Update on the epidemiology, risk factors and disease outcomes of osteoarthritis

Cathelicidin antimicrobial peptide (CAMP) gene promoter methylation induces chondrocyte apoptosis

Objective

The occurrence of osteoarthritis is related to genetic and environmental factors. Among them, the change of chondrocyte gene expression pattern regulated by epigenetic modification is an important participant. This study analyzed the effect of CAMP gene methylation on the level of oxidative stress and inflammation of chondrocytes.

Methods

We analyzed the changes of the transcriptome in the articular cartilage tissue of osteoarthritis (OA) patients from the GSE117999 dataset. The GSE48422 dataset was used to analyze the changes in the methylation level of osteoarthritis cells. Cell Counting Kit-8 (CCK-8) and flow cytometry analysis of short hairpin RNA (shRNA) silencing CAMP gene and 5-μM 5-Aza-2’-Deoxycytidine (AZA) treatment on the proliferation and apoptosis of Human chondrocytes osteoarthritis (HC-OA) cells. The Dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay was used to detect the level of reactive oxygen species (ROS), and the expression level of inflammatory factors was analyzed by Western Blot.

Results

The expression of CAMP in cartilage tissue of OA patients was upregulated, and the level of methylation was downregulated. CAMP was highly expressed in osteoarthritis articular cartilage cells. Silencing CAMP inhibited the proliferation of HC-OA cells and promoted their apoptosis. CAMP gene methylation inhibited ROS levels and tumor necrosis factor-α (TNF-α) expression levels in HC-OA cells, and promoted transforming growth factor beta (TGF-β) expression. CAMP gene methylation inhibited the proliferation of HC-OA cells and promoted their apoptosis.

Conclusion

CAMP gene promoter methylation inhibits ROS levels and inflammation and induces chondrocyte apoptosis.

DNA Methylation Signatures of Bone Metabolism in Osteoporosis and Osteoarthritis Aging-Related Diseases: An Updated Review

DNA methylation is one of the most studied epigenetic mechanisms that play a pivotal role in regulating gene expression. The epigenetic component is strongly involved in aging-bone diseases, such as osteoporosis and osteoarthritis. Both are complex multi-factorial late-onset disorders that represent a globally widespread health problem, highlighting a crucial point of investigations in many scientific studies. In recent years, new findings on the role of DNA methylation in the pathogenesis of aging-bone diseases have emerged. The aim of this systematic review is to update knowledge in the field of DNA methylation associated with osteoporosis and osteoarthritis, focusing on the specific tissues involved in both pathological conditions.

MicroRNA-210-3p Promotes Chondrogenic Differentiation and Inhibits Adipogenic Differentiation Correlated with HIF-3α Signalling in Bone Marrow Mesenchymal Stem Cells

Cartilage injury of the knee joint is very common. Due to the limited self-healing ability of articular cartilage, osteoarthritis is very likely to occur if left untreated. Bone marrow mesenchymal stem cells (BMMSCs) are widely used in the study of cartilage injury due to their low immunity and good amplification ability, but they still have disadvantages, such as heterogeneous undifferentiated cells. MicroRNAs can regulate the chondrogenic differentiation ability of MSCs by inhibiting or promoting mRNA translation and degradation. In this research, we primarily investigated the effect of microRNA-210-3p (miR-210-3p) on chondrogenic and adipogenic differentiation of BMMSCs in vitro. Our results demonstrate that miR-210-3p promoted chondrogenic differentiation and inhibited adipogenic differentiation of rat BMMSCs, which was related to the HIF-3α signalling pathway. Additionally, miR-210-3p promotes mRNA and protein levels of the chondrogenic expression genes COLII and SOX9 and inhibits mRNA and protein levels of the adipogenic expression genes PPARγ and LPL. Thus, miR-210-3p combined with BMMSCs is a candidate for future clinical applications in cartilage regeneration and could represent a promising new therapeutic target for OA.

Effect of a prebiotic supplement on knee joint function, gut microbiota, and inflammation in adults with co-morbid obesity and knee osteoarthritis: study protocol for a randomized controlled trial

BACKGROUND

Osteoarthritis (OA) is a chronic and painful condition where the articular cartilage surfaces progressively degenerate, resulting in loss of function and progressive disability. Obesity is a primary risk factor for the development and progression of knee OA, defined as the "metabolic OA" phenotype. Metabolic OA is associated with increased fat deposits that release inflammatory cytokines/adipokines, thereby resulting in systemic inflammation which can contribute to cartilage degeneration. There is currently no cure for OA. Prebiotics are a type of dietary fiber that can positively influence gut microbiota thereby reducing systemic inflammation and offering protection of joint integrity in rodents. However, no human clinical trials have tested the effects of prebiotics in adults with obesity suffering from knee OA. Therefore, the purpose of this double-blind, placebo-controlled, randomized trial is to determine if prebiotic supplementation can, through positive changes in the gut microbiota, improve knee function and physical performance in adults with obesity and knee OA.

METHODS

Adults (n = 60) with co-morbid obesity (BMI > 30 kg/m2) and knee OA (Kellgren-Lawrence grade II-III) will be recruited from the Alberta Hip and Knee Clinic and the Rocky Mountain Health Clinic and surrounding community of Calgary, Canada, and randomized (stratified by sex, BMI, and age) to prebiotic (oligofructose-enriched inulin; 16 g/day) or a calorie-matched placebo (maltodextrin) for 6 months. Anthropometrics, performance-based tests, knee pain, serum inflammatory markers and metabolomics, quality of life, and gut microbiota will be assessed at baseline, 3 months, 6 months (end of prebiotic supplementation), and 3 months following the end of the prebiotic supplementation.

CLINICAL SIGNIFICANCE

There is growing pressure on health care systems for aggressive OA treatment such as total joint replacement. Less aggressive, yet effective, conservative treatment options have the potential to address the growing prevalence of co-morbid obesity and knee OA by delaying the need for joint replacement or ideally preventing its need altogether. The results of this clinical trial will provide the first evidence regarding the efficacy of prebiotic supplementation on knee joint function and pain in adults with obesity and knee OA. If successful, the results may provide a simple, safe, and easy to adhere to intervention to reduce knee joint pain and improve the quality of life of adults with co-morbid knee OA and obesity.

TRIAL REGISTRATION

Clinical Trials.gov NCT04172688 . Registered on 21 November 2019.

Development of a multivariable prediction model for early revision of total knee arthroplasty - The effect of including patient-reported outcome measures

Background

Revision TKA is a serious adverse event with substantial consequences for the patient. As revision is becoming increasingly common in patients under 65 years, the need for improved preoperative patient selection is imminently needed. Therefore, this study aimed to identify the most important factors of early revision and to develop a prediction model of early revision including assessment of the effect of incorporating data on patient-reported outcome measures (PROMs).

Material and methods

A cohort of 538 patients undergoing primary TKA was included. Multiple logistic regression using forward selection of variables was applied to identify the best predictors of early revision and to develop a prediction model. The model was internally validated with stratified 5-fold cross-validation. This procedure was repeated without including data on PROMs to develop a model for comparison. The models were evaluated on their discriminative capacity using area under the receiver operating characteristic curve (AUC).

Results

The most important factors of early revision were age (OR 0.63 [0.42, 0.95]; P = 0.03), preoperative EQ-5D (OR 0.07 [0.01, 0.51]; P = 0.01), and number of comorbidities (OR 1.01 [0.97, 1.25]; P = 0.15). The AUCs of the models with and without PROMs were 0.65 and 0.61, respectively. The difference between the AUCs was not statistically significant (P = 0.32).

Conclusions

Although more work is needed in order to reach a clinically meaningful quality of the predictions, our results show that the inclusion of PROMs seems to improve the quality of the prediction model.

Effects of exercise on knee osteoarthritis: A systematic review

BACKGROUND

Knee osteoarthritis is the most common joint disease and a major cause of functional limitation and pain in adults. The aim of this literature review is to review the existing evidence regarding the impact of exercise in people with knee osteoarthritis concerning physical and functional outcomes. The secondary aim is to provide both healthcare professionals and patients with updated and high-quality recommendations for the management of this condition.

METHODS

A systematic search was performed at Pubmed, Scopus and Web of Science databases, limiting the studies to English, French and Portuguese language, from 2010 to May 2020. Eligible studies were randomized control trials or clinical control trials that compared an intervention consisting of an exercise programme in adult participants with knee osteoarthritis against no intervention.

RESULTS

A total of 4499 studies were retrieved and 19 articles met the inclusion criteria. Beneficial effects of exercise were found on pain and strength. Regarding function, functional performance and quality of life, evidence is controversial. Both strengthening and aerobic exercise showed positive effects and both aquatic and land-based programmes presented improvement of pain, physical function and quality of life. Relatively to stretching, plyometric and proprioception training, no concrete conclusions can be taken.

CONCLUSION

Exercise programmes appear to be safe and effective in knee osteoarthritis patients, mainly regarding pain and strength improvement. Pilates, aerobic and strengthening exercise programmes performed for 8-12 weeks, 3-5 sessions per week; each session lasting 1 h appear to be effective. Both aquatic and land-based programmes show comparable and positive effects.

Challenges and Innovations in Osteochondral Regeneration: Insights from Biology and Inputs from Bioengineering toward the Optimization of Tissue Engineering Strategies

Due to the extremely high incidence of lesions and diseases in aging population, it is critical to put all efforts into developing a successful implant for osteochondral tissue regeneration. Many of the patients undergoing surgery present osteochondral fissure extending until the subchondral bone (corresponding to a IV grade according to the conventional radiographic classification by Berndt and Harty). Therefore, strategies for functional tissue regeneration should also aim at healing the subchondral bone and joint interface, besides hyaline cartilage. With the ambition of contributing to solving this problem, several research groups have been working intensively on the development of tailored implants that could promote that complex osteochondral regeneration. These implants may be manufactured through a wide variety of processes and use a wide variety of (bio)materials. This review aimed to examine the state of the art regarding the challenges, advantages, and drawbacks of the current strategies for osteochondral regeneration. One of the most promising approaches relies on the principles of additive manufacturing, where technologies are used that allow for the production of complex 3D structures with a high level of control, intended and predefined geometry, size, and interconnected pores, in a reproducible way. However, not all materials are suitable for these processes, and their features should be examined, targeting a successful regeneration.

Co-treatment with disulfiram and glycyrrhizic acid suppresses the inflammatory response of chondrocytes

Background

Osteoarthritis (OA) is a kind of systemic musculoskeletal disorder and a most important factor for causing disability and physical painfulness. Nevertheless, due to the fact that OA can be triggered by multiple etiological factors, this disease is hard to be cured. Therefore, it is of great necessity for us to find novel targets or drugs for OA treatment.

Materials and methods

The chondrocytes were treated with lipopolysaccharide (LPS) and adenosine triphosphate (ATP) to induce pyroptosis in OA. The cell proliferation was detected by Cell Counting Kit-8 assay (CCK-8 assay). Enzyme-linked immunosorbent assay (ELISA) was used for the detection of pyroptosis-related inflammatory factors. Then, the antagonists for gasdermin D (GSDMD) (disulfiram) and high mobility group box 1 (HMGB1) (glycyrrhizic acid) were used to treat the cell model to observe the effects of disulfiram and glycyrrhizic acid on the proliferation of chondrocytes in OA. The protein levels of pyroptosis-related inflammatory factors were measured by western blot, and the levels of aldehyde dehydrogenase (ALDH) and reactive oxygen species (ROS) were measured by corresponding commercial kits.

Results

After chondrocytes were induced by LPS and ATP, the cell proliferation was decreased and the expressions of pyroptosis-related inflammatory factors were increased. Disulfiram and glycyrrhizic acid treatment led to enhanced cell proliferation and increased expressions of pyroptosis-related inflammatory factors, while disulfiram showed better alleviative effects on the inflammation in chondrocytes in OA. However, co-treatment with disulfiram at a high concentration and glycyrrhizic acid did not result in higher proliferation of chondrocytes and alleviated inflammation, but led to oxidative stress.

Conclusion

In conclusion, co-treatment with disulfiram and glycyrrhizic acid at a standard concentration suppresses the inflammatory response of chondrocytes, which may provide guidance for the use of the drugs in the treatment of OA.

Effect of Rubus idaeus Extracts in Murine Chondrocytes and Explants

Osteoarthritis is characterized by cartilage loss resulting from the activation of chondrocytes associated with a synovial inflammation. Activated chondrocytes promote an increased secretion of matrix proteases and proinflammatory cytokines leading to cartilage breakdown. Since natural products possess anti-inflammatory properties, we investigated the direct effect of Rubus idaeus extracts (RIE) in chondrocyte metabolism and cartilage loss. The effect of RIE in chondrocyte metabolism was analyzed in murine primary chondrocytes and cartilage explants. We also assessed the contribution of RIE in an inflammation environment by culturing mice primary chondrocytes with the supernatant of Raw 264.7 macrophage-like cells primed with RIE. In primary chondrocytes, RIE diminished chondrocyte hypertrophy (Col10), while increasing the expression of catabolic genes (Mmp-3, Mmp-13) and reducing anabolic genes (Col2a1, Acan). In cartilage explants, Rubus idaeus prevented the loss of proteoglycan (14.84 ± 3.07% loss of proteoglycans with IL1 alone vs. 3.03 ± 1.86% with IL1 and 100 µg/mL of RIE), as well as the NITEGE neoepitope expression. RIE alone reduced the expression of Il1 and Il6 in macrophages, without changes in Tnf and Cox2 expression. The secretome of macrophages pre-treated with RIE and transferred to chondrocytes decreases the gene and protein expression of Mmp-3 and Cox2. In conclusion, these data suggest that RIE may protect from chondrocyte catabolism and cartilage loss in inflammatory conditions. Further evaluations are need before considering RIE as a candidate for the treatment for osteoarthritis.

The gut microbiota in osteoarthritis: where do we stand and what can we do?

Osteoarthritis (OA) is one of the most frequent musculoskeletal diseases characterized by degeneration of articular cartilage, subchondral bone remodeling, and synovial membrane inflammation, which is a leading cause of global disability, morbidity, and decreased quality of life. Interpreting the potential mechanisms of OA pathogenesis is essential for developing novel prevention and disease-modifying therapeutic interventions. Gut microbiota is responsible for a series of metabolic, immunological, and structural and neurological functions, potentially elucidating the heterogeneity of OA phenotypes and individual features. In this narrative review, we summarized research evidence supporting the hypothesis of a “gut-joint axis” and the interaction between gut microbiota and the OA-relevant factors, including age, gender, genetics, metabolism, central nervous system, and joint injury, elucidating the underlying mechanisms of this intricate interaction. In the context, we also speculated the promising manipulation of gut microbiota in OA management, such as exercise and fecal microbiota transplantation (FMT), highlighting the clinical values of gut microbiota. Additionally, future research directions, such as more convincing studies by the interventions of gut microbiota, the gene regulation of host contributing to or attributed to the specific phenotypes of gut microbiota related to OA, and the relevance of distinct cell subgroups to gut microbiota, are expected. Moreover, gut microbiota is also the potential biomarker related to inflammation and gut dysbiosis that is able to predict OA progression and monitor the efficacy of therapeutic intervention.

Gender differences in patient journey to diagnosis and disease outcomes: results from the European Map of Axial Spondyloarthritis (EMAS)

Introduction/objectives

To evaluate the journey to diagnosis, disease characteristics and burden of disease in male and female patients with axial spondyloarthritis (axSpA) across Europe.

Method

Data from 2846 unselected patients participating in the European Map of Axial Spondyloarthritis (EMAS) study through an online survey (2017–2018) across 13 countries were analysed. Sociodemographic characteristics, lifestyle, diagnosis, disease characteristics and patient-reported outcomes (PROs) [disease activity –BASDAI (0–10), spinal stiffness (3–12), functional limitations (0–54) and psychological distress (GHQ-12)] were compared between males and females using chi-square (for categorical variables) and student t (for continuous variables) tests.

Results

In total, 1100 (38.7%) males and 1746 (61.3%) females participated in the EMAS. Compared with males, females reported considerable longer diagnostic delay (6.1 ± 7.4 vs 8.2 ± 8.9 years; p < 0.001), higher number of visits to physiotherapists (34.5% vs 49.5%; p < 0.001) and to osteopaths (13.3% vs 24.4%; p < 0.001) before being diagnosed and lower frequency of HLA-B27 carriership (80.2% vs 66.7%; p < 0.001). In addition, females reported higher degree of disease activity in all BASDAI aspects and greater psychological distress through GHQ-12 (4.4 ± 4.2 vs 5.3 ± 4.1; p < 0.001), as well as a greater use of alternative therapies.

Conclusion

The patient journey to diagnosis of axSpA is much longer and arduous in females, which may be related to physician bias and lower frequency of HLA-B27 carriership. Regarding PROs, females experience higher disease activity and poorer psychological health compared with males. These results reflect specific unmet needs in females with axSpA needing particular attention.

Key Points • Healthcare professionals’ perception of axSpA as a predominantly male disease may introduce some bias during the diagnosis and management of the disease. However, evidence about male-female differences in axSpA is scarce. • EMAS results highlight how female axSpA patients report longer diagnostic delay and higher burden of the disease in a large sample of 2846 participants of 13 European countries. • Results reflect unmet needs of European female patients. Healthcare professionals should pay close attention in order to accurately diagnose and efficiently manage axSpA cases while further research should be developed on the cause of reported gender differences.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10067-020-05558-7.

Disease Burden and Costs in Moderate-to-Severe Chronic Osteoarthritis Pain Refractory to Standard of Care: Ancillary Analysis of the OPIOIDS Real-World Study

Introduction

To determine the disease burden and costs in moderate-to-severe chronic osteoarthritis (OA) pain refractory to standard-of-care treatment in the Spanish National Health System (NHS).

Methods

Ancillary analysis of the OPIOIDS real-world, non-interventional, retrospective, 4-year longitudinal study including patients aged at least 18 years with moderate-to-severe chronic OA pain refractory to standard-of-care with sequential NSAIDs plus opioids. Burden assessment included measurement of analgesia, cognitive functioning, basic activities of daily living, severity and frequency of comorbidities, and all-cause mortality. Costs accounted for healthcare resource utilization and related costs (year 2018).

Results

Records of 13,317 patients were analyzed; 68.9 (14.7) years old, 71.3% (70.5–72.1%) women, 58.1% refractory to NSAID plus weak opioid and 41.9% to NSAID plus strong opioid, accounting for 10.7% (10.5–10.8%) of patients with chronic OA pain. Mean number of comorbidities was 2.9 (1.8) and its severity was 1.8 (1.7). Pain decreased by 0.9 points (12.2%) and cognitive declined by 2.3 points (9.1%, with 4.3% more patients with cognitive deficit) and dependency worsened by 0.4 points (0.5%, with 2.3% more patients with severe-to-total dependence) over a mean treatment period of 188.6 (185.4–191.8) days on NSAIDs followed by 400.6 (393.7–407.5) days on opioids. The adjusted mortality rate was higher in patients with OA taking NSAID plus strong opioids; hazard ratio 1.44 (1.26–1.65; p < 0.001). The 4-year healthcare cost was €7350/patient (€7193–7507 or €1838/year) and was higher in those taking strong versus weak opioids; €9886 (€9608–10,164, €2472/year) vs. €5519 (€5349–5689, €1380/year), p < 0.001. Analgesia cost (16.0% of total cost, 70.2% opioids) was higher with strong versus weak opioids, 19.6% vs. 11.3%, p < 0.001.

Conclusions

In routine clinical practice in Spain, patients with moderate-to-severe chronic OA pain refractory to standard analgesic treatment with NSAIDs plus opioids reported modest reductions in pain, while presenting a considerable burden of comorbidities, cognitive impairment, and dependency. Healthcare costs significantly increased for the NHS particularly with NSAIDs plus strong opioids.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-020-00271-y.

The Value of Serum Adiponectin in Osteoporotic Women: Does Weight Have an Effect?

Osteoporosis (OP) has been observed to have a deleterious effect on postmenopausal women's life quality by increasing the risk of fragility fractures. The current research was adopted to verify the role of serum adiponectin, a cytokine released by adipose tissue, as a marker for OP across different body mass index groups, for a better understanding of fatty tissue role in OP. A case-control study recruited 210 eligible postmenopausal women and subgrouped into three groups based on their DEXA scan results: osteoporotic group, osteopenia group, and healthy controls; each includes 70 patients. Three datasets were collected: anthropometric, age, menopause duration, weight, height, body mass index (BMI), waist circumference, and fat percentage. Radiological examination estimated the bone mineral density (BMD) for the femoral neck and lumbar spines with their respective T-score. From blood, we measured alkaline phosphatase and calcium by a spectrophotometer and serum adiponectin, phosphate, CTX, and PICP by ELIZA. Total BMD, T-score, serum phosphate, and PICP were significantly higher among healthy controls. Serum adiponectin, CTX, and ALP scored higher levels among OP cases. A strong inverse relationship was proved between serum adiponectin and T-score in osteoporotic and osteopenia groups (-0.427, -0.301). A strong negative relationship was found between serum adiponectin and total BMD in healthy controls (-0.204). All correlations were statistically significant, P value <0.001. Serum adiponectin can be a valuable marker for reduced bone mineral density among the general populace, irrespective of the body mass index. Further research is warranted to explore therapeutic and preventive applications for this adipocytokine.

Total-Body PET Imaging of Musculoskeletal Disorders

Imaging of musculoskeletal disorders, including arthritis, infection, osteoporosis, sarcopenia, and malignancies, is often limited when using conventional modalities such as radiography, computed tomography (CT), and MR imaging. As a result of recent advances in Positron Emission Tomography (PET) instrumentation, total-body PET/CT offers a longer axial field-of-view, higher geometric sensitivity, and higher spatial resolution compared with standard PET systems. This article discusses the potential applications of total-body PET/CT imaging in the assessment of musculoskeletal disorders.

Downregulation of miR‑146a inhibits osteoporosis in the jaws of ovariectomized rats by regulating the Wnt/β‑catenin signaling pathway

MicroRNAs (miRNAs or miRs) play important roles in osteoporosis and exhibit high potential in the therapeutic treatment of this condition. The present study aimed to explore the effects of miR-146a on bone loss noted in the jawbones of ovariectomized (OVX) rats and the interaction of miR-146a with the Wnt/β-catenin signaling pathway. OVX Sprague-Dawley female rats were used to establish the animal model of osteoporosis (OP). Bone mineral density (BMD) was measured via dual-energy X-ray and the miR-146a levels were detected by reverse transcription-quantitative PCR. miR-146a antagonist (miR-146a-A) and negative control (miR-146a-NC) were used to examine the effects of miR-146a on OVX rats. The contents of osteocalcin and tartrate resistant phosphatase (TRAP) were detected via ELISA. Hematoxylin and eosin, and TRAP staining were used to observe the pathological changes and the number of osteoclasts in the jawbone, respectively. In addition, the expression levels of the nuclear factor of activated T cells c1 (NFATc1), c-Fos and cathepsin K (CTK) in the jawbone were detected by immunohistochemistry, whereas the expression levels of osteoprotegerin, TRAP, dickkopf1, Wnt2 and β-catenin in the same tissues were assessed by western blot analysis. The Wnt2 activator (DKK2-C2) and inhibitor (endostatin) were used to examine the effects of miR-146a on the Wnt/β-catenin pathway. The results indicated that the BMD was increased, whereas the contents of osteocalcin and TRAP were decreased in the miR-146a-A group compared with those noted in the OP or negative control groups (P<0.05). Although the trabecular bone area of the OP group was decreased, the conditions were improved in the miR-146a-A group. The number of osteoclasts was decreased in the miR-146a-A group compared with that noted in the OP group (P<0.05). The expression levels of NFATc1, c-Fos and CTK in the miR-146a-A group were decreased compared with those noted in the OP or negative control groups (P<0.05). Similar results were found following the comparison of the miR-146a-A group with the DKK2-C2 group. Taken together, these data demonstrated that miR-146a downregulation inhibited OP of the jawbone in OVX rats by activating the Wnt/β-catenin signaling pathway.

Reliability of the assessment of disc degeneration on the lateral DXA scans

INTRODUCTION

Given the prevalence and costs induced by osteoarthritis (OA), it is necessary to find a cheap and safe technique to evaluate it reliably.

OBJECTIVE

To assess the value of the lateral dual energy X-ray absorptiometry (DXA) spine scans for the diagnosis of disc degeneration.

METHOD

Seventy-seven individuals aged 18 and over, with or without disc degeneration, had both lateral thoracolumbar spine radiographs and DXA spine scans (≤6months between both exams). Disc degeneration was assessed using the Lane score. The images of 20 randomly selected individuals were assessed by two readers.

RESULTS

Almost 13% of the thoracic levels were not assessable on the DXA scans. For the identification of the intervertebral levels on the DXA scans as interpretable or not, the intra-reader agreement was good (κ=0.81) and the inter-reader agreement was fair (κ=0.27-0.36). For the diagnostic criteria (osteophytes, disc space narrowing, osteosclerosis, overall grade), the intra-reader agreement was excellent for the radiographs (κ=0.89-0.92), good for the DXA scans (κ=0.64-0.83) and fair to moderate for the between-method comparison (κ=0.25-0.44). The inter-reader agreement was moderate to good for the radiographs (κ=0.49-0.66) and fair to good for the DXA scans (κ=0.32-0.74). In the per patient analysis (the most severe grade), the intra-reader agreement was excellent for the radiographs (κ=0.85-0.94), moderate to excellent for the DXA scans (κ=0.53-0.85) and poor to good for the between-methods comparison (κ=0.17-0.63).

CONCLUSION

Our results do not support the use of DXA scans for the assessment of thoracolumbar disc degeneration.

Statins, bone biology and revision arthroplasty: review of clinical and experimental evidence

Osteoarthritis is a painful, disabling condition which is increasing in prevalence as a result of an ageing population. With no recognized disease-limiting therapeutics, arthroplasty of the hip and knee is the most common and effective treatment for lower limb osteoarthritis, however lower limb arthroplasty has a finite life-span and a proportion of patients will require revision arthroplasty. With increasing life expectancy and an increasing proportion of younger (<65 years) patients undergoing arthroplasty, the demand for revision arthroplasty after implant failure is also set to increase.

Statins are cholesterol-modulating drugs widely used for cardiovascular risk reduction which have been noted to have pleiotropic effects including potentially influencing arthroplasty survival. In vitro studies have demonstrated pleiotropic effects in human bone cells, including enhancement of osteoblastogenesis following simvastatin exposure, and in vivo studies have demonstrated that intraperitoneal simvastatin can increase peri-implant bone growth in rats following titanium tibial implant insertion. There is evidence that statins may also influence osseointegration, enhancing bone growth at the bone–implant interface, subsequently improving the functional survival of implants. Data from the Danish Hip Arthroplasty Registry and the Clinical Practice Research Datalink in the UK suggest a reduction in the risk of lower limb revision arthroplasty in statin ever-users versus never-users, and a time-dependent effect of statins in reducing the risk of revision. In this article we review the clinical and experimental evidence linking statins and risk of revision arthroplasty.

Lower limb kinematics improvement after genicular nerve blockade in patients with knee osteoarthritis: a milestone study using inertial sensors

Background

Genicular nerve blockade is a possible treatment for patients with knee osteoarthritis. Pain relief and improvement in functioning is expected. This procedure could be of major interest for patients in low-income countries where total knee arthroplasty is not available for the population. This study aims at assessing the immediate benefits on pain, gait, and stairs kinematics after a genicular nerve blockade in patients suffering from knee osteoarthritis in Cameroun.

Methods

A prospective study was carried out on 26 subjects in Cameroun. A genicular nerve blockade was performed on 14 women with painful knee osteoarthritis grade 2–4. Lower limb joint angles were recorded with inertial sensors before and 1 h after injection. Patient-reported outcomes of pain and perceived difficulty were collected, as well as 10 m and 6 min walking tests. A reliability analysis of inertial sensors was performed on a sample of 12 healthy subjects by calculating the intraclass correlation coefficient and the standard error of measurement.

Results

Pain and perceived difficulty decreased significantly (p < 0.001). Cadence increased significantly in stairs climbing (upstairs: + 7.7 steps/min; downstairs: + 7.6 steps/min). There was an improvement for hip sagittal range of motion during gait (+ 9.3°) and pelvis transverse range of motion in walking upstairs (− 3.3°). Angular speed range of the knee in the sagittal plane and of the hip in the frontal plane increased significantly in stairs descent (+ 53.7°/s, + 94.5°/s).

Conclusions

This study quantified improvement of gait and stair climbing immediately after a genicular nerve blockade in patients suffering from knee OA in Cameroon. This is the first study objectifying this effect, through wearable sensors.

Trial registration

Pan African Clinical Trial Registry, PACTR202004822698484. Registered 28 March 2020 - Retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-020-03836-8.

Differentiation Antagonizing Non-protein Coding RNA Knockdown Alleviates Lipopolysaccharide-Induced Inflammatory Injury and Apoptosis in Human Chondrocyte Primary Chondrocyte Cells Through Upregulating miRNA-19a-3p

Objective

To confirm the role of long noncoding RNA differentiation antagonizing non‐protein coding RNA (DANCR) in chondrocyte inflammatory injury in osteoarthritis (OA) in vitro, as well as its molecular mechanism.

Methods

Human primary chondrocytes were treated with lipopolysaccharide (LPS) to construct a chondrocyte inflammatory injury in human OA cell model. Gene expression was detected using real‐time quantitative polymerase chain reaction. Cell inflammatory injury was evaluated by Cell Counting Kit‐8 assay, flow cytometry, and enzyme‐linked immunosorbent assay. The interplay between miRNA‐19a‐3p (miR‐19a) and DANCR was validated by dual‐luciferase reporter assay and RNA immunoprecipitation.

Results

Expression of DANCR was upregulated, and miR‐19a was downregulated in human OA cartilage and LPS‐treated primary chondrocytes in vitro. Moreover, DANCR expression was inversely correlated with miR‐19a in OA patients. LPS reduced cell viability and increased the apoptotic rate and secretion of interleukin (IL)‐1β, IL‐6, IL‐8, as well as tumor necrosis factor (TNF)‐α in primary chondrocyte cells in vitro, suggesting an inflammatory injury model of OA. Functionally, knockdown of DANCR could attenuate LPS‐induced apoptosis and inflammatory response, as evidenced by improved cell viability, and reduced apoptotic rate and products of IL‐1β, IL‐6, IL‐8, and TNF‐α. Notably, DANCR negatively regulated miR‐19a expression, presumably via sponging. Furthermore, miR‐19a deletion eliminated the effect of DANCR knockdown on apoptosis and the inflammatory response of primary chondrocytes under LPS stress.

Conclusion

Differentiation antagonizing non‐protein coding RNA silencing could protect human chondrocyte cells against LPS‐induced inflammatory injury and apoptosis through targeting miR‐19a, suggesting a vital role of the DANCR/miR‐19a axis in OA.

Impairment in locomotor activity as an objective measure of pain and analgesia in a rat model of osteoarthritis

A major problem with current animal models of pain is their lack of face validity and their vulnerability for false positive results. The present study evaluated the efficacy of the open field locomotor system, as an objective measure of pain-related behavior and analgesic efficacy in rodents. Adult, male, Sprague-Dawley rats (180-250 g) received intra-articular injections of monoiodoacetate (MIA; 1 mg) in the left knee joint. Mechanical allodynia using von Frey filaments, the weight bearing difference test and the open field locomotor activity test were performed every other day for 21 days, following the MIA injection. The antinociceptive effects of ibuprofen (50 and 100 mg/kg) on the MIA-induced nociception were also evaluated. MIA induced a significant reduction in the paw withdrawal threshold (PWT) and a significant alteration in the weight bearing difference compared with control rats. Similarly, MIA induced a significant reduction in locomotor activity, with respect to X total counts, that represent the overall locomotor activity in the horizontal plane, and X ambulatory counts, which in turn represent small scale movements, such as scratching and grooming, and lastly, Z total counts, that represent rearing or standing. Both doses of ibuprofen resulted in a significant reversal of the MIA-induced alterations in PWT and weight bearing difference. Furthermore, the two doses of ibuprofen resulted in a significant reversal of the MIA-induced reduction in locomotor activity, with respect to X ambulatory counts, but not Z total counts. Only the higher dose of ibuprofen reversed the X total counts. The open field locomotor system may successfully be used to predict the analgesic efficacy of compounds in models of joint inflammation and osteoarthritis.

The Role of Autophagy in Osteoarthritis

Chondrocytes are the only cell type in normal cartilage. The pathological changes of osteoarthritis (OA) mostly revolve around the apoptosis and dysfunction of chondrocytes. Autophagy, as an intracellular degradation system that maintains the steady state of energy metabolism in cells, has been shown to restore the function of damaged chondrocytes, alleviating the occurrence and progression of OA. In this review, we explored the relationship between autophagy and OA and the key molecules of autophagy pathway that regulate the progression of OA, providing new ideas for OA treatment by targeting autophagy.

Pre-TKR isokinetic quadriceps strengthening has a positive effect which may diminish following the intervention despite pain and functional improvements: A case study

We report a longitudinal survey of a 53-year-old man suffering from right knee osteoarthritis who has undergone total knee replacement (TKR). We aimed at evaluating the effect of a short preoperative isokinetic strengthening program on the functional status, pain, and quadriceps and hamstrings strength before and after TKR. The patient performed a 4-week (6 sessions) preoperative isokinetic strengthening program of the quadriceps and hamstrings. The findings for the concentric strength at 60∘/s, 6-minute walk test (6MWT), and Knee injury and Osteoarthritis Outcome Score (KOOS) were recorded. At baseline the patient presented with an overall KOOS score of 44%, a 6MWT of 444 m, a 63% and 21% strength deficits of the quadriceps and hamstrings, respectively. Following the strengthening program, the quadriceps strength of the operated limb improved (+121 Nm; +83%), but the function as reflected by the KOOS score remained unchanged. Following the TKR, the concentric isokinetic strength of the quadriceps reappeared altered (63% of deficit) despite pain and functional improvements. This case report underlines the importance of functional evaluation rather than the maximal strength to assess the effectiveness of TKR. However, further studies are necessary to conceptualize the meaning of maximal strength measurement and the impact of associated deficits, if any.

TAP2, a peptide antagonist of Toll-like receptor 4, attenuates pain and cartilage degradation in a monoiodoacetate-induced arthritis rat model

Because inflammation in osteoarthritis (OA) is related to the Toll-like receptor 4 (TLR4) signaling cascades, TLR4 is a reasonable target for developing therapeutics for OA. Thus, we investigated whether TAP2, a peptide antagonist of TLR4, reduces the monoiodoacetate (MIA)-induced arthritic pain and cartilage degradation in rats. TLR4 expression of human OA chondrocytes and synoviocytes and the knee joint tissue of MIA-induced arthritis were evaluated. MIA-induced arthritic model using Sprague–Dawley rats (6 week-old-male) were treated with TAP2, a TLR4 antagonist, and evaluated with behavioral test, immunohistochemistry, and quantitative PCR. TLR4 was highly expressed in the knee joints of patients with OA and the MIA-induced rat model. Further, a single intraarticular injection of TAP2 (25 nmol/rat) molecules targeting TLR4 on day 7 after MIA injection dramatically attenuated pain behavior for about 3 weeks and reduced cartilage loss in the knee joints and microglial activation in the spinal dorsal horns. Likewise, the mRNA levels of TNFα and IL-1β, reactive oxygen species, and the expression of MMP13 in the knee joints of TAP2-treated rats was significantly decreased by TAP2 treatment compared with the control. Moreover, interestingly, the duration of OA pain relief by TAP2 was much longer than that of chemical TLR4 antagonists, such as C34 and M62812. In conclusion, TAP2 could effectively attenuate MIA-induced arthritis in rats by blocking TLR4 and its successive inflammatory cytokines and MMP13. Therefore, TAP2 could be a prospective therapeutic to treat patients with OA.

Tai Chi exercise can ameliorate physical and mental health of patients with knee osteoarthritis: systematic review and meta-analysis

OBJECTIVE

To systematically review the effects of Tai Chi exercise as a nonpharmacological therapeutic strategy on the physical and mental health in individuals with knee osteoarthritis.

DATA SOURCES

A systematic literature retrieval has been conducted in PubMed, Web of Science, EMbase, CENTRAL, OVID, CINAHL, Physiotherapy Evidence Database, Chinese Biomedical Database and China National Knowledge Infrastructure up to June 2020 to identify the relevant randomised controlled trials (RCTs).

METHODS

Two authors assessed independently the risk of bias using the Cochrane Collaboration's tool. Standardised mean difference (SMD) and 95% CI were calculated and data were combined using the fixed or random-effect model. The strength of evidence was rated with Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

A total of 16 RCTs involving 986 patients with knee osteoarthritis met the established inclusion criteria. The strength of evidence for the main outcomes was low or moderate. The systematic review illustrated the efficacy of Tai Chi exercise in treating and managing knee osteoarthritis. Patients' outcomes practising Tai Chi exercise were improved significantly, including pain (SMD = ‒0.69, 95%CI: ‒0.95 to ‒0.44, P < 0.001), stiffness (SMD = ‒0.59, 95%CI: ‒0.91 to ‒0.27, P < 0.001), physical function (SMD = ‒0.92, 95%CI: -1.16 to ‒0.69, P < 0.001), dynamic balance (SMD = 0.69, 95%CI: 0.38 to 0.99, P < 0.001), physiological and psychological health (SF-36 PCS: SMD = 0.48, 95%CI: 0.28 to 0.68, P < 0.001; SF-36 MCS: SMD = 0.26, 95%CI: 0.06 to 0.45, P = 0.01). No adverse events associated with Tai Chi exercise were reported.

CONCLUSION

Tai Chi exercise was beneficial for ameliorating physical and mental health of patients with knee osteoarthritis and should be available as an alternative non-pharmacological therapy in rehabilitation programmes.

Health outcomes and costs in patients with osteoarthritis and chronic pain treated with opioids in Spain: the OPIOIDS real-world study

Objective:

The objective of this study was to analyze health outcomes, resource utilization, and costs in osteoarthritis patients with chronic nociceptive pain who began treatment with an opioid in real-world practice in Spain.

Methods:

We designed a non-interventional, retrospective, longitudinal study with 36 months of follow-up using electronic medical records (EMRs) from primary care centers, of patients aged 18+ years who began a new treatment with an opioid drug in usual practice for chronic pain due to osteoarthritis. Health/non-health resource utilization and costs, treatment adherence, pain change, cognitive functioning, and dependence for basic activities of daily living (BADL) were assessed.

Results:

A total of 38,539 EMRs [mean age (SD); 70.8 (14.3) years, 72.3% female; 53.3% hip/knee, 25.0% spine, and 21.7% other sites] were recruited. A total of 19.1% of patients remained on initial opioid at 36 months, without significant differences by osteoarthritis site (p = 0.125). Mean total adjusted cost was €17,915, with 27.7% corresponding to healthcare resources and 72.3% to lost productivity. Hospital admissions for osteoarthritis-related surgical interventions accounted for 15.8% of total healthcare cost. A slight mean pain reduction was observed: –1.3 points, –16.9%, p < 0.001, with increases in cognitive deficit (+3.3%, p < 0.001) and moderate to total dependence for BADL (+15.6%, p < 0.001) in a median duration of opioid use of 203 days (IQR: 89–696).

Conclusions:

In real-world practice in Spain, opioid use in osteoarthritis was high, but with low adherence. There were meaningful increases in resource use and costs for the National Health System. Pain reduction was modest, whereas cognitive impairment and dependence for BADL increased significantly.

Limiting the Risk of Osteoarthritis After Anterior Cruciate Ligament Injury: Are Health Care Providers Missing the Opportunity to Intervene?

OBJECTIVE

To understand what sports orthopedic surgeons (OS), primary care physicians (PCPs) with sports medicine training, and physical therapists (PTs) managing nonelite athletes with anterior cruciate ligament (ACL) injury tell their patients about their osteoarthritis (OA) risk.

METHODS

An electronic survey was distributed by the Canadian Academy of Sport and Exercise Medicine (PCPs, OS), the Sports and Orthopedic Divisions of the Canadian Physiotherapy Association (PTs), and to OS identified through the Royal College of Physicians and Surgeons and the Canadian Orthopaedic Association. The survey included 4 sections: demographics, factors discussed, timing of discussions, and discussion of risk factors and their management. Proportions or means with 95% confidence intervals were calculated.

RESULTS

A total of 501 health care professionals (HCPs) responded (98 PCPs, 263 PTs, and 140 OS). Of those responding, 70-77% of physicians reported always discussing OA risk, but only 35% of PTs did. All HCPs reported that patient activities perceived as detrimental to knee health, ACL reinjury, and simultaneous injury to other structures in the knee were most often the reason for discussing OA risk. OA risk was discussed at initial management post-injury (65-94%), with few discussing risk subsequently. Eighty percent of physicians and 99% of PTs indicated that PTs were suited to provide OA risk and management information.

CONCLUSION

HCPs routinely managing people with ACL injury do not consistently discuss OA risk post-injury with them. Educational strategies for HCPs are urgently needed to develop care pathways inclusive of support for OA risk management following ACL injury.

High follicle-stimulating hormone levels accelerate cartilage damage of knee osteoarthritis in postmenopausal women through the PI3K/AKT/NF-κB pathway

Osteoarthritis is the main cause of pain and disability in the elderly, with the most commonly affected joint being the knee. The prevalence of knee osteoarthritis (KOA) is significantly increased in postmenopausal women, although the mechanisms underlying KOA remain unclear. The present study aimed to investigate the association between follicle‐stimulating hormone (FSH) and postmenopausal women with KOA aged between 50 and > 70 years, as well as explore its underlying molecular mechanisms. Here, we report that the 50–60 years age group had the highest level of serum FSH. Compared to the low FSH group (< 40 mIU·mL⁻¹) in the same age group, the high FSH group (> 40 mIU·mL⁻¹) showed more severe cartilage damage. Furthermore, phosphorylated (p)‐phosphoinositide 3‐kinase (PI3K)/PI3K, p‐AKT/AKT and p‐nuclear factor kappa B (NF‐κB)/NF‐κB levels were significantly higher in the high FSH group compared to the low FSH group. Immunofluorescence experiments showed that FSH stimulation promoted the translocation of NF‐κB p65 into the nucleus, and decreased type II collagen and aggrecan in ATDC5 cells. Moreover, we used western blotting in ATDC5 cells to demonstrate that FSH decreased type II collagen and increased p‐PI3K/PI3K, p‐AKT/AKT, p‐NF‐κB/NF‐κB and p‐IKB/IKB in a concentration‐dependent manner. Our results suggest that increased FSH levels are associated with KOA for postmenopausal women aged 50–60 years and that high FSH levels might damage the cartilage tissues through the PI3K/AKT/NF‐κB pathway.

The Burden of Pain Associated with Osteoarthritis in the Hip or Knee from the Patient's Perspective: A Multinational Cross-Sectional Study

Introduction

To evaluate, from the patient’s perspective, the burden of pain associated with hip/knee osteoarthritis (OA) in the USA and selected European Union (EU) countries.

Methods

Data were drawn from the 2017 global Adelphi OA Disease Specific Programme™ (DSP). Patients with hip/knee OA were stratified based on pain intensity and the presence/absence of current opioid use. Outcomes included Western Ontario and McMaster Universities Osteoarthritis Index scores, functional limitations, unmet treatment needs, Charlson Comorbidity Index, relevant comorbid conditions, the 5-dimension 5-level EuroQol, and the Work Productivity and Activity Impairment Questionnaire: Specific Health Problem. Bivariate testing compared outcomes using patients with no/mild pain without opioid use as the reference group.

Results

The study population comprised 2170 patients (US: n = 623 [28.7%]; EU: n = 1547 [71.3%]) with knee (54.9%), hip (24.6%), or knee/hip (20.5%) OA. Mean (SD) age was 66.4 (11.2) years. Patients had no/mild pain without opioid use (39.6%), no/mild pain with opioid use (10.2%), moderate/severe pain without opioid use (30.6%), and moderate/severe pain with opioid use (19.7%). Compared with the reference group, patients with moderate/severe pain reported significantly (p < 0.05) higher functional limitations, greater use of ≥ 3 treatments and treatment dissatisfaction, reduced quality of life, and impaired work productivity and activity. The burden was highest with moderate/severe pain with opioid use. Results were generally similar in the US and EU cohorts.

Conclusions

The results from this multinational cross-sectional study indicate that the impact of OA pain is multidimensional, worsened by increasing pain intensity, and may not be adequately addressed by current treatment strategies.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01445-4) contains supplementary material, which is available to authorized users.

3-T T2 mapping magnetic resonance imaging for biochemical assessment of normal and damaged glenoid cartilage: a prospective arthroscopy-controlled study

This study evaluated the ability of T2 mapping to assess the glenoid cartilage using arthroscopy as the gold standard. Eighteen consecutive patients (mean age: 52.4 ± 14.72 years, including 12 men) with shoulder pain underwent T2 mapping at 3-T with subsequent shoulder arthroscopy. With correlation to cartilage-sensitive morphologic sequences regions-of-interest were placed in the corresponding T2 maps both in normal-appearing cartilage and focal cartilage lesions using a quadrant-wise approach. Inter-reader and intra-reader correlation coefficients (ICCs) between two independent radiologists as well as cut-off values with their sensitivities/specificities for the detection of cartilage damage were calculated. The mean T2 value for healthy cartilage was 23.0 ± 3 ms with significantly higher values in the superior quadrants compared to the inferior quadrants (p < 0.0001). In 5 patients with focal cartilage damage significantly higher T2 values of 44.7 ± 3.7 ms (P < 0.01) were observed. The maximum T2 value in normal cartilage (27.3 ms) was lower than the minimum value in damaged cartilage (40.8 ms) resulting in perfect sensitivities/specificities of 100% (95% confidence-interval 47.8-100.0) for all cut-off values between 27.3-40.8 ms. ICCs ranged between 0.63 and 0.99. In conclusion, T2 mapping can evaluate biochemical cartilage integrity and discriminates arthroscopy-proven healthy and damaged glenoid cartilage with high diagnostic performance.

Modified frailty index as a predictor of the long-term functional result in patients undergoing primary total hip arthroplasty

OBJECTIVES

Total hip arthroplasty (THA) is a well-approved method for the treatment of end-stage osteoarthritis (OA). Due to rising life expectancy, elderly patients burdened with multimorbidity are subjected to THA. Some of these patients present significant depletion of physiological reserves, which is described as the frailty syndrome. This study aims to assess the influence of frailty on the THA outcomes in OA patients.

MATERIAL AND METHODS

A single-center observational study was conducted to investigate the effect of frailty measured by the modified frailty index-5 (mFI-5) and modified frailty index-11 (mFI-11) on the long-term post-THA outcomes. The analysis included 597 initially screened patients subjected to unilateral, primary THA due to hip OA. The outcomes were assessed during a follow-up visit 3 years after THA. The primary outcome measures were patient-reported (the Western Ontario and McMaster Universities Osteoarthritis Index - WOMAC) and physician-reported scales (the Harris Hip Score - HHS). The secondary outcome measures were the length of hospital stay (LOS), pain complaints, complications, and satisfaction. A correlation analysis was performed (Spearman's R).

RESULTS

Three hundred sixty-five patients met the eligibility criteria, including 57.26% women (n = 209) and 42.74% men (n = 156). The mean age was 65.11 ±12.12 years. Patients with high values of mFI-5 (r = 0.19; p < 0.05) and mFI-11 (r = 0.22; p < 0.01) achieved less satisfactory functional outcomes after THA (WOMAC). After age adjustment, mFI-11 (r = 0.17; p < 0.05) was a better predictor of functional outcome (WOMAC) than mFI-5 was (r = 0.15; p = 0.07). The mFI-5 (r = 0.25; p < 0.001) and mFI-11 (r = 0.29; p < 0.001) correlated with longer LOS.

CONCLUSIONS

The modified frailty index-5 (mFI-5) and modified frailty index-11 (mFI-11) are useful tools to identify patients subjected to THA at a high risk of poor functioning after the procedure. They can be used in preoperative counseling before obtaining informed consent to support surgical decision-making. To our knowledge, this is the first study investigating the impact of the mFI on long-term postoperative functional results in OA treated with THA.

Evaluation of Long-Time Decoction-Detoxicated Hei-Shun-Pian (Processed Aconitum carmichaeli Debeaux Lateral Root With Peel) for Its Acute Toxicity and Therapeutic Effect on Mono-Iodoacetate Induced Osteoarthritis

Background

As a degenerative joint disease with severe cartilage destruction and pain, osteoarthritis (OA) has no satisfactory therapy to date. In traditional Chinese medicine (TCM), Aconitum carmichaeli Debeaux derived Hei-shun-pian (Hsp) has been developed for joint pain treatment. However, it causes adverse events in OA patients. Long-time decoction has been traditionally applied to reduce the aconite toxicity of Hsp and other aconite herbs, but its detoxifying effect is uncertain.

Methods

Hsp was extracted with dilute decoction times (30, 60, and 120 min) and evaluated by toxicological, chemical, pharmacological assays. Acute toxicity assay and chemical analysis were employed to determine the toxicity and chemoprofile of Hsp extracts, respectively. Since the detoxified Hsp (dHsp) was defined, its therapeutic effect was evaluated by using an OA rat model induced by monosodium iodoacetate. dHsp at 14 g/kg was orally administered for 28 days, and the pain assessments (mechanical withdrawal threshold and thermal withdrawal latency) and histopathological analyses (HE and safranin-O staining) were performed. Real-time PCR (qPCR) was applied to determine the molecular actions of dHsp on cartilage tissue and on chondrocytes. MTT assay was conducted to evaluate the effect of dHsp on the cell viability of chondrocytes. The cellular and molecular assays were also conducted to analyze the functions of chemical components in dHsp.

Results

The chemoprofile result showed that the contents of toxic alkaloids (aconitine, mesaconitine, and hypaconitine) were decreased but that of non-toxic alkaloids (benzoylaconitine, benzoylmesaconitine, and benzoylhypaconitine) were increased with increasing decoction time. Acute toxicity assay showed that only Hsp extract with 120 min decoction was non-toxic within the therapeutic dose range. Thus, it was defined as dHsp for further experiment. In OA experiment, dHsp significantly attenuated joint pain and prevented articular degeneration from MIA attack. qPCR data showed that dHsp restored the abnormal expressions of Col10, Mmp2, Sox5, Adamts4/5/9, and up-regulated Col2 expression in rat cartilage. In vitro, dHsp-containing serum significantly proliferated rat chondrocytes and regulated the gene expressions of Col2, Mmp1, Adamts9, and Aggrecan in a similar way as the in vivo data. Moreover, aconitine, mesaconitine, and hypaconitine exerted cytotoxic effects on chondrocytes, while benzoylaconitine and benzoylhypaconitine except benzoylmesaconitine exhibited similar molecular actions to dHsp, indicating contributions of benzoylaconitine and benzoylhypaconitine to dHsp.

Conclusions

This study defined dHsp and demonstrated dHsp as a potential analgesic and disease modifying agent against OA with molecular actions on the suppression of chondrocyte hypertrophy and extracellular matrix degradation, providing a promising TCM candidate for OA therapy.

Purinergic System Signaling in Metainflammation-Associated Osteoarthritis

Inflammation triggered by metabolic imbalance, also called metainflammation, is low-grade inflammation caused by the components involved in metabolic syndrome (MetS), including central obesity and impaired glucose tolerance. This phenomenon is mainly due to excess nutrients and energy, and it contributes to the pathogenesis of osteoarthritis (OA). OA is characterized by the progressive degeneration of articular cartilage, which suffers erosion and progressively becomes thinner. Purinergic signaling is involved in several physiological and pathological processes, such as cell proliferation in development and tissue regeneration, neurotransmission and inflammation. Adenosine and ATP receptors, and other members of the signaling pathway, such as AMP-activated protein kinase (AMPK), are involved in obesity, type 2 diabetes (T2D) and OA progression. In this review, we focus on purinergic regulation in osteoarthritic cartilage and how different components of MetS, such as obesity and T2D, modulate the purinergic system in OA. In that regard, we describe the critical role in this disease of receptors, such as adenosine A2A receptor (A2AR) and ATP P2X7 receptor. Finally, we also assess how nucleotides regulate the inflammasome in OA.

The β-catenin/TCF-4 pathway regulates the expression of OPN in human osteoarthritic chondrocytes

BACKGROUND

Cartilage destruction is the main characteristic of osteoarthritis (OA), and osteopontin (OPN) is elevated in OA articular cartilage; however, the reason for the increased OPN level is not determined. In addition, Wnt/β-catenin signaling participates in the progression of OA. The aim of the present study was to evaluate whether canonical Wnt signaling could regulate the expression of OPN in human chondrocytes in vitro.

METHODS

Human chondrocytes were cultured in vitro, and we first assayed the mRNA levels of OPN and β-catenin in chondrocytes. Next, we performed transient transfection of TCF 4 shRNA into chondrocytes to inhibit TCF 4 expression and explore changes in the OPN level. Then, the Wnt/β-catenin signaling inhibitor Dickkopf-1 (Dkk-1) was incubated with chondrocytes, and we assayed the changes in β-catenin and OPN.

RESULTS

Our results showed that the expression of both β-catenin and OPN was increased in OA chondrocytes, but there were no correlations between β-catenin and OPN expression. TCF4 shRNA downregulated the expression of TCF 4 and OPN in chondrocytes, while after treatment with rDKK-1 at a concentration of 400 ng/ml for 24 h, the mRNA and protein expression of both β-catenin and OPN was significantly decreased in chondrocytes.

CONCLUSIONS

Elevated OPN expression might be regulated by the β-catenin/TCF-4 pathway, and the Wnt/β-catenin inhibitor DKK1 could inhibit the expression of β-catenin and OPN in OA chondrocytes.

Core Outcome Measurement Instruments for Clinical Trials of Total Knee Arthroplasty: A Systematic Review

(1) Background: We have updated knowledge of the psychometric qualities of patient-reported outcome measures and, for the first time, systematically reviewed and compared the psychometric qualities of physical tests for patients with knee osteoarthritis who are undergoing total knee arthroplasty. This work was conducted to facilitate the choice of the most appropriate instruments to use in studies and clinical practice. (2) Methods: A search of medical databases up to December 2019 identified the studies and thus the instruments used. The quality of the measurement properties was assessed by the Bot et al. criteria. (3) Results: We identified 20 studies involving 25 instruments. Half of the instruments were questionnaires (n = 13). Among the condition-specific instruments, the Oxford knee score, Knee injury and Osteoarthritis Outcomes Score, and the Western Ontario and McMaster Universities Osteoarthritis index had the highest overall scores. Concerning generic tools, the Medical Outcomes Study Short-Form 36 (SF-36) or SF-12 obtained the highest overall score. For patient-specific tools, the Hospital Anxiety and Depression Scale ranked the highest. Some physical tests seemed robust in psychometric properties: 6-min Walk Test, five times Sit-To-Stand test, Timed Up and Go test strength testing of knee flexor/extensor by isometric or isokinetic dynamometer and Pressure Pain Threshold. (4) Conclusion: To make stronger recommendations, key areas such as reproducibility, responsiveness to clinical change, and minimal important change still need more rigorous evaluations. Some promising physical tests (e.g., actimetry) lack validation and require rigorous studies to be used as a core set of outcomes in future studies.

Research Trends of Acupuncture Therapy on Knee Osteoarthritis from 2010 to 2019: A Bibliometric Analysis

Background

Acupuncture has been widely applied to relieve knee osteoarthritis (KOA) in many countries. However, the bibliometric analysis of the global use of acupuncture on KOA is largely unknown. Therefore, this study aimed to explore the current status and trends of the global use of acupuncture on KOA in recent 10 years by using CiteSpace (5.6.R3).

Methods

Publications regarding acupuncture therapy for treating KOA between 2010 and 2019 were extracted from the Web of Science database. CiteSpace was used to analyze the number of publications, countries, institutions, journals, authors, cited references and keywords by using standard bibliometric indicators.

Results

A total of 343 publications were retrieved from 2010 to 2019. The total number of publications continually increased over the past four years, and the most active journals, countries, institutions and authors in the field of acupuncture therapy on patients with KOA were identified. The Evid Based Complement Alternat Med (28) was the most prolific journal, and the Ann Intern Med (202) was the most cited journal. The most productive country and institution in this field was China (115) and University of York (18), respectively. Hugh Macpherson (18) was the most prolific author and Witt C ranked the first in the cited authors. In the ranking of frequency in cited reference, the first article was published by Scharf HP (54). The keyword of ‘randomized controlled trial’ ranked first for research developments with the highest citation burst (3.9486). Besides, there were three main frontiers in keywords for KOA research, including ‘research method, ‘age’ and ‘measure of intervention’.

Conclusion

The findings from this bibliometric study provide current status and trends in clinical research of acupuncture therapy on patients with KOA over the past ten years, which may help researchers identify hot topics and explore new directions for future research in this field.

Elucidation of the Mechanism by Which a ADAMTS5 Gene MicroRNA-Binding Site Single Nucleotide Polymorphism Affects the Risk of Osteoarthritis

Purpose: The aim of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) within the 3' untranslated region of the microRNA (miRNA)-binding site of the ADAM metallopeptidase with thrombospondin type 1 motif 5 (ADAMTS5) gene and the risk of knee osteoarthritis (KOA) and its mechanism. Materials and Methods: Sanger sequencing was used to determine the genotypes of three ADAMTS5 gene SNPs (rs3171407, rs229071, and rs229077) from 310 patients suffering from osteoarthritis of the knee joint (KOA) and 310 healthy controls. The levels of the miRNAs, thsa-miR-103b, hsa-miR-144-3p, and hsa-miR-105-5p in plasma, and the level of ADAMTS5 mRNA in the articular cartilage of 132 patients with KOA were detected by real-time quantitative PCR. Results: The G allele at the rs3171407 locus of the ADAMTS5 gene was demonstrated to be a protective genetic factor for KOA. In addition, the risk of developing KOA was significantly increased in subjects carrying the C allele at the rs229071 locus. The risk of developing KOA in carriers of the G allele at locus rs229077 was 1.49 times greater than those with the A allele. The level of the hsa-miR-144-3p was increased, and the expression level of the ADAMTS5 protein was decreased in carriers of the T allele at the rs229071 locus. In carriers of rs229077 locus A allele the hsa-miR-105-5p level was increased and the expression level of ADAMTS5 protein was decreased. Conclusion: SNPs at the rs3171407, rs229071, and rs229077 loci of the ADAMTS5 gene are related to the risk of OA. The likely mechanism underlying these observations is that these SNPs affect the regulation of ADAMTS5 protein expression through miRNAs; however, this needs to be verified using in vivo models.

Association study of the functional variants of the GLIS3 gene with risk of knee osteoarthritis

INTRODUCTION/OBJECTIVES

Osteoarthritis (OA) ranks the most common joint disorder and the leading cause of disability. Growing evidence has revealed that OA has a strong genetic background, except for aging and obesity. The aim of this study is to determine the associations between potential functional variants of the GLIS3 and GLIS3-AS1 gene and risk of knee OA among a Chinese population.

METHODS

In this case-control study with 810 knee OA cases and 900 healthy controls, seven selected functional SNPs of the GLIS3 and GLIS3-AS1 gene were evaluated.

RESULTS

We found minor alleles of rs10116772 (OR: 0.80, 95% CI: 0.69-0.92, P = 0.002), rs7045410 (OR: 0.74, 95% CI: 0.61-0.92, P = 0.005), and rs7032713 (OR: 0.76, 95% CI: 0.63-0.93, P = 0.006) were significantly associated with decreased risk of knee OA. Results of the dominant and recessive model, stratified analyses using Kellgren-Lawrence (KL) grading presented that the significant associations were not materially changed. Haplotype analysis indicated that haplotype CGT (OR: 0.66, 95% CI: 0.46-0.96, P = 0.031) and ATT (OR: 0.76, 95% CI: 0.6-0.95, P = 0.017) were significantly associated with decreased risk of knee OA. Further, they were also significantly associated with lower expression level of GLIS3, as well as higher expression level of GLIS3-AS1 in the articular cartilage specimens. Genotype-tissue expression (GTEX) data also validated that minor alleles of rs7045410 and rs7032713 were significantly associated with higher expression level of GLIS3-AS1 in thyroid and pituitary tissues (P < 0.001).

CONCLUSIONS

These findings revealed the essential role of genetic variants of the GLIS3 and GLIS3-AS1 gene in the occurrence of knee OA together. Key Point • Functional variants of the GLIS3 and GLIS3-AS1 gene were significantly associated with decreased risk of knee OA.

Short-Term Effect of a New Oral Sodium Hyaluronate Formulation on Knee Osteoarthritis: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

Objective: the aim of this pilot study was to test the short-term effect of oral supplementation with a sodium hyaluronate with a large spectrum of molecular weights (FS-HA^®) on the symptoms and functionality of knee osteoarthritis (OA). Methods: 60 subjects affected by clinical and/or radiological diagnosis of symptomatic knee OA were consecutively enrolled in a randomized, double blind, placebo-controlled, clinical trial. At randomization visit, at day 28 (visit 2), and day 56 (visit 3), the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), the Lequesne Functional Index (LFI) and the Visual Analogue Scale (VAS) for pain (VAS-p) were administered to the enrolled patients. Then, patients were asked how many times they used rescue medications (non-steroidal antinflammatory drugs–NSAIDs and/or anti-pain drugs) during the previous 4 weeks. Finally, the range of knee joint motion (ROM) was also instrumentally measured. Results: In FS-HA^® treated subjects, VAS-p, pain and total WOMAC score, LFI and ROM significantly improved compared to the baseline values (p < 0.05). At 60 days, the VAS-p and the pain WOMAC score were significantly lower after FS-HA^® treatment when compared with placebo as well (p < 0.05). The FS-HA^® treated subjects significantly reduced the weekly use of NSAIDs and/or antipain drugs when compared to the placebo-treated ones (p < 0.05). Conclusion: the oral supplementation with a FS-HA^® characterized by a large spectrum of molecular weight was associated with a short-term improvement in symptomatology and functionality of osteoarthritis-affected knees, and associated with a reduction in the use of NSAIDS and anti-pain drugs.

Perioperative Pain Management in Patients Undergoing Total Hip Arthroplasty: Where Do We Currently Stand?

Total Hip replacement (THR) is a well-discussed topic, and it offers excellent results in patients suffering from end-stage osteoarthritis (OA). However, despite the fact that patients can fully bear weight immediately after the surgery, THR is often associated with a great amount of postoperative pain affecting recovery and rehabilitation. Therefore, the efficient management of pain is of paramount importance. The aim of this review is to examine all the currently available strategies of pain management such as preemptive analgesia (PA), patient-controlled analgesia (PCA), and the various types of anesthesia that are used during the operation. With that objective in mind, we conducted our research by searching through the PubMed database for articles published in 2015 and after. For purely clinical reasons, we have attempted to classify all the best available evidence into three major categories: prior to surgery, during the surgery, and after the surgery. Multimodal analgesia seems to play a major role in the perioperative care of patients undergoing total hip arthroplasty (THA). Therefore, a considerable number of studies have been conducted analyzing all the current strategies that aim to minimize perioperative pain and consequent complications.

Herbal Remedies as Potential in Cartilage Tissue Engineering: An Overview of New Therapeutic Approaches and Strategies

It is estimated that by 2023, approximately 20% of the population of Western Europe and North America will suffer from a degenerative joint disease commonly known as osteoarthritis (OA). During the development of OA, pro-inflammatory cytokines are one of the major causes that drive the production of inflammatory mediators and thus of matrix-degrading enzymes. OA is a challenging disease for doctors due to the limitation of the joint cartilage's capacity to repair itself. Though new treatment approaches, in particular with mesenchymal stem cells (MSCs) that integrate the tissue engineering (TE) of cartilage tissue, are promising, they are not only expensive but more often do not lead to the regeneration of joint cartilage. Therefore, there is an increasing need for novel, safe, and more effective alternatives to promote cartilage joint regeneration and TE. Indeed, naturally occurring phytochemical compounds (herbal remedies) have a great anti-inflammatory, anti-oxidant, and anabolic potential, and they have received much attention for the development of new therapeutic strategies for the treatment of inflammatory diseases, including the prevention of age-related OA and cartilage TE. This paper summarizes recent research on herbal remedies and their chondroinductive and chondroprotective effects on cartilage and progenitor cells, and it also emphasizes the possibilities that exist in this research area, especially with regard to the nutritional support of cartilage regeneration and TE, which may not benefit from non-steroidal anti-inflammatory drugs (NSAIDs).

Platelet-rich plasma injections delay the need for knee arthroplasty: a retrospective study and survival analysis

PURPOSE

The biological action of platelet-rich plasma (PRP) could slow down the osteoarthritis progression, resulting in a delay of joint replacement. This work aims to evaluate the ability of PRP to postpone and even avoid knee replacement in patients with knee osteoarthritis (KOA) analyzing, on the one hand, the time of delay and on the other hand the percentage of patients without undergoing total knee arthroplasty (TKA).

METHODS

A retrospective analysis and a survival analysis were conducted. KOA patients who underwent knee replacement between 2014 and 2019 and previously received PRP infiltrations were included in the retrospective analysis. Regarding survival analysis, KOA patients who received PRP treatment during 2014 and with follow-up until 2019 were included. The dates of PRP treatment and TKA, KOA severity, age of the patients, number of PRP cycles, and administration route were analyzed.

RESULTS

This work included 1084 patients of which 667 met the inclusion criteria. 74.1% of the patients in the retrospective study achieved a delay in the TKA of more than 1.5 years, with a median delay of 5.3 years. The survival analysis showed that 85.7% of the patients did not undergo TKA during the five year follow-up. The severity degree, age, PRP cycles, and administration route had a statistically significant influence on the efficacy of PRP in delaying surgery.

CONCLUSION

These data suggest that the application of PRP in KOA patients is a treatment that could delay TKA, although further studies are needed to understand and improve this therapy.

Association of weather factors with the risk of pain exacerbations in people with hip osteoarthritis

Objectives: Our objective was to evaluate the association of weather factors with the risk of pain exacerbations in people with symptomatic hip osteoarthritis (OA). Method: Eligible participants with symptomatic hip OA were instructed to log on to the study website and complete questionnaires every 10 days and additionally whenever they considered they were experiencing a pain exacerbation (case period) during the 90 day follow-up. Pain exacerbation was defined as an increase of two points in pain intensity on an 11-point numeric rating scale (0-10) during the follow-up compared with baseline. Each case period was anchored to four control periods within a 35 day interval using a time-stratified approach. Weather data were obtained for both periods from the publicly available meteorological database of the Australian Bureau of Meteorology. We examined the association of weather factors across 72 h before the index date with the risk of pain exacerbation, using conditional logistic regression. Results: Among 252 participants recruited, 129 participants had at least one episode of pain exacerbation and were included in the analysis. A significant dose-response relationship was found between average daily temperature variation in the prior 72 h and risk of pain exacerbations (p = 0.04 for linear trend). There was no significant association between maximum daily temperature, minimum daily temperature, relative humidity, precipitation, or barometric pressure and hip pain exacerbations. Conclusion: The overall results suggest that only daily temperature variation among different weather factors was associated with hip pain exacerbations in people with symptomatic hip OA.

Disorganization of chondrocyte columns in the growth plate does not aggravate experimental osteoarthritis in mice

Osteoarthritis (OA) is a multifactorial joint disease mainly affecting articular cartilage (AC) with a relevant biomechanical component. During endochondral ossification growth plate (GP) chondrocytes arrange in columns. GPs do not ossify in skeletally mature rodents. In neonatal mice, an altered joint loading induces GP chondrocyte disorganization. We aimed to study whether experimental OA involves GP disorganization in adult mice and to assess if it may have additional detrimental effects on AC damage. Knee OA was induced by destabilization of the medial meniscus (DMM) in wild-type (WT) adult mice, and in Tamoxifen-inducible Ellis-van-Creveld syndrome protein (Evc) knockouts (Evc^cKO), used as a model of GP disorganization due to Hedgehog signalling disruption. Chondrocyte column arrangement was assessed in the tibial GP and expressed as Column Index (CI). Both DMM-operated WT mice and non-operated-Evc^cKO showed a decreased CI, indicating GP chondrocyte column disarrangement, although in the latter, it was not associated to AC damage. The most severe GP chondrocyte disorganization occurred in DMM-Evc^cKO mice, in comparison to the other groups. However, this altered GP structure in DMM-Evc^cKO mice did not exacerbate AC damage. Further studies are needed to confirm the lack of interference of GP alterations on the analysis of AC employing OA mice.

Identification of a potential gene target for osteoarthritis based on bioinformatics analyses

Background

Osteoarthritis (OA) is the most common chronic joint disease worldwide. It is characterized by pain and limited mobility in the affected joints and may even cause disability. Effective clinical options for its prevention and treatment are still unavailable. This study aimed to identify differences in gene signatures between tissue samples from OA and normal knee joints and to explore potential gene targets for OA.

Methods

Five gene datasets, namely GSE55457, GSE55235, GSE12021, GSE10575, and GSE1919, were selected from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified using the R programming software. The functions of these DEGs were analyzed, and a protein–protein interaction (PPI) network was constructed. Subsequently, the most relevant biomarker genes were screened using a receiver operating characteristic (ROC) curve analysis. Finally, the expression of the protein encoded by the core gene PTHLH was evaluated in clinical samples.

Results

Eleven upregulated and 9 downregulated DEGs were shared between the five gene expression datasets. Based on the PPI network and the ROC curves of upregulated genes, PTHLH was identified as the most relevant gene for OA and was selected for further validation. Immunohistochemistry confirmed significantly higher PTHLH expression in OA tissues than in normal tissues. Moreover, similar PTHLH levels were detected in the plasma and knee synovial fluid of OA patients.

Conclusion

The bioinformatics analysis and preliminary experimental verification performed in this study identified PTHLH as a potential target for the treatment of OA.

A mobile MRI field study of the biochemical cartilage reaction of the knee joint during a 4,486 km transcontinental multistage ultra-marathon using T2* mapping

Nearly nothing is known about the consequences of ultra-long-distance running on knee cartilage. In this mobile MRI field study, we analysed the biochemical effects of a 4,486 km transcontinental multistage ultra-marathon on femorotibial joint (FTJ) cartilage. Serial MRI data were acquired from 22 subjects (20 male, 18 finisher) using a 1.5 T MR scanner mounted on a 38-ton trailer, travelling with the participants of the TransEurope FootRace (TEFR) day by day over 64 stages. The statistical analyses focused on intrachondral T2* behaviour during the course of the TEFR as the main outcome variable of interest. T2* mapping (sagittal FLASH T2* weighted gradient echo) is a validated and highly accurate method for quantitative compositional cartilage analysis of specific weightbearing areas of the FTJ. T2* mapping is sensitive to changes in the equilibrium of free intrachondral water, which depends on the content and orientation of collagen and the proteoglycan content in the extracellular cartilage matrix. Within the first 1,100 km, a significant running load-induced T2* increase occurred in all joint regions: 44.0% femoral-lateral, 42.9% tibial-lateral, 34.9% femoral-medial, and 25.1% tibial-medial. Osteochondral lesions showed no relevant changes or new occurrence during the TEFR. The reasons for stopping the race were not associated with knee problems. As no further T2* elevation was found in the second half of the TEFR but a decreasing T2* trend (recovery) was observed after the 3,500 km run, we assume that no further softening of the cartilage occurs with ongoing running burden over ultra-long distances extending 4,500 km. Instead, we assume the ability of the FTJ cartilage matrix to reorganize and adapt to the load.