditional Chinese medicine (TCM) and pain reduction, hospital readmission, and joint replacement in patients with osteoarthritis (OA). Chinese herbal medicine (CHM) prescription patterns were further analyzed to confirm the association with prognosis and quality of life in OA patients.

Methods

We retrospectively followed 3,850 hospitalized patients with osteoarthritis between January 2018 and December 2022 using the hospital's HIS system. Propensity score matching (PSM) was used for data matching. Cox's proportional risk model was used to assess the impact of various factors on the outcomes of patients with OA, including pain worsening, readmission, and joint replacement. The Kaplan-Meier survival curve was applied to determine the impact of TCM intervention time on patient outcomes. Data mining methods including association rules, cluster analysis, and random walks have been used to assess the efficacy of TCM.

Results

The utilization rate of TCM in OA patients was 67.01% (2,511/3,747). After PSM matching, 1,228 TCM non-user patients and 1,228 TCM user patients were eventually included. The outcomes of pain worsening, re-admission rate, and joint replacement rate of the TCM non-user group were observably higher than those of the TCM user group with OA (p < 0.05). Based on the Cox proportional risk model, TCM is an independent protective factor. Compared with non-TCM users, TCM users had 58.4% lower rates of pain, 51.1% lower rates of re-admission, and 42% lower rates of joint replacement. In addition, patients in the high-exposure subgroup (TCM＞24 months) had a markedly lower risk of outcome events than those in the low-exposure subgroup (TCM ≤24 months). Data mining methods have shown that TCM therapy can significantly improve immune-inflammatory indices, VAS scores, and SF-36 scale scores in OA patients.

Conclusion

s TCM acts as a protective factor to improve the prognosis of patients with OA, and the benefits of long-term use of herbal medicines are even greater.

Effect of Traditional Chinese Non-Pharmacological Therapies on Knee Osteoarthritis: A Narrative Review of Clinical Application and Mechanism

Knee osteoarthritis (KOA) stands as a degenerative ailment with a substantial and escalating prevalence. The practice of traditional Chinese non-pharmacological therapy has become a prevalent complementary and adjunctive approach. A mounting body of evidence suggests its efficacy in addressing KOA. Recent investigations have delved into its underlying mechanism, yielding some headway. Consequently, this comprehensive analysis seeks to encapsulate the clinical application and molecular mechanism of traditional Chinese non-pharmacological therapy in KOA treatment. The review reveals that various therapies, such as acupuncture, electroacupuncture, warm needle acupuncture, tuina, and acupotomy, primarily target localized knee components like cartilage, subchondral bone, and synovium. Moreover, their impact extends to the central nervous system and intestinal flora. More perfect experimental design and more comprehensive research remain a promising avenue in the future.

[Stromal Cell-Derived Factor 1α Inhibits Chondrocyte Apoptosis and Promotes Autophagy Through the Akt Signaling Pathway]

Objective

To investigate the effects of stromal cell-derived factor 1α (SDF-1α) on the apoptosis and autophagy of chondrocytes and the underlying mechanisms.

Methods

Chondrocytes were isolated from the knee joints of neonatal mice. The chondrocytes were then stimulated with 0 (the control group), 50, 100, and 200 ng/mL of SDF-1α. CCK-8 assay was performed to determine the effects of SDF-1α stimulation for 24 h, 48 h, and 72 h on the viability of the chondrocytes. Wound healing assay was conducted to determine the effects of SDF-1α stimulation for 12 h and 24 h on chondrocyte migration. The changes in the expression of Akt signaling pathway proteins in chondrocytes were determined by Western blot assay. Chondrocytes were stimulated with 0 (the control group) and 200 ng/mL of SDF-1α. Flow cytometry was performed to determine the effect of SDF-1α on the apoptosis of chondrocytes. Transmission electron microscope was used to examine the effect of SDF-1α on chondrocyte autophagy. Immunofluorescence staining assays were performed to visualize the differences in p-Akt expression and distribution in chondrocytes treated with SDF-1α.

Results

Compared with the control group, findings for the experimental groups showed that SDF-1α at the concentrations of 50, 100, and 200 ng/mL did not decrease chondrocyte activity at any time point (P<0.01) and it consistently promoted chondrocyte migration at 24 h (P<0.05). Western blot results revealed that, in comparison to the control group, SDF-1α at concentrations of 50, 100, and 200 ng/mL significantly up-regulated the protein expression of p-Akt in chondrocytes, while no significant difference in Akt expression was observed. Flow cytometry demonstrated that SDF-1α could inhibit chondrocyte apoptosis (P<0.05) and transmission electron microscopic observation showed that SDF-1α promoted chondrocyte autophagy (P<0.05). Immunofluorescence staining showed that the expression of p-Akt in chondrocytes was concentrated in the perinuclear area of the cells and this expression was further enhanced in the perinuclear area of the chondrocytes after treatment with SDF-1α.

Conclusion

SDF-1α inhibits chondrocyte apoptosis and promotes chondrocyte migration and autophagy through activating the Akt signaling pathway.

Our biology working against us in obesity: A narrative review on implications for management of osteoarthritis

Obesity is the major modifiable risk factor for osteoarthritis (OA). A major focus of management in OA is weight loss. Although we live in an obesogenic environment, obesity has a predominantly genetic and epigenetic basis. This explains a person's weight set point which is defended by biological mechanisms making weight loss difficult to achieve and maintain long term, regardless of the methods used. Significant weight regain occurs after weight loss, with weight tending to return to pre-treatment levels after cessation of interventions including the glucagon-like peptide-1 (GLP-1) agonists. An area that has received little attention is the slow, insidious weight creep of 0.5-1 kg/year over adulthood that sees individuals relentlessly increase weight. There is evidence that low intensity, personalised lifestyle interventions can prevent this weight creep, providing patients with achievable goals. In this narrative review, we examine the evidence for weight loss in OA, the biological mechanisms that make weight loss difficult to achieve and maintain and the potential negative impacts on patients. We review the evidence for preventing weight gain, the improvement in patient outcomes and the potential for significant healthcare savings through reduced knee replacements. We propose a combined approach of weight loss when indicated, together with targeting weight creep across adult years and the potential role of metformin. Implementing these combined approaches is likely to be more effective in improving patient related outcomes, reducing joint damage and healthcare costs, than our current focus on achieving weight loss in OA.

Adapting a Clinical Practice Guideline for Management of Patients with Knee and Hip Osteoarthritis by Hong Kong Physiotherapists

Knee and hip osteoarthritis are common disabling conditions globally. Although numerous international clinical practice guidelines exist to guide physiotherapy management, not all recommendations issued from these guidelines can be translated to other contexts without considering the cultural acceptability and clinical implementability of targeted countries. Because the ADAPTE framework provides a robust methodology to adapt guidelines to the local context, this study used its methodology to adapt high-quality guideline recommendations to promote optimal physiotherapy care for knee and hip osteoarthritis in Hong Kong. The ADAPTE framework was used and modified to complete the adaptation process. International clinical practice guidelines were identified from eight guideline clearinghouses and six electronic databases. Two independent reviewers critically appraised the eligible guidelines using the AGREE II tool. We extracted and tabulated recommendations from high-quality guidelines. A voting-based consensus among interdisciplinary experts was conducted to decide on suitable recommendations for the Hong Kong context and whether there was a need to modify them. Pertinent recommendations were then translated into the traditional Chinese language. Our team members suggested modifying four tools and adding one to explore the patient's feedback on the recommendations, to the ADAPTE framework. The adaptation was performed on three high-quality guidelines. We adapted 28 and 20 recommendations for treating knee and hip osteoarthritis, respectively. We recommend a multimodal treatment for managing knee and hip osteoarthritis. Land- and aquatic-based exercises, patient education, and self-management were strongly recommended for patients with knee osteoarthritis. Land- and aquatic-based exercises were strongly recommended for patients with hip osteoarthritis. This is the first adaptation study in Hong Kong. It provides guidance to local physiotherapists on managing patients with knee and hip osteoarthritis. Future studies should test the effectiveness of implementing this adapted guideline to improve local physiotherapy care in Hong Kong.

Osteoarthritis of the hip: is radiography still needed?

Diagnosis of hip osteoarthritis (OA) is based on clinical arguments, and medical imaging is obtained to confirm the diagnosis and rule out other possible sources of pain. Conventional radiographs are recommended as the first line imaging modality to investigate chronic hip pain. They should be obtained in a rigorous technique that includes an antero-posterior (AP) radiograph of the pelvis. The choice of the appropriate lateral view depends on the clinical indication, Lequesne's false profile being valuable in the assessment of OA. Magnetic resonance imaging (MRI) is more sensitive to detect joint effusion/synovitis, cartilage, labral, and bone marrow lesions. However, structural joint changes are frequent in asymptomatic population and neither radiographs nor MRI have shown a good correlation with pain and functional impairment. MRI seems to be more suitable than radiographs as a biomarker for clinical trials addressing early OA. The absence of a validated MR biomarker of early OA, together with issues related to machine availability and MRI protocol repeatability, prevent the widespread use of MRI in clinical trials.

Longbie capsules reduce bone loss in the subchondral bone of rats with comorbid osteoporosis and osteoarthritis by regulating metabolite alterations

Background and objective

With the development of global population aging, comorbidity (≥2 diseases) is a common health problem among elderly people. Osteoarthritis (OA) and osteoporosis (OP) are common in elderly individuals. There is a lack of drug therapy for OA and OP comorbidities. The purpose of this study was to explore the efficacy and mechanism of Longbie capsule (LBJN), which contains various plant herbs, in treating OA and OP comorbidities (OA + OP) in rats using metabolomics techniques.

Methods

We created an OA + OP rat model through bilateral oophorectomy combined with meniscus instability surgery. Thirty SD rats were randomly divided into five groups (six in each group), namely, the sham group, OA group, OA + OP group, LBJN low-dose group (0.625 g/kg, OA + OP+LB-L group) and LBJN high-dose group (1.25 g/kg, OA + OP+LB-H group). After 8 weeks of intervention, we used micro-CT to detect bone microstructure status, ELISA to measure bone metabolism indicators, and UPLC-MS technology for metabolomics analysis. Finally, the screened differentially expressed metabolites were subjected to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and functional enrichment analysis.

Results

The micro-CT results showed that LBJN significantly improved the bone mineral density (BMD) and bone quality of subchondral bone in OA + OP rats, and LBJN regulated the expression of bone alkaline phosphatase (BALP), osteoprotegerin (OPG), and tartrate-resistant acid phosphatase (TRACP) in serum to maintain bone metabolism balance. Metabolomics analysis showed that the metabolic trajectory of OA + OP rats after intervention in the OA + OP+LB-H group showed significant changes, and 107 potential biomarkers could be identified. Among them, 50 metabolites were upregulated (such as zeranol) and 57 were downregulated (such as vanillactic acid). The KEGG functional enrichment results indicated that the differentially expressed metabolites are mainly involved in amino acid metabolism, lipid metabolism, and carbohydrate metabolism. The KEGG pathway enrichment results indicated that LBJN may exert therapeutic effects on OA + OP rats by regulating the cAMP signaling pathway, and the FoxO signaling pathway.

Conclusion

LBJN can maintain bone metabolism balance by regulating serum lipid metabolism, amino acid metabolism, carbohydrate metabolism, and estrogen, thereby reducing bone loss in subchondral bone, which may be a potential mechanism through which LBJN treats OA + OP.

IL-17 in osteoarthritis: A narrative review

Osteoarthritis (OA) is a painful joint disease that is common among the middle-aged and elderly populations, with an increasing prevalence. Therapeutic options for OA are limited, and the pathogenic mechanism of OA remains unclear. The roles of cytokines and signaling pathways in the development of OA is a current research hot spot. Interleukin (IL)-17 is a pleiotropic inflammatory cytokine produced mainly by T helper 17 cells that has established roles in host defense, tissue repair, lymphoid tissue metabolism, tumor progression, and pathological processes of immune diseases, and studies in recent years have identified an important role for IL-17 in the progression of OA. This narrative review focuses on the mechanisms by which IL-17 contributes to articular cartilage degeneration and synovial inflammation in OA and discusses how IL-17 and the IL-17 signaling pathway affect the pathological process of OA. Additionally, therapeutic targets that have been proposed in recent years based on IL-17 and its pathway in OA are summarized as well as recent advances in the study of IL-17 pathway inhibitors and the potential challenges of their use for OA treatment.

Recommendations for the management of hip and knee osteoarthritis: A systematic review of clinical practice guidelines

OBJECTIVES

Guideline adherence for hip and knee osteoarthritis management is often poor, possibly related to the quality and/or inconsistent recommendations. This systematic review of hip and knee osteoarthritis guidelines aimed to appraise the quality and consistency in recommendations across higher-quality guidelines.

METHODS

Eight databases, guideline repositories, and professional associations websites were searched on 27/10/2022. Guideline quality was appraised using the Appraisal of Guidelines for Research and Evaluation II (AGREE II tool) (six domains). Higher quality was defined as scoring ≥60% for domains 3 (rigour of development), 6 (editorial independence), plus one other. Consistency in recommendations across higher-quality guidelines was reported descriptively. This review was registered prospectively (CRD42021216154).

RESULTS

Seven higher-quality and 18 lesser-quality guidelines were included. AGREE II domain scores for higher-quality guidelines were > 60% except for applicability (average 46%). Higher-quality guidelines consistently recommended in favour of education, exercise, and weight management and non-steroidal anti-inflammatory drugs (hip and knee), and intra-articular corticosteroid injections (knee). Higher quality guidelines consistently recommended against hyaluronic acid (hip) and stem cell (hip and knee) injections. Other pharmacological recommendations in higher-quality guidelines (e.g., paracetamol, intra-articular corticosteroid (hip), hyaluronic acid (knee)) and adjunctive treatments (e.g., acupuncture) were less consistent. Arthroscopy was consistently recommended against in higher-quality guidelines. No higher-quality guidelines considered arthroplasty.

CONCLUSION

Higher-quality guidelines for hip and knee osteoarthritis consistently recommend clinicians implement exercise, education, and weight management, alongside consideration of Non-Steroidal Anti-Inflammatory Drugs and intra-articular corticosteroid injections (knee). Lack of consensus on some pharmacological options and adjunctive treatments creates challenges for guideline adherence. Future guidelines must prioritise providing implementation guidance, considering consistently low applicability scores.

The Impact of Arthroscopy on Surgical Decision-Making and Outcomes in Osteoarthritis Patients Undergoing Unicompartmental Knee Arthroplasty

Background and objective Although unicompartmental knee arthroplasty (UKA) is a minimally invasive procedure, its application is limited due to strict criteria related to indications. In clinical practice, the aid of procedures such as arthroscopy is occasionally required to determine the surgical indication and thereby improve prognosis. In light of this, this study aimed to evaluate the impact of intraoperative arthroscopy on surgical decision-making in osteoarthritis (OA) patients and the prognosis of patients undergoing UKA. Methodology The clinical records of patients diagnosed with knee OA who underwent knee arthroplasty between January 2017 and January 2020 were retrospectively analyzed. The inclusion criteria were as follows: patients with radiographic evidence of single-compartmental Kellgren-Lawrence (KL) grade 3 or 4 knee OA but presenting symptoms of persistent multicompartmental knee pain or locking for at least six months, with a history of anterior cruciate ligament (ACL) injury or meniscus tear. They had undergone either UKA or total knee arthroplasty (TKA). Data on clinical characteristics and outcomes at baseline and during follow-up were collected. Results A total of 429 patients were included in the study. Patients who underwent arthroscopy were more likely to undergo UKA surgery than those who did not (p<0.05). Among patients who underwent UKA, no instances of blood transfusion during hospitalization or postoperative complications were reported, regardless of whether arthroscopy was performed or not. Although the overall Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and Knee Society Functional Score (KSFS) did not differ between the two groups, the Knee Society Score (KSS) was significantly higher in patients who underwent arthroscopy (88.77 ±5.09) compared to those who did not (85.53 ±5.11). Similarly, the arthroscopy group had a higher overall Forgotten Joint Score (FJS) (44.6 ±4.20) than the UKA-only group (42.05 ±3.58). Conclusion Arthroscopy findings can assist in surgical decision-making for OA patients. Performing arthroscopy and UKA simultaneously is relatively safe and may be associated with favorable outcomes.

Specification, validation, and adherence of quality indicators to optimize the safe use of nonsteroidal anti-inflammatory drugs for knee osteoarthritis pain in the primary care setting

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) used for osteoarthritis (OA) in primary care may cause gastrointestinal or renal injury. This study estimated adherence to two quality indicators (QIs) to optimize NSAID safety: add proton pump inhibitors (PPI) to NSAIDs for patients with gastrointestinal (GI) risk (QI #1 NSAID-PPI) and avoid oral NSAIDs in chronic kidney disease (CKD) stage G4 or G5 (QI #2 NSAID-CKD).

METHODS

This retrospective study included index primary care clinic visits for knee OA at our health system in 2019. The validation cohort consisted of a random sample of 60 patients. The remainder were included in the expanded cohort. Analysis of structured data extracts was validated against chart review of clinic visit notes (validation cohort) and estimated QI adherence (expanded cohort).

RESULTS

Among 60 patients in the validation cohort, analysis of data extracts was validated against chart review for QI #1 NSAID-PPI (100% sensitivity and 91% specificity) and QI #2 NSAID-CKD (100% accuracy). Among 335 patients in the expanded cohort, 44% used NSAIDs, 27% used PPIs, 73% had elevated GI risk, and only 2% had CKD stage 4 or 5. Twenty-one percent used NSAIDs and had elevated GI risk but were not using PPIs. Therefore, adherence to QI #1 NSAID-PPI was 79% (95% CI, 74-83%). No patients with CKD stage 4 or 5 used NSAIDs. Therefore, adherence to QI #2 NSAID-CKD was 100%.

CONCLUSION

A substantial proportion of knee OA patients with GI risk factors did not receive PPI with NSAID therapy during primary care visits.

Regulating spleen and stomach can improve bone and joint function of knee osteoarthritis patients complicated with osteoporosis

OBJECTIVE

This study was designed to determine the influences of spleen and stomach conditioning treatment in Traditional Chinese Medicine (TCM) on patients with both knee osteoarthritis (KOA) and osteoporosis (OP).

METHODS

The medical records of 108 patients with both KOA and OP treated in Wuhan No. 1 Hospital between February 2020 and December 2021 were retrospectively studied. Among them, 58 patients treated with western medicine alone were assigned to a control group, and 50 patients who received spleen and stomach conditioning treatment in TCM based on western medicine treatment were assigned to an observation group. The efficacy on the two groups was compared. The joint function, pain, inflammatory factors and bone turnover markers in the two groups before and after treatment were analyzed, as well as the incidence of adverse reactions after treatment. The prognosis of the patients at 12 months after treatment was counted, and the influencing factors of poor prognosis were analyzed by multivariate analysis.

RESULTS

The observation group showed a notably higher total effective rate than the control group (P<0.05). After treatment, the observation group had notably higher Lysholm score, but notably lower Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and visual analogue scale (VAS) scores than the control group (all P<0.05). After treatment, the bone turnover markers (beta collagen degradation products (β-CTx) and procollagen type I amino-terminal propeptide (P1NP)) in both groups decreased notably (P<0.05), with notably lower levels of them in the observation group than those in the control group (both P<0.05). Additionally, after the treatment, the inflammatory indexes (interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)) in both groups decreased notably (all P<0.05), with notably lower levels of them in the observation group than those in the control group (all P<0.05). Moreover, the observation group presented a notably lower incidence of adverse reactions than the control group (P<0.05). The rate of poor prognosis in the observation group was notably lower than that in the control group. According to multiple logistic regression analysis, older age, higher BMI, higher Kellgren-Lawrence grading based on X-ray and history of bone fracture were independent risk factors for poor prognosis, and spleen and stomach conditioning treatment was an independent protective factor.

CONCLUSION

Additional TCM spleen and stomach conditioning treatment can substantially improve the efficacy in patients with both KOA and OP by adjusting the inflammatory factors and bone turnover markers of patients, improving their joint function, alleviating their pain, and strongly preventing adverse reactions, so it is of great clinical application value.

Identifying strategies that support equitable person-centred osteoarthritis care for diverse women: content analysis of guidelines

INTRODUCTION

Women are disproportionately impacted by osteoarthritis (OA) but less likely than men to access early diagnosis and management, or experience OA care tailored through person-centred approaches to their needs and preferences, particularly racialized women. One way to support clinicians in optimizing OA care is through clinical guidelines. We aimed to examine the content of OA guidelines for guidance on providing equitable, person-centred care to disadvantaged groups including women.

METHODS

We searched indexed databases and websites for English-language OA-relevant guidelines published in 2000 or later by non-profit organizations. We used manifest content analysis to extract data, and summary statistics and text to describe guideline characteristics, person-centred care (PCC) using a six-domain PCC framework, OA prevalence or barriers by intersectional factors, and strategies to improve equitable access to OA care.

RESULTS

We included 36 OA guidelines published from 2003 to 2021 in 8 regions or countries. Few (39%) development panels included patients. While most (81%) guidelines included at least one PCC domain, guidance was often brief or vague, few addressed exchange information, respond to emotions and manage uncertainty, and none referred to fostering a healing relationship. Few (39%) guidelines acknowledged or described greater prevalence of OA among particular groups; only 3 (8%) noted that socioeconomic status was a barrier to OA care, and only 2 (6%) offered guidance to clinicians on how to improve equitable access to OA care: assess acceptability, availability, accessibility, and affordability of self-management interventions; and employ risk assessment tools to identify patients without means to cope well at home after surgery.

CONCLUSIONS

This study revealed that OA guidelines do not support clinicians in caring for diverse persons with OA who face disadvantages due to intersectional factors that influence access to and quality of care. Developers could strengthen OA guidelines by incorporating guidance for PCC and for equity that could be drawn from existing frameworks and tools, and by including diverse persons with OA on guideline development panels. Future research is needed to identify multi-level (patient, clinician, system) strategies that could be implemented via guidelines or in other ways to improve equitable, person-centred OA care.

PATIENT OR PUBLIC CONTRIBUTION

This study was informed by a team of researchers, collaborators, and thirteen diverse women with lived experience, who contributed to planning, and data collection, analysis and interpretation by reviewing study materials and providing verbal (during meetings) and written (via email) feedback.

Structural and functional brain changes in people with knee osteoarthritis: a scoping review

Background

Knee osteoarthritis is a highly prevalent disease worldwide that leads to functional disability and chronic pain. It has been shown that not only changes are generated at the joint level in these individuals, but also neuroplastic changes are produced in different brain areas, especially in those areas related to pain perception, therefore, the objective of this research was to identify and compare the structural and functional brain changes in knee OA versus healthy subjects.

Methodology

Searches in MEDLINE (PubMed), EMBASE, WOS, CINAHL, SCOPUS, Health Source, and Epistemonikos databases were conducted to explore the available evidence on the structural and functional brain changes occurring in people with knee OA. Data were recorded on study characteristics, participant characteristics, and brain assessment techniques. The methodological quality of the studies was analysed with Newcastle Ottawa Scale.

Results

Sixteen studies met the inclusion criteria. A decrease volume of the gray matter in the insular region, parietal lobe, cingulate cortex, hippocampus, visual cortex, temporal lobe, prefrontal cortex, and basal ganglia was found in people with knee OA. However, the opposite occurred in the frontal lobe, nucleus accumbens, amygdala region and somatosensory cortex, where an increase in the gray matter volume was evidenced. Moreover, a decreased connectivity to the frontal lobe from the insula, cingulate cortex, parietal, and temporal areas, and an increase in connectivity from the insula to the prefrontal cortex, subcallosal area, and temporal lobe was shown.

Conclusion

All these findings are suggestive of neuroplastic changes affecting the pain matrix in people with knee OA.

Core Recommendations for Osteoarthritis Care: A Systematic Review of Clinical Practice Guidelines

OBJECTIVE

To evaluate the quality of clinical practice guidelines (CPGs) for interventions in management of osteoarthritis (OA) and to provide a synthesis of high-quality CPG recommendations.

METHODS

Five databases (OvidSP Medline, Cochrane, Cumulative Index to Nursing and Allied Health Literature [CINAHL], Embase, and the Physiotherapy Evidence Database [PEDro]) and 4 online guideline repositories were searched. CPGs for the management of OA were included if they were 1) written in English and published from January 2015 to February 2022, focused on adults age ≥18 years, and met the criteria of a CPG as defined by the Institute of Medicine; and 2) were rated as high quality on the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. CPGs for OA were excluded if they were available via institutional access only, only addressed recommendations for the system/organization of care and did not include interventional management recommendations, and/or included other arthritic conditions.

RESULTS

Of 20 eligible CPGs, 11 were appraised as high quality and included in the synthesis. Of interest were the hip, knee, hand, and glenohumeral joints and/or polyarticular OA. Consistent recommendations were that care should be patient centered and include exercise, education, and weight loss (where appropriate). Nonsteroidal antiinflammatory drugs and surgical interventions were recommended for disabling OA that had not improved with nonsurgical care. Hand orthoses should be recommended for patients with hand OA.

CONCLUSION

This synthesis of high-quality CPGs for OA management offers health care providers with clear, simple guidance of recommended OA care to improve patient outcomes.

Proximal fibular axis is a reliable landmark for tibial coronal alignment in patients with or without knee osteoarthritis: A radiological comparative study

BACKGROUND

Proper coronal alignment of the limb is of vital importance in the progression of knee osteoarthritis even in the long-term survivorship of component after total knee arthroplasty (TKA). Nevertheless, to the best of our knowledge, the relationship between coronal fibular axis and tibial mechanical axis had not reached a consensus in the literatures available. The current study aimed to explore the anatomic relationship between tibia and fibula alignment.

METHODS

A total of 100 patients with knee osteoarthritis scheduled for total knee arthroplasty were enrolled in this study (Group A), and radiographic measurement was compared to a control group of 100 healthy volunteers without knee osteoarthritis (Group B). Full-length standing hip-to-ankle radiographs were used to assess limb alignment. The angle between coronal proximal fibular anatomic axis and tibia mechanical axis (PFTA) was used to represent the anatomic relationship between tibia and fibula alignment. A negative value indicates fibula varus relative to tibia mechanical axis, while a positive value indicates fibula valgus.

RESULTS

The mean PFTAs were -0.9° ± 0.9° and -1.0° ± 0.8° in Groups A and B. There was no significant difference between the two groups. No significant difference was detected in PFTA distribution in the group A and B. When the mean value of PFTA is used as baseline data, the percentage of subjects in which the PFTA deviation was within 0.5°, 1°, and 1.5° was 51%, 84%, and 94% in Group A and 53%, 87%, and 96% in Group B. There was also no significant difference in distribution deviation between the two groups. No patient-specific factors were correlated with the PFTA.

CONCLUSIONS

The proximal fibular anatomic axis is a reliable landmark for tibial mechanical axis in the coronal plane in patients with or without knee osteoarthritis.

Efficacy and safety of combined Chinese and Western medicine in the treatment of knee osteoarthritis: a prospective, multicenter cohort study

Purpose: To conduct a real-world evaluation of the efficacy and safety of combined Chinese and Western medicine in treating knee osteoarthritis (KOA). Methods: A multicenter, prospective cohort study design was employed, enrolling 450 KOA patients (Kellgren-Lawrence score of 3 or less). The patients were divided into a Western medicine treatment group (WM group) and a combined Western and traditional Chinese medicine treatment group (WM-CM group). A 6-week treatment plan was administered, and follow-up visits occurred at 2 weeks, 4 weeks, and 6 weeks after initiating treatment. The primary outcome indicator was the total Western Ontario and McMaster Universities Arthritis Index (WOMAC) score after 6 weeks of treatment. Secondary outcome indicators included WOMAC subscales for pain, stiffness, and joint function, visual analogue scale (VAS) score, physical component summary (PCS), mental component summary (MCS), and clinical effectiveness. The incidence of drug-related adverse events was used as a safety evaluation indicator. Results: A total of 419 patients were included in the final analysis: 98 in the WM group and 321 in the WM-CM group. The baseline characteristics of the two groups were comparable, except for the incidence of stiffness symptoms and stiffness scores. After 6 weeks of treatment, the WM-CM group exhibited superior results to the WM group in improving the total WOMAC score (24.71 ± 1.38 vs. 16.36 ± 0.62, p < 0.001). The WM-CM group also outperformed the WM group in WOMAC pain and joint function scores, VAS score, PCS score, MCS score, and clinical effectiveness (p < 0.05), which was consistent with the findings of the main evaluation index. Subgroup analysis indicated that the combined Chinese and Western medicine treatment showed more pronounced benefits in patients under 65 years of age and in those with a Kellgren-Lawrence (K-L) classification of 0-I. Throughout the study, no adverse effects were observed in either group. Conclusion: The combination of Chinese and Western medicine demonstrated superiority over Western medicine alone in relieving knee pain symptoms, improving knee function, and enhancing the quality of life for KOA patients with a K-L score of 3 or less. Moreover, the treatment exhibited a good safety profile. Clinical Trial Registration: (https://www.chictr.org.cn/), identifier (ChiCTR1900027175).

Exosomes from osteoarthritic fibroblast-like synoviocytes promote cartilage ferroptosis and damage via delivering microRNA-19b-3p to target SLC7A11 in osteoarthritis

Objective

Our previous studies revealed that normal synovial exosomes promoted chondrogenesis, and microRNA (miR)-19b-3p independently related to osteoarthritis (OA) risk. Subsequently, this study intended to further explore the effect of OA fibroblast-like synoviocyte (OA-FLS) exosomal miR-19b-3p on OA ferroptosis and its potential mechanisms.

Methods

Interleukin (IL)-1β-stimulated chondrocytes and medial meniscus surgery were used to construct the OA cellular model and the OA rat model, respectively. OA-FLS exosomes with/without miR-19b-3p modification were added to the IL-1β-stimulated chondrocytes and OA rat models, followed by direct miR-19b-3p mimic/inhibitor transfection with/without SLC7A11 overexpression plasmids. miR-19b-3p, ferroptosis-related markers (malondialdehyde (MDA), glutathione (GSH)/oxidized glutathione (GSSG), ferrous ion (Fe2+), glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), and acyl-CoA synthetase long-chain family member 4 (ACSL4)), mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) levels were detected.

Results

Enhanced ferroptosis reflected by dysregulated ferroptosis-related markers, a reduced MMP, and an increased ROS was observed in cartilage tissues from OA patients vs. controls, IL-1β-stimulated chondrocytes vs. normal ones, and OA rat models vs. sham, so did miR-19b-3p. OA-FLS exosomes promoted MDA, Fe2+, ACSL4, and ROS but reduced cell viability, GSH/GSSG, GPX4, SLC7A11, and MMP in IL-1β-stimulated chondrocytes, whose effect was enhanced by miR-19b-3p mimics and attenuated by miR-19b-3p inhibitors. miR-19b-3p negatively regulated SLC7A11 and directly bound to SLC7A11 via luciferase reporter gene assay. Furthermore, SLC7A11 overexpression weakened miR-19b-3p mimics' effect on ferroptosis-related markers, MMP, or ROS in IL-1β-stimulated chondrocytes. OA-FLS exosomes also induced cartilage damage and ferroptosis in OA rats whose influence was tempered by miR-19b-3p inhibitors.

Conclusion

OA-FLS exosomal miR-19b-3p enhances cartilage ferroptosis and damage by sponging SLC7A11 in OA, indicating a potential linkage among synovium, cartilage, and ferroptosis during the OA process.

Quality indicators for osteoarthritis pain management in the primary care setting

BACKGROUND

Development of valid and feasible quality indicators (QIs) is needed to track quality initiatives for osteoarthritis pain management in primary care settings.

METHODS

Literature search identified published guidelines that were reviewed for QI extraction. A panel of 14 experts was assembled, including primary care physicians, rheumatologists, orthopedic surgeons, pain specialists, and outcomes research pharmacists. A screening survey excluded QIs that cannot be reliably extracted from the electronic health record or that are irrelevant for osteoarthritis in primary care settings. A validity screening survey used a 9-point Likert scale to rate the validity of each QI based on predefined criteria. During expert panel discussions, stakeholders revised QI wording, added new QIs, and voted to include or exclude each QI. A priority survey used a 9-point Likert scale to prioritize the included QIs.

RESULTS

Literature search identified 520 references published from January 2015 to March 2021 and 4 additional guidelines from professional/governmental websites. The study included 41 guidelines. Extraction of 741 recommendations yielded 115 candidate QIs. Feasibility screening excluded 28 QIs. Validity screening and expert panel discussion excluded 73 QIs and added 1 QI. The final set of 15 prioritized QIs focused on pain management safety, education, weight-management, psychological wellbeing, optimizing first-line medications, referral, and imaging.

CONCLUSION

This multi-disciplinary expert panel established consensus on QIs for osteoarthritis pain management in primary care settings by combining scientific evidence with expert opinion. The resulting list of 15 prioritized, valid, and feasible QIs can be used to track quality initiatives for osteoarthritis pain management.

Detrimental alteration of mesenchymal stem cells by an articular inflammatory microenvironment results in deterioration of osteoarthritis

BACKGROUND

Articular injection of mesenchymal stem cells (MSCs) has been applied to treat knee osteoarthritis (kOA), but its clinical outcomes are controversial. This study investigated whether an articular inflammatory microenvironment (AIM) impacts MSC-based therapy in a rat model of kOA.

METHODS

The biological change of MSCs and the functional change of MSCs on chondrocytes were evaluated under AIM. The key mediator and mechanism for the AIM impact on MSC therapy were explored via gain- and loss-of-function approaches.

RESULTS

The results showed that MSCs exerted potent anti-kOA effects in vivo and in vitro, but that this therapy become chondrodestructive if a chronic AIM was present. Mechanistically, the overexpression of MMP13 in the injected MSCs via a MAPKs-AP1 signaling axis was revealed as the underlying mechanism for the detriment outcome.

CONCLUSIONS

This study thus clarifies recent clinical findings while also suggesting a means to overcome any detrimental effects of MSC-based therapy while improving its efficacy.

Knowledge mapping of autophagy in osteoarthritis from 2004 to 2022: A bibliometric analysis

Background

Autophagy in osteoarthritis (OA) has become an active area of research with substantial value and potential. Nevertheless, few bibliometric studies have systematically analyzed the available research in the field. The main goal of this study was to map the available literature on the role of autophagy in OA and identify global research hotspots and trends.

Methods

The Web of Science Core Collection and Scopus databases were interrogated for studies of autophagy in OA published between 2004 and 2022. Microsoft Excel, VOSviewer and CiteSpace software were used to analyze and visualize the number of publications and associated citations, and reveal global research hotspots and trends in the autophagy in OA field.

Results

732 outputs published by 329 institutions from 55 countries/regions were included in this study. From 2004 to 2022, the number of publications increased. China produced the most publications (n=456), prior to the USA (n=115), South Korea (n=33), and Japan (n=27). Scripps Research Institute (n=26) was the most productive institution. Martin Lotz (n=30) was the highest output author, while Caramés B (n=302) was the highest output author. Osteoarthritis and Cartilage was the most prolific and most co-cited journal. Currently, the autophagy in OA research hotspots include chondrocyte, transforming growth factor beta 1 (TGF-β1), inflammatory response, stress, and mitophagy. The emerging research trends in this field are AMPK, macrophage, senescence, apoptosis, tougu xiaotong capsule (TXC), green tea extract, rapamycin, and dexamethasone. Novel drugs targeting specific molecule such as TGF-β and AMPK have shown therapeutic potential but are still in the preclinical stage of development.

Conclusions

Research on the role of autophagy in OA is flourishing. Martin Lotz, Beatriz Caramés, and Osteoarthritis and Cartilage have made outstanding contributions to the field. Prior studies of OA autophagy mainly focused on mechanisms underlying OA and autophagy, including AMPK, macrophages, TGF-β1, inflammatory response, stress, and mitophagy. Emerging research trends, however, are centered around the relationship between autophagy, apoptosis, and senescence, as well as drug candidates such as TXC and green tea extract. The development of new targeted drugs that enhance or restore autophagic activity is a promising strategy for the treatment of OA.

Association between weight gain and knee osteoarthritis: a systematic review

OBJECTIVE

Although weight loss is recommended to manage knee osteoarthritis (KOA), adults tend to gain weight with age which may affect KOA symptoms and progression. We conducted a systematic review and data synthesis to investigate the association between weight gain and KOA, defined by clinical features, structural progression, and total knee replacement (TKR).

DESIGN

MEDLINE and EMBASE were systematically searched for controlled trials and cohort studies of participants with (or at risk of) KOA examining the relationship between weight gain and KOA clinical features (pain, function, quality of life), structural progression, and TKR. Risk of bias was assessed using the ROBINS-I tool. Results were organised by outcome, with meta-analyses performed where appropriate.

RESULTS

Twenty-three studies were included. Results showed significant detrimental effects of weight gain on pain (4 of 7 studies), stiffness (2 of 2 studies), function (5 of 6 studies), and the single studies examining quality of life, and clinical and radiographic KOA. Weight gain adversely affected cartilage (6 of 9 studies), bone marrow lesions (1 of 4 studies), meniscal damage (1 of 3 studies) and effusion/synovitis (1 of 1 study). Weight gain significantly increased TKR (3 of 6 studies): meta-analysis of 2 with available data demonstrated significant increases in TKR/5 kg weight gain in women, HR 1.34 (95% CI 1.18-1.51), and in men, HR 1.25 (95% CI 1.16-1.34).

CONCLUSIONS

Weight gain in adults is associated with increased clinical and structural KOA and TKR. Prevention of weight gain should be considered to improve outcomes in KOA.

Characterizations of the Gut Bacteriome, Mycobiome, and Virome in Patients with Osteoarthritis

The gut microbiota plays an essential role in the regulation of the immune system and the etiology of human autoimmune diseases. However, a holistic understanding of the gut bacteriome, mycobiome, and virome in patients with osteoarthritis (OA) remains lacking. Here, we explored the gut microbiotas of 44 OA patients and 46 healthy volunteers via deep whole-metagenome shotgun sequencing of their fecal samples. The gut bacteriome and mycobiome were analyzed using a reference-based strategy. Gut viruses were identified from the metagenomic assembled contigs, and the gut virome was profiled based on 6,567 nonredundant viral operational taxonomic units (vOTUs). We revealed that the gut microbiome (including bacteriome, mycobiome, and virome) of OA patients is fundamentally altered, characterized by a panel of 279 differentially abundant bacterial species, 10 fungal species, and 627 vOTUs. The representative OA-enriched bacteria included Anaerostipes hadrus (GENOME147149), Prevotella sp900313215 (GENOME08259), Eubacterium_E hallii (GENOME000299), and Blautia A (GENOME001004), while Bacteroides plebeius A (GENOME239725), Roseburia inulinivorans (GENOME 001770), Dialister sp900343095 (GENOME075103), Phascolarctobacterium faecium (GENOME233517), and several members of Faecalibacterium and Prevotella were depleted in OA patients. Fungi such as Debaryomyces fabryi (GenBank accession no. GCA_003708665), Candida parapsilosis (GCA_000182765), and Apophysomyces trapeziformis (GCA_000696975) were enriched in the OA gut microbiota, and Malassezia restricta (GCA_003290485), Aspergillus fumigatus (GCA_003069565), and Mucor circinelloides (GCA_010203745) were depleted. The OA-depleted viruses spanned Siphoviridae (95 vOTUs), Myoviridae (70 vOTUs), and Microviridae (5 vOTUs), while 30 Siphoviridae vOTUs were enriched in OA patients. Functional analysis of the gut bacteriome and virome also uncovered their functional signatures in relation to OA. Moreover, we demonstrated that the OA-associated gut bacterial and viral signatures are tightly interconnected, suggesting that they may impact disease together. Finally, we showed that the multikingdom signatures are effective in discriminating the OA patients from healthy controls, suggesting the potential of gut microbiota for the prediction of OA and related diseases. Our results delineated the fecal bacteriome, mycobiome, and virome landscapes of the OA microbiota and provided biomarkers that will aid in future mechanistic and clinical intervention studies. IMPORTANCE The gut microbiome of OA patients was completely altered compared to that in healthy individuals, including 279 differentially abundant bacterial species, 10 fungal species and 627 viral operational taxonomic units (vOTUs). Functional analysis of the gut bacteriome and virome also revealed their functional signatures in relation to OA. We found that OA-associated gut bacterial and viral signatures were tightly interconnected, indicating that they may affect the disease together. The OA patients can be discriminated effectively from healthy controls using the multikingdom signatures, suggesting the potential of gut microbiota for the prediction of OA and related diseases.

Identification and validation of hub genes and potential drugs involved in osteoarthritis through bioinformatics analysis

Purpose: Osteoarthritis (OA) is a common degenerative disease, which still lacks specific therapeutic drugs. Synovitis is one of the most important pathological process in OA. Therefore, we aim to identify and analyze the hub genes and their related networks of OA synovium with bioinformatics tools to provide theoretical basis for potential drugs. Materials and methods: Two datasets were obtained from GEO. DEGs and hub genes of OA synovial tissue were screened through Gene Ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment as well as protein-protein interaction (PPI) network analysis. Subsequently, the correlation between expression of hub genes and ferroptosis or pyroptosis was analyzed. CeRNA regulatory network was constructed after predicting the upstream miRNAs and lncRNAs. The validation of hub genes was undertook through RT-qPCR and ELISA. Finally, potential drugs targeting pathways and hub genes were identified, followed by the validation of the effect of two potential drugs on OA. Results: A total of 161 commom DEGs were obtained, of which 8 genes were finally identified as hub genes through GO and KEGG enrichment analysis as well as PPI network analysis. Eight genes related to ferroptosis and pyroptosis respectively were significantly correlated to the expression of hub genes. 24 miRNAs and 69 lncRNAs were identified to construct the ceRNA regulatory network. The validation of EGR1, JUN, MYC, FOSL1, and FOSL2 met the trend of bioinformatics analysis. Etanercept and Iguratimod reduced the secretion of MMP-13 and ADAMTS5 of fibroblast-like synoviocyte. Conclusion: EGR1, JUN, MYC, FOSL1, and FOSL2 were identified as hub genes in the development of OA after series of bioinformatics analysis and validation. Etanercept and Iguratimod seemed to have opportunities to be novel drugs for OA.

Correlation between the Signal Intensity Alteration of Infrapatellar Fat Pad and Knee Osteoarthritis: A Retrospective, Cross-Sectional Study

Infrapatellar fat pad (IPFP) inflammation is a common pathological manifestation in knee osteoarthritis (OA). However, the significance of IPFP signal intensity alteration for clinical diagnosis and treatment of knee OA needs further research. We assessed IPFP signal intensity alteration (0-3), IPFP maximum cross-sectional area (CSA) and IPFP depth, meniscus injury, bone marrow edema, and cartilage injury from magnetic-resonance imaging (MRI) in 41 non-KOA patients (K-L grade 0 and grade I) and 68 KOA patients (K-L grade 2,3 and 4). We found that IPFP signaling was altered in all patients with KOA whose alteration was closely related to the K-L grading. We found that the IPFP signal intensity was increased in most OA patients, especially the ones in the late stage. There were significant differences in IPFP maximum CSA and IPFP depth between groups in KOA and non-KOA patients. Moreover, Spearman correlation analysis showed that IPFP signal intensity was moderately positively correlated with age, meniscal injury, cartilage injury, and bone marrow edema, and negatively correlated with height, while not correlated with visual analogue scale (VAS) scoring and body mass index (BMI). In addition, women have higher IPFP inflammation scores on MRI than men. In conclusion, IPFP signal intensity alteration is associated with joint damage in knee OA, which may have clinical significance for diagnosing and treating KOA.

Potential effects of teriparatide (PTH (1-34)) on osteoarthritis: a systematic review

Osteoarthritis (OA) is a common and prevalent degenerative joint disease characterized by degradation of the articular cartilage. However, none of disease-modifying OA drugs is approved currently. Teriparatide (PTH (1-34)) might stimulate chondrocyte proliferation and cartilage regeneration via some uncertain mechanisms. Relevant therapies of PTH (1-34) on OA with such effects have recently gained increasing interest, but have not become widespread practice. Thus, we launch this systematic review (SR) to update the latest evidence accordingly. A comprehensive literature search was conducted in PubMed, Web of Science, MEDLINE, the Cochrane Library, and Embase from their inception to February 2022. Studies investigating the effects of the PTH (1-34) on OA were obtained. The quality assessment and descriptive summary were made of all included studies. Overall, 307 records were identified, and 33 studies were included. In vivo studies (n = 22) concluded that PTH (1-34) slowed progression of OA by alleviating cartilage degeneration and aberrant remodeling of subchondral bone (SCB). Moreover, PTH (1-34) exhibited repair of cartilage and SCB, analgesic, and anti-inflammatory effects. In vitro studies (n = 11) concluded that PTH (1-34) was important for chondrocytes via increasing the proliferation and matrix synthesis but preventing apoptosis or hypertrophy. All included studies were assessed with low or unclear risk of bias in methodological quality. The SR demonstrated that PTH (1-34) could alleviate the progression of OA. Moreover, PTH (1-34) had beneficial effects on osteoporotic OA (OPOA) models, which might be a therapeutic option for OA and OPOA treatment.

Microstructural changes of cartilage and subchondral bone in a guinea pig model of early- and middle-stage patellofemoral arthritis

OBJECTIVE

Patellofemoral arthritis is a common type of knee osteoarthritis and a prime cause of anterior knee pain and disability. Most of the existing research on knee osteoarthritis focuses on tibial-femoral arthritis, while studies on patellofemoral arthritis are relatively rare. This study aims to observe changes in osteochondral and subchondral bone structure over time in the patella and femoral trochlea in an animal model of spontaneous patellofemoral arthritis.

METHODS

A total of 24 1-, 3- or 5-month-old healthy female Hartley guinea pigs were used for experiments. No intervention was applied, and the mechanical pain threshold was assessed prior to euthanasia. Bilateral knee joints were collected in the animals at the different ages, and the patellofemoral joints were taken to evaluate the bone microstructure of patellofemoral articular cartilage and subchondral bone by macroscopy, histopathology and micro-computed tomography (micro-CT).

RESULTS

There was a significant difference in the severity of femoral trochlea injury assessed by the Macro score between 5- and 1-month-old groups (P<0.01), as well as in patellar cartilage damage (P<0.05). The mechanical pain threshold of lower extremities in each group was statistically different between different age groups (P<0.05). The OARSI articular cartilage histopathological scores, including patella and femoral trochlea, were significantly different among 1-, 3- and 5-month-old groups. The 5-month-old group exhibited statistically lower values of bone volume/trabecular volume, trabecular number and trabecular thickness in the femoral subchondral bone and evidently higher structure model index than the 1-month-old group.

CONCLUSIONS

This study demonstrated that 3- to 5-month-old female Hartley guinea pigs can develop early-to-mid-stage spontaneous patellofemoral arthritis that causes significant cartilage degeneration and loss of subchondral bone. In addition, the bone microarchitecture of the femur is more severely degraded.

Nomogram model based on radiomics signatures and age to assist in the diagnosis of knee osteoarthritis

BACKGROUND

Knee osteoarthritis (KOA) is a common disease in the elderly. An effective method for accurate diagnosis could affect the management and prognosis of patients.

OBJECTIVES

To develop a nomogram model based on X-ray imaging data and age, and to evaluate its effectiveness in the diagnosis of KOA.

METHODS

A total of 4403 knee X-rays from 1174 patients (July 2017 to November 2018) were retrospectively analyzed. Radiomics features were extracted and selected from the X-ray image data to quantify the phenotypic characteristics of the lesion region. Feature selection was performed in three steps to enable the derivation of robust and effective radiomics signatures. Then, logistic regression (LR), support vector machine (SVM) AdaBoost, gradient boosting decision tree (GBDT), and multi-layer perceptron (MLP) was adopted to verify the performance of radiomics signatures. In addition, a nomogram model combining age with radiomics signatures was constructed. At last, receiver operating characteristic (ROC) curve, calibration and decision curves were used to evaluate the discriminative performance.

RESULTS

The LR model has the best classification performance among the four radiomics models in testing cohort (LR AUC vs. SVM AUC: 0.843 vs. 0.818, DeLong test P = 0.0024; LR AUC vs. GBDT AUC: 0.843 vs. 0.821, P = 0.0028; LR AUC vs. MLP AUC: 0.843 vs. 0.822, P = 0.0019). The nomogram model achieved better predictive efficacy than the radiomics model in testing cohort compared to radiomics models although the statistical difference was not significant (Nomogram AUC vs. Radiomics AUC: 0.847 vs. 0.843, P = 0.06). The decision curve analysis revealed that the constructed nomogram had clinical usefulness.

CONCLUSION

The nomogram model combining radiomics signatures with age has good performance for the accurate diagnosis of KOA and may help to improve clinical decision-making.

Effect of autologous platelet-rich plasma combined with sodium hyaluronate on clinical efficacy and serum inflammatory factors in patients with knee osteoarthritis

OBJECTIVE

To observe the effect of autologous platelet-rich plasma combined with sodium hyaluronate on clinical efficacy and serum inflammatory factor levels in patients with knee osteoarthritis.

METHODS

A retrospective study was conducted on a total of 99 knee osteoarthritis patients who underwent arthroscopic surgery after failed conservative treatment in No. 215 Hospital of Shaanxi Nuclear Industry from January 2019 to January 2022. Among them, 45 patients treated with only sodium hyaluronate injection after arthroscopic debridement were grouped as the control group (CG), and 54 patients treated with platelet-rich plasma combined with intra-articular injection of sodium hyaluronate after arthroscopic debridement were the observation group (OG). Visual analogue scale/score (VAS) and Lysholm knee scale (LKS) were used to evaluate the clinical therapeutic effect before and 5 weeks after treatment, and ELISA was to detect the changes of matrix metalloproteinase-3 (MMP-3), interleukin-1β (IL-1β), high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor-α (TNF-α) levels in the serum of patients before and 5 weeks after treatment. Risk factors affecting patient outcomes were analyzed by logistic regression.

RESULTS

Compared to theCG, the improvement of clinical efficacy in the OG was higher (P < 0.05), as well as its LKS score, while the VAS score after treatment in OG was markedly lower (P < 0.05). After treatment, MMP-3, IL-1β, hs-CRP, and TNF-α in the OG were significantly lower than those in the CG (P < 0.05). There was nodifference in the incidence rate of adverse reactions between the two groups (P > 0.05). Logistic regression analysis showed that younger age and lower BMI were protective factors for efficacy in the patients, while higher LKS and TNF-α were risk factors affecting the efficacy in the patients.

CONCLUSION

Intra-articular injection of platelet-rich plasma combined with sodium hyaluronate in the treatment of knee osteoarthritis can significantly reduce the symptoms of knee joint pain, improving knee joint function and in vivo inflammatory response.

Automatic assessment of knee osteoarthritis severity in portable devices based on deep learning

BACKGROUND

For knee osteoarthritis, the commonly used radiology severity criteria Kellgren-Lawrence lead to variability among surgeons. Most existing diagnosis models require preprocessed radiographs and specific equipment.

METHODS

All enrolled patients diagnosed with KOA who met the criteria were obtained from **** Hospital. This study included 2579 images shot from posterior-anterior X-rays of 2,378 patients. We used RefineDet to train and validate this deep learning-based diagnostic model. After developing the model, 823 images of 697 patients were enrolled as the test set. The whole test set was assessed by up to 5 surgeons and this diagnostic model. To evaluate the model's performance we compared the results of the model with the KOA severity diagnoses of surgeons based on K-L scales.

RESULTS

Compared to the diagnoses of surgeons, the model achieved an overall accuracy of 0.977. Its sensitivity (recall) for K-L 0 to 4 was 1.0, 0.972, 0.979, 0.983 and 0.989, respectively; for these diagnoses, the specificity of this model was 0.992, 0.997, 0.994, 0.991 and 0.995. The precision and F1-score were 0.5 and 0.667 for K-L 0, 0.914 and 0.930 for K-L 1, 0.978 and 0.971 for K-L 2, 0.981 and 0.974 for K-L 3, and 0.988 and 0.985 for K-L 4, respectively. All K-L scales perform AUC > 0.90. The quadratic weighted Kappa coefficient between the diagnostic model and surgeons was 0.815 (P < 0.01, 95% CI 0.727-0.903). The performance of the model is comparable to the clinical diagnosis of KOA. This model improved the efficiency and avoided cumbersome image preprocessing.

CONCLUSION

The deep learning-based diagnostic model can be used to assess the severity of KOA in portable devices according to the Kellgren-Lawrence scale. On the premise of improving diagnostic efficiency, the results are highly reliable and reproducible.

An Insight on the Biomedical Potential of Portuguese Propolis from Gerês

Osteoarthritis (OA), a progressive degenerative disease of weight-bearing joints, is the second leading cause of disability in the world. Despite all the advances and research over the last years, none of the proposed strategies has been effective in generating functional and long-lasting tissue. Due to the high prevalence of OA and the urgent need for an effective and successful treatment, interest in natural products as anti-inflammatory agents, such as propolis and its components, has emerged. In this work, we estimate the biomedical potential of Portuguese propolis, evaluating the in vitro antioxidant and anti-inflammatory effects of single hydroalcoholic extracts prepared with propolis from Gerês sampled over a five-year period (2011-2015) (G.EE70 and G.EE35). The in vivo and in vitro anti-inflammatory potential of the hydroalcoholic extract of mixtures of the same samples (mG.EE70 and mG.EE35) was evaluated for the first time too. DPPH• radical scavenging and superoxide anion scavenging assays showed the strong antioxidant potential of both hydroalcoholic extracts, either prepared from single propolis samples or from the mixtures of the same samples. Results also revealed an anti-inflammatory effect of mG.EE35, both in vitro by inhibiting BSA denaturation and in vivo in the OA-induced model by improving mechanical hyperalgesia as well as the gait pattern parameters. Results further support the use of propolis blends as a better and more efficient approach to take full advantage of the bioactive potential of propolis.

Physical therapy as a promising treatment for osteoarthritis: A narrative review

Osteoarthritis (OA) is the most prevalent joint disease and a leading cause of disability in older adults. With an increasing population ageing and obesity, OA is becoming even more prevalent than it was in previous decades. Evidence indicates that OA is caused by the breakdown of joint tissues from mechanical loading and inflammation, but the deeper underlying mechanism of OA pathogenesis remains unclear, hindering efforts to prevent and treat this disease. Pharmacological treatments are mostly related to relieving symptoms, and there is no drug for radical cure. However, compelling evidence suggests that regular practice of resistance exercise may prevent and control the development of several musculoskeletal chronic diseases including OA, which may result in improved quality of life of the patients. In this review, we introduced the current understanding of the mechanism and clinical treatments of OA pathogenesis. We also reviewed the recent study of physical therapy in the treatment of skeletal system disorders, especially in OA. Finally, we discuss the present challenges and promising advantages of physical therapy in OA treatment.

Non-invasive brain stimulation for osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease, the prevalence of OA is increasing, and the elderly are the most common in patients with OA. OA has a severe impact on the daily life of patients, this increases the demand for treatment of OA. In recent years, the application of non-invasive brain stimulation (NIBS) has attracted extensive attention. It has been confirmed that NIBS plays an important role in regulating cortical excitability and oscillatory rhythm in specific brain regions. In this review, we summarized the therapeutic effects and mechanisms of different NIBS techniques in OA, clarified the potential of NIBS as a treatment choice for OA, and provided prospects for further research in the future.

Emerging injectable therapies for osteoarthritis

Osteoarthritis (OA) affects more than 240 million people worldwide. In 2016, the Osteoarthritis Research Society International submitted a report to the United States Food and Drug Administration highlighting OA as a 'serious' disease, and appealed for the urgent development and review of new therapies to address a significant unmet need. Despite this, international guidelines for the treatment of OA have been largely unchanged for over a decade. There is now an updated understanding that OA is more than simply a non-inflammatory 'wear-and-tear' process involving articular cartilage. Based on this, potential emerging therapies are being developed that target novel inflammatory, pain, and regeneration pathways. Drugs targeting the latter are being lauded as 'Disease-Modifying Osteoarthritis Drugs' - a concept which has so far proved elusive in OA research. While this review does not recommend a change in current practice, it should prompt readers to rethink the OA treatment paradigm. The global pandemic has added another layer of consideration when managing patients with OA. At a time when there is more strain on hospital systems, there is a need to expand our pharmacological armamentarium in order to manage OA without elective surgery and hospital admission.

Identification and verification of ferroptosis-related genes in the synovial tissue of osteoarthritis using bioinformatics analysis

Background: Osteoarthritis (OA) is a major factor causing pain and disability. Studies performed to date have suggested that synovitis is possibly a critical OA-related pathological change. Ferroptosis represents a novel type of lipid peroxidation-induced iron-dependent cell death. However, its effect on OA remains largely unclear.

Objective: This work focused on identifying and validating the possible ferroptosis-related genes (FRGs) involved in synovitis of OA through bioinformatics analysis.

Materials and Methods: The microarray dataset GSE55235 was downloaded in the database Gene Expression Omnibus (GEO). By the Venn diagram and GEO2R, differentially expressed genes (DEGs) and ferroptosis DEGs (FDEGs) were detected. DEGs were screened by GO and KEGG enrichment analysis, as well as protein-protein interaction (PPI) analysis. Besides, the software Cytoscape and database STRING were utilized to construct hub gene networks. Moreover, this study used the database NetworkAnalyst to predict the target miRNAs of the hub genes. Finally, the hub genes were confirmed by analysis of the receiver operating characteristic (ROC) curve on the GSE12021 and GSE1919 databases. Considering the relationship between ferroptosis and immunity, this study applied CIBERSORTx to analyze the immune infiltration in OA in addition.

Results: This work discovered seven genes, including ATF3, IL6, CDKN1A, IL1B, EGR1, JUN, and CD44, as the hub FDEGs. The ROC analysis demonstrated that almost all hub genes had good diagnostic properties in GSE12021 and GSE 1919.

Conclusion: This study discovered seven FDEGs to be the possible diagnostic biomarkers and therapeutic targets of synovitis during OA, which sheds more light on the pathogenesis of OA at the transcriptome level.

OPN inhibits autophagy through CD44, integrin and the MAPK pathway in osteoarthritic chondrocytes

Background

To investigate whether osteopontin (OPN) affects autophagy in human osteoarthritic chondrocytes and determine the roles of CD44, αvβ3 integrin and the Mitogen-activated protein kinase (MAPK) pathway in this progress.

Methods

First, we compared the autophagy levels in the human osteoarthritis (OA) and normal cartilage, then, we cultured human OA chondrocytes in vitro and treated cells with recombinant human OPN (rhOPN) to determine autophagy changes. Next, the anti-CD44 and anti-CD51/61 monoclonal antibodies (Abs) or isotype IgG were used to determine the possible role of CD44 and αvβ3 integrin; subsequently, an inhibitor of the ERK MAPK pathway was used to investigate the role of ERK MAPK. Western blotting was used to measure the Beclin1, LC3 II and MAPK proteins expressions, mRFP-GFP-LC3 confocal imaging and transmission electron microscopy were also used to detect the autophagy levels. Cell Counting Kit-8 (CCK-8) was used to assay the proliferation and activity of chondrocytes.

Results

The LC3 protein was greatly decreased in OA cartilage compared to normal cartilage, and OPN suppressed the autophagy activity in chondrocytes in vitro. Blocking experiments with anti-CD44 and anti-CD51/61 Abs indicated that OPN could suppress the expression of LC3II and Beclin1 through αvβ3 integrin and CD44. Our results also indicated that the ratio of p-ERK/ERK but not p-P38/P38 and p-JNK/JNK was increased after the rhOPN treatment. The ERK inhibitor inhibited the activity of OPN in the suppression of autophagy, and the CCK-8 results showed that rhOPN could promote chondrocyte proliferation.

Conclusion

OPN inhibited chondrocyte autophagy through CD44 and αvβ3 integrin receptors and via the ERK MAPK signaling pathway.

Multimodal Magnetic Resonance Imaging to Diagnose Knee Osteoarthritis under Artificial Intelligence

This work aimed to investigate the application value of the multimodal magnetic resonance imaging (MRI) algorithm based on the low-rank decomposition denoising (LRDD) in the diagnosis of knee osteoarthritis (KOA), so as to offer a better examination method in the clinic. Seventy-eight patients with KOA were selected as the research objects, and they all underwent T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), fat suppression T2WI (SE-T2WI), and fat saturation T2WI (FS-T2WI). All obtained images were processed by using the I-LRDD algorithm. According to the degree of articular cartilage lesions under arthroscopy, the patients were divided into a group I, a group II, a group III, and a group IV. The sensitivity, specificity, accuracy, and consistency of KOA diagnosis of T1WI, T2WI, SE-T2WI, and FS-T2WI were analyzed by referring to the results of arthroscopy. The results showed that the peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM) of the I-LRDD algorithm used in this work were higher than those of image block priori denoising (IBPD) and LRDD, and the time consumption was lower than that of IBDP and LRDD (p < 0.05). The sensitivity, specificity, accuracy, and consistency (Kappa value) of multimodal MRI in the diagnosis of KOA were 88.61%, 85.3%, 87.37%, and 0.73%, respectively, which were higher than those of T1WI, T2WI, SE-T2WI, and FS-T2WI. The sensitivity, specificity, accuracy, and consistency of multimodal MRI in diagnosing lesions in group IV were 95%, 96.10%, 95.88%, and 0.70%, respectively, which were much higher than those in groups I, II, and III (p < 0.05). In conclusion, the LRDD algorithm shows a good image processing efficacy, and the multimodal MRI showed a good diagnosis effect on KOA, which was worthy of promotion clinically.

L-Glutamine alleviates osteoarthritis by regulating lncRNA-NKILA expression through the TGF-β1/SMAD2/3 signalling pathway

Osteoarthritis (OA) is a heterogeneous condition characterized by cartilage degradation, subchondral sclerosis, and osteophyte formation, and accompanied by the generation of pro-inflammatory mediators and degradation of extracellular matrix. The current treatment for early OA is focused on the relief of symptoms, such as pain, but this treatment cannot delay the pathological process. L-Glutamine (L-Gln), which has anti-inflammatory and anti-apoptotic effects, is the most abundant amino acid in human blood. However, its role in OA has not been systematically studied. Therefore, the objective of this work was to explore the therapeutic effect and molecular mechanism of L-Gln on OA. In vitro, we found that L-Gln could up-regulate the expression of the long non-coding RNA NKILA, which is regulated by the transforming growth factor-β1/SMAD2/3 pathway, and inhibit the activity of nuclear factor-κB, thereby decreasing the expression of nitric oxide synthase, cyclooxygenase-2, and matrix metalloproteinase-13 (MMP-13). This led to a reduction in the generation of nitrous oxide, prostaglandin E-2, tumour necrosis factor-α, and degradation of the extracellular matrix (i.e. aggrecan and collagen II) in rat OA chondrocytes. Moreover, intragastric administration of L-Gln reduced the degradation of cartilage tissue and expression of MMP-13 in a rat OA model. L-Gln also relieved the clinical symptoms in some patients with early knee joint OA. These findings highlight that L-Gln is a potential therapeutic drug to delay the occurrence and development of OA.

Influence of nerve block combined with general anesthesia on cognitive function and postoperative pain in patients undergoing knee joint replacement

OBJECTIVE

To investigate the influence of nerve block combined with general anesthesia on the cognitive function and postoperative pain of patients undergoing knee joint replacement and analyze the risk factors of postoperative cognitive dysfunction.

METHODS

A retrospective analysis was conducted on 104 elderly patients undergoing knee joint replacement in our hospital between January 2018 and January 2021. The control group (n=50) received laryngeal mask anesthesia, while the observation group (n=54) received ultrasound-guided nerve block combined with laryngeal mask anesthesia. The visual analogue scale (VAS) was adopted for scoring the pain intensity of both groups, and the Mini-Mental State Examination (MMSE) was used for evaluating changes in cognitive function before and after operation. The self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were adopted for scoring patientsbefore and after operation. Additionally, the time to spontaneous breathing recovery, time to wake up, time to open eyes when ordered, and extubation time of the two groups were recorded. The changes in serum IL-6, cortisol (Cor), and IL-10 before and after operation were compared. The two groups were compared in the dosage of used analgesic drugs, the first getting out-of-bed time, treatment expense, and hospitalization time. The correlation between VAS score and IL-6, Cor and IL-10 before and after treatment was analyzed. The adverse reactions of the two groups were also compared. Logistic regression was used to analyze risk factors for cognitive dysfunction.

RESULTS

After operation, the observation group experienced shorter spontaneous breathing recovery time, time to wake up, time to open eyes when ordered, and extubation time, than the control group (P<0.05). The observation group also consumed less sufentanil than the control group (P<0.05). Additionally, the observation group had lower VAS and MMSE scores than the control group at 6 and 12 h after operation (P>0.05) and lower SAS and SDS scores than the control group (P<0.05). Moreover, at 6 h after operation, the control group showed higher levels of IL-6, Cor and IL-10 than the observation group (P<0.05), and the control group experienced later first getting out-of-bed time and a longer hospitalization time than the observation group (P<0.05). There was a positive correlation between VAS score and IL-6 as well as Cor before and after treatment (P<0.05). The two groups were similar in treatment expense (P>0.05) and the incidence of adverse reactions (P>0.05). Age and anesthesia scheme were risk factors for postoperative cognitive dysfunction.

CONCLUSION

Nerve block combined with general anesthesia can effectively improve the cognitive function and analgesic effect of elderly patients undergoing knee joint replacement, and accelerate recovery time, without increasing f adverse reactions, and can also accelerate recovery of their cognitive function.

Effect of Acupuncture on the Cognitive Control Network of Patients with Knee Osteoarthritis: Study Protocol for a Randomized Controlled Trial

Purpose

Materials and Methods

Discussion

Study Registration

Diterbutyl phthalate attenuates osteoarthritis in ACLT mice via suppressing ERK/c-fos/NFATc1 pathway, and subsequently inhibiting subchondral osteoclast fusion

Osteoarthritis (OA) is the most common arthritis with a rapidly increasing prevalence. Disease progression is irreversible, and there is no curative therapy available. During OA onset, abnormal mechanical loading leads to excessive osteoclastogenesis and bone resorption in subchondral bone, causing a rapid subchondral bone turnover, cyst formation, sclerosis, and finally, articular cartilage degeneration. Moreover, osteoclast-mediated angiogenesis and sensory innervation in subchondral bone result in abnormal vascularization and OA pain. The traditional Chinese medicine Panax notoginseng (PN; Sanqi) has long been used in treatment of bone diseases including osteoporosis, bone fracture, and OA. In this study we established two-dimensional/bone marrow mononuclear cell/cell membrane chromatography/time of flight mass spectrometry (2D/BMMC/CMC/TOFMS) technique and discovered that diterbutyl phthalate (DP) was the active constituent in PN inhibiting osteoclastogenesis. Then we explored the therapeutic effect of DP in an OA mouse model with anterior cruciate ligament transaction (ACLT). After ACLT was conducted, the mice received DP (5 mg·kg^-1·d^-1, ip) for 8 weeks. Whole knee joint tissues of the right limb were harvested at weeks 2, 4, and 8 for analysis. We showed that DP administration impeded overactivated osteoclastogenesis in subchondral bone and ameliorated articular cartilage deterioration. DP administration blunted aberrant H-type vessel formation in subchondral bone marrow and alleviated OA pain assessed in Von Frey test and thermal plantar test. In RANKL-induced RAW264.7 cells in vitro, DP (20 μM) retarded osteoclastogenesis by suppressing osteoclast fusion through inhibition of the ERK/c-fos/NFATc1 pathway. DP treatment also downregulated the expression of dendritic cell-specific transmembrane protein (DC-STAMP) and d2 isoform of the vacuolar (H+) ATPase V0 domain (Atp6v0d2) in the cells. In conclusion, we demonstrate that DP prevents OA progression by inhibiting abnormal osteoclastogenesis and associated angiogenesis and neurogenesis in subchondral bone.