Intra-articular hyaluronic acid in knee osteoarthritis: clinical data for a product family (ARTHRUM), with comparative meta-analyses.

INTRODUCTION: Viscosupplementation is widely practiced, to reduce pain in osteoarthritis (OA), using intra articular (IA) injections of hyaluronic acid (HA). In Europe, these products are class III medical devices, for which the Medical Device Regulation (MDR) requires clinical assessment, based on specific studies and/or a bibliographical review of equivalent devices. The purpose of this article is to present a comparative review between a family of devices (ARTHRUM, from LCA Pharmaceuticals, Chartres, France) and an extensive group of presumed equivalent IA HA devices or their controls, whose results have been published in Scientific journals. METHODS: To meet the criteria used in most ARTHRUM studies, the Western Ontario and McMaster Universities' index sub-scores were selected for pain (WOMAC A), stiffness (WOMAC B) and function (WOMAC C). The main criterion was the variation of the WOMAC A score from T0 (date of inclusion) to T6 (6 months). The other WOMAC criteria were assessed at T1, T3, T6 and complemented by OMERACT-OARSI rates of responders to the treatment. Fifty articles were selected, containing treatment details on more than 12,000 patients. These were divided into three groups: ARTHRUM, EQUIVALENTS and CONTROLS. To get quantitative comparisons, meta-analyses were performed for each criterion individually. The 95% confidence interval of each difference from baseline, was used to assess the clinical relevance, with reference to a minimum validated in OA literature. Comparisons between groups and tolerance assessment completed the investigation. RESULTS: For the WOMAC A, B and C scores, the full 95% CI was always above the minimal perceptible clinical improvement (MPCI), in the ARTHRUM and EQUIVALENTS groups, but not for all criteria in the CONTROLS group. In the comparisons, both ARTHRUM and EQUIVALENTS groups were significantly better than the CONTROLS group for each criterion. The effect size (ES) on pain, for the ARTHRUM and EQUIVALENTS groups, varied from 0.28 to 0.56 and from 0.23 to 0.27, respectively. Overall, ARTHRUM was estimated always non-inferior to EQUIVALENTS, and sometimes statistically and clinically superior. CONCLUSIONS: The comparison of ARTHRUM clinical studies, with studies selected through bibliographic research, leads to the conclusion that the clinical efficacy of the ARTHRUM medical devices, to reduce pain and improve the function in knee OA, during a six-month period, is at least as great as those of equivalent products. With good tolerance results (lowest rate of adverse events, and none of them serious), the risk benefit ratio favours using viscosupplementation with ARTHRUM.

Acide hyaluronique intra articulaire dans la gonarthrose: une étude long-terme, ouverte, de Phase IV, avec analyse détaillée par stade de Kellgren-Lawrence.

INTRODUCTION: Les injections intra articulaires (IA) d'acide hyaluronique (HA) désignées sous le nom de viscosupplémentation (VS), sont fréquemment utilisées dans le traitement symptomatique de la gonarthrose (OA), une affection ostéo-articulaire chronique douloureuse et handicapante, qui touche une fraction importante de la population âgée. La sévérité de la gonarthrose est en général décrite par la classification en stades radiologiques de Kellgren-Lawrence (KL). La VS a été largement étudiée à travers de nombreux essais cliniques; cependant, les résultats sont rarement analysés en détail, en fonction du stade KL. MÉTHODE: Une étude ouverte importante, portant sur 1 177 patients souffrant de gonarthrose, fut réalisée de 2004 à 2007. Chaque patient a reçu un traitement de VS consistant en 3 injections d'ARTHRUM H 2% (LCA Pharmaceutical, Chartres, France). A l'inclusion, les patients ont été décrits par leur profil démographique, leur indice de masse corporelle (IMC), leur stade KL et leur état clinique selon les sous-scores douleur et fonction de l'indice Western Ontario and McMaster Universities (WOMAC). Les visites de suivi étaient à M3, M6 et M9 (mois) après la VS. Cette large base de données a été entièrement retraitée en 2019, de manière à fournir une analyse séparée par stade KL, et fut complétée par l'évaluation des taux de patients répondeurs (%) au traitement, selon l'Outcome Measures in Rheumatoid Arthritis Clinical Trials & Osteoarthritis Research Society International (OMERACT-OARSI). L'analyse fut menée à la fois sur les populations en intention de traiter (ITT) et per protocole (PP) ayant terminé l'étude. RÉSULTATS: En analyse ITT du critère principal, les variations du sous-score WOMAC A (douleur) depuis l'inclusion jusqu'à la fin de l'étude, ont été respectivement de 19,8 ; 19,8 ; 17,8 et 14,2, sur une échelle de 0-100, pour les patients des stades KL I à KL IV. En analyse PP dans les mêmes conditions, ces variations ont été de 20,6 ; 19,9 ; 17,1 et 11,7. Tous ces résultats étaient significatifs par rapport aux valeurs à l'inclusion (p<0.001) et cliniquement pertinents à chaque stade KL. Des améliorations significatives ont été également observées pour le sous-score WOMAC C (fonction), et pour les autres critères secondaires. Le taux de répondeurs OMERACT-OARSI variait de 72 à 82% pour les patients KL I à III à M6 et M9. Pour les patients KL IV, le maximum atteint a été 47.7% à M6. Les autres paramètres tels que le sexe, l'IMC ou l'âge, ne furent pas identifiés comme des facteurs de pronostic pour la réponse à la VS. CONCLUSIONS: L'analyse détaillée par stade KL d'une large cohorte de patients suivis en ouvert, suggère le traitement de VS avec ARTHRUM H 2% est applicable à une grande variété de patients gonarthrosiques.

The lateral joint space width can be measured reliably with Telos valgus stress radiography in medial knee osteoarthritis.

OBJECTIVE: To examine the reproducibility of valgus stress radiographs with the Telos stress device for assessment of lateral compartment degenerative changes in patients with medial osteoarthritis of the knee. MATERIALS AND METHODS: A prospective reliability study was performed. Seventy-nine patients (80 knees) were included, and standardized valgus stress radiographs were obtained using the Telos stress device. Osteophytes and joint space narrowing (JSN) were graded using the OARSI (Osteoarthritis Research Society International) classification, and the joint space width (JSW) was measured in millimeters. Reproducibility was determined as intra-and inter-rater reliability and test-retest reliability. Weighted kappa was used to determine the reliability of osteophyte and JSN grading, and the intra-class correlation coefficient for JSW. RESULTS: Grading of osteophytes had an intra- and inter-rater reliability ranging from 0.40 to 0.83 on the medial side and ranging from 0.39 to 0.87 on the lateral side. Grading of medial JSN had an intra- and inter-rater reliability ranging from 0.62 to 0.84, and grading of lateral JSN had an intra- and inter-rater reliability ranging from 0.32 to 0.65. Intra- and inter-rater reliability of JSW ranged from 0.84 to 0.98 on the medial side, and from 0.59 to 0.89 on the lateral side. Test-retest reliability of JSW of the medial and lateral side ranged from 0.69 to 0.92. CONCLUSIONS: Standardized valgus stress radiographs taken with the Telos stress device are a reliable supplement in the assessment of medial OA of the knee. Evaluation of the lateral compartment on valgus stress radiographs is most reliable with measurement of the lateral JSW.

Inyección Intraarticular Única de Ácido Hialurónico en la Artrosis de Rodilla: Estudio Multicéntrico Prospectivo Abierto (ART-ONE 75) mediante Comparación Post-Hoc con Placebo.

INTRODUCCIÓN: La viscosuplementación del líquido sinovial mediante la inyección intraarticular (IA) de ácido hialurónico (AH) es un tratamiento sintomático ampliamente utilizado en la artrosis de rodilla (AR). Además de los productos diseñados para realizar inyecciones múltiples (normalmente de 3 a 5 inyecciones, en intervalos de 1 semana), se presta especial atención a los productos de una única inyección, ya que ofrecen ventajas específicas, como son un menor número de visitas al médico y de intervenciones invasivas con sus riesgos asociados. Sin embargo, aún existen dudas sobre la eficacia de estas inyecciones únicas, en comparación con los regímenes de inyecciones múltiples. MÉTODOS: Se realizó un estudio multicéntrico, abierto, prospectivo, post-mercado (ART-ONE 75) con el producto de inyección única ARTHRUM 2,5% (3 ml, 75 mg AH), en 214 pacientes que sufrían de AR. Los pacientes fueron seguidos en D30, D60, D120 y D180 (días). El perfil promedio de los pacientes en el momento de la inclusión fue de 62,9 años, 56% mujeres, grados I-III de Kellgren-Lawrence (46% KL III), IMC de 27,2 kg/m2 y 4 años desde el diagnóstico de AR. Se realizó una comparación post-hoc con una inyección IA única de placebo (326 pacientes, agrupados de 3 estudios ECA), que proporcionaron un perfil de paciente similar. RESULTADOS: el criterio principal fue la variación desde el inicio de la puntuación de la escala WOMAC A (dolor, escala 0-100) en D60, que se redujo en 28,9 (17,4) para la población por intención de tratar (ITT, por sus siglas en inglés) (199 pacientes), 28,0 (17,8) para la población por protocolo (PP) en la inclusión (175 pacientes), y en 27,7 (16,8) para la población PP al finalizar (143 pacientes).Los criterios secundarios y accesorios incluyeron WOMAC A en otras ocasiones, WOMAC B (rigidez), WOMAC C (función), calidad de vida y discapacidad en cada momento de seguimiento. Todos los índices mejoraron significativamente y continuaron mejorando al final del estudio. La evaluación terapéutica en D180 mostró que más del 75% de los pacientes se encontraban satisfechos con la reducción del dolor, la mejora de la movilidad, y la reducción de analgésicos y AINE. El porcentaje de pacientes definidos como respondedores de OMERACT-OARSI fue superior al 86%, a partir de D60 y en adelante. La tolerancia general fue buena, sin que ocurriera ningún evento adverso grave. El resultado de la comparación post-hoc para la escala WOMAC A mostró un tamaño del efecto [IC 95%] desde TE = 0,33 [0,15; 0,51] en D60 a TE = 0,65 [0,45; 0,85] en D180 (p <0,001), frente a la inyección de placebo (solución salina), lo cual es un resultado clínicamente relevante a favor de ARTHRUM 2,5%. CONCLUSIÓN: El presente estudio confirma la eficacia clínica de una única inyección IA de 3 ml de solución de AH conteniendo 75 mg de AH nativo de alto PM (> 2 MDa).

Mono-injection intra-articulaire d'acide hyaluronique dans la gonarthrose : Étude multicentrique prospective ouverte (ART-ONE 75) avec comparaison post hoc versus placebo.

INTRODUCTION: La viscosupplémentation du liquide synovial par injection intra-articulaire d'acide hyaluronique est un traitement symptomatique de l'arthrose, largement utilisé dans la gonarthrose (arthrose du genou). À côté des produits conçus pour être administrés par injections multiples (typiquement 3 à 5 injections à intervalles de 1 semaine), un intérêt particulier se porte sur produits en injection unique (mono-injection) qui offrent des avantages spécifiques tels que la réduction du nombre de visites au médecin et du nombre d'interventions invasives avec leurs risques associés. Il subsiste toutefois une question concernant l'efficacité de ces mono-injections, par rapport aux protocoles à injections multiples. MÉTHODES: Une étude post-commercialisation, prospective, multicentrique, ouverte (ART-ONE 75), a été réalisée avec le produit pour injection unique Arthrum 2,5 % (3 mL, 75 mg d'acide hyaluronique) (LCA Pharmaceutical, Chartres, France), sur 214 patients atteints de gonarthrose. Les patients ont été suivis à 30, 60, 120 et 180 jours. Le profil moyen des patients à l'inclusion était un âge de 62,9 ans, 56 % de femmes, un stade radiologique Kellgren-Lawrence de I à III (46 % KL III), un indice de masse corporelle de 27,2 kg/m2 et une antériorité de 4 ans pour la gonarthrose. Une comparaison post hoc a été réalisée par rapport à une injection intra-articulaire unique de placebo (326 patients regroupés à partir de 3 essais randomisés contrôlés), et présentant un profil similaire de patients. RÉSULTATS: Le critère principal était la variation par rapport à la baseline, de l'indice Western Ontario and McMaster Universities, sous-échelle de la douleur (WOMAC A) dont le score (base 0-100), était réduit à 60 jours, de 28,9 (17,4) pour la population en intention de traiter (199 patients), de 28,0 (17,8) pour la population per protocole à l'inclusion (175 patients), et de 27,7 (16.8) pour la population per protocole ayant terminé l'étude (143 patients). Les critères secondaires et accessoires comprenaient le score WOMAC A aux autres dates, le score WOMAC B (raideur), le score WOMAC C (fonction), la qualité de vie et le handicap à chaque date de suivi. Tous les indices étaient significativement améliorés et continuaient à s'améliorer à la fin de l'étude. L'évaluation thérapeutique à 180 jours a montré que plus de 75 % des patients étaient satisfaits de la réduction de la douleur, de l'amélioration de la mobilité et de la réduction de la consommation d'analgésiques et d'anti-inflammatoires non stéroïdiens. Le pourcentage de patients définis comme répondeurs selon les critères de l'OMERACT-OARSI Initiative était > 86 %, à partir de 60 jours. La tolérance globale était bonne, sans aucun évènement indésirable grave. Les résultats de la comparaison post hoc pour le score WOMAC A ont montré une taille d'effet variant de 0,33 (IC 95 % 0,15-0,51), à 60 jours à 0,65 (IC 95 % 0,45-0,85) à 180 jours (p < 0.001), versus placebo injecté (solution saline), qui est cliniquement significative en faveur d'Arthrum 2,5 %. CONCLUSION: La présente étude suggère l'efficacité clinique d'une mono-injection IA de 3 mL de solution viscoélastique contenant 75 mg d'AH natif de haut poids moléculaire (> 2 MDa).

Radiographically detectable intra-articular mineralization: Predictor of knee osteoarthritis outcomes or only an indicator of aging? A brief report from the osteoarthritis initiative.

Objective: To determine the association between Intra-articular mineralization (IAM) and knee osteoarthritis (OA) outcomes stratified according to participants' age. Methods: Participants from the Osteoarthritis Initiative (OAI) with baseline radiographic OA (i.e., Kellgren-Lawrence grade ≥2 with Osteoarthritis Research Society International (OARSI) atlas joint space narrowing (JSN)) in either knee were identified. Both knees and dominant hand baseline radiographs were evaluated for the presence of IAM. Whole-grade OARSI-JSN radiographic progression and increased Western Ontario and McMaster universities osteoarthritis index scores of the knees with baseline radiographic OA (assessed annually) were defined as radiographic and symptomatic progression, respectively. Cox proportional-hazards and longitudinal multilevel regression models investigated radiographic and symptomatic progression, respectively. Results: 2010 participants with baseline radiographic OA in either one or both knees (N â€‹= â€‹2976) were identified. 178 participants had baseline IAM (hand radiographs â€‹= â€‹46, knee radiographs â€‹= â€‹166, both â€‹= â€‹34). An adjusted logistic regression model suggests an association between age and IAM (Odds Ratio: 1.06, 95% Confidence Interval (CI): 1.04-1.08). Presence of any IAM was not associated with whole-grade OARSI-JSN (Hazard Ratio (HR): 1.00, 95% CI: 0.73-1.37) or symptomatic progression (Estimated difference: 1.24, p-value: 0.13) in all participants. Using stratification analysis, in younger participants <60 years old, presence of any IAM was associated with radiographic progression (HR: 1.90, 95% CI: 1.01-3.60). Conclusion: Although the presence of any radiographic IAM increases with higher age and does not predict knee OA outcomes across the entire sample of OAI participants, it is associated with knee OA radiographic progression in participants aged <60.

A static magnetic field enhances the repair of osteoarthritic cartilage by promoting the migration of stem cells and chondrogenesis.

Objective: To investigate the therapeutic effects of static magnetic field (SMF) and its regulatory mechanism in the repair of osteoarthritic cartilage. Methods: Fourteen-week-old female C57BL/6 mice were randomly divided into the sham operation group and the osteoarthritis (OA) groups with and without SMF application. SMF was applied at 200 â€‹mT for two consecutive weeks. Changes in knee cartilage were examined by histomorphometry, and the chondrogenesis and migration of endogenous stem cells were assessed. The expression of SRY-related protein 9 (SOX9), Collagen type II (COL2), matrix metallopeptidase 13 (MMP13), stromal cell-derived factor 1/C-X-C chemokine receptor type 4 (SDF-1/CXCR4), Piezo1 and other genes was evaluated, and the mechanism of SMF's action was tested using the CXCR4 inhibitor, AMD3100, and Piezo1 siRNA. Results: SMF significantly decreased the OARSI scores after induction of OA. SMF was beneficial to chondrogenesis by elevating SOX9. In the OA mouse model, an increase in MMP13 with a decrease in COL2 led to the destruction of the cartilage extracellular matrix, which was suppressed by SMF. SMF promoted the migration of cartilage-derived stem/progenitor cells and bone marrow-derived mesenchymal stem cells (MSCs). It increased SDF-1 and CXCR4, while the CXCR4 inhibitor significantly suppressed the beneficial effects of SMF. The application of Piezo1 siRNA inhibited the SMF-induced increase of CXCR4. Conclusion: SMF enhanced chondrogenesis and improved cartilage extracellular matrices. It activated the Piezo1-mediated SDF-1/CXCR4 regulatory axis and promoted the migration of endogenous stem cells. Collectively, it attenuated the pathological progression of cartilage destruction in OA mice. The Translational potential of this article: The findings in this study provided convincing evidence that SMF could enhance cartilage repair and improve OA symptoms, suggesting that SMF could have clinical value in the treatment of OA.

Teriparatide ameliorates articular cartilage degradation and aberrant subchondral bone remodeling in DMM mice.

Objective: Knee osteoarthritis (KOA) is a highly prevalent musculoskeletal disorder characterized by degeneration of cartilage and abnormal remodeling of subchondral bone (SCB). Teriparatide (PTH (1-34)) is an effective anabolic drug for osteoporosis (OP) and regulates osteoprotegerin (OPG)/receptor activator of nuclear factor ligand (RANKL)/RANK signaling, which also has a therapeutic effect on KOA by ameliorating cartilage degradation and inhibiting aberrant remodeling of SCB. However, the mechanisms of PTH (1-34) in treating KOA are still uncertain and remain to be explored. Therefore, we compared the effect of PTH (1-34) on the post-traumatic KOA mouse model to explore the potential therapeutic effect and mechanisms. Methods: In vivo study, eight-week-old male mice including wild-type (WT) (n â€‹= â€‹54) and OPG-/- (n â€‹= â€‹54) were investigated and compared. Post-traumatic KOA model was created by destabilization of medial meniscus (DMM). WT mice were randomly assigned into three groups: the sham group (WT-sham; n â€‹= â€‹18), the DMM group (WT-DMM; n â€‹= â€‹18), and the PTH (1-34)-treated group (WT-DMM â€‹+ â€‹PTH (1-34); n â€‹= â€‹18). Similarly, the OPG-/- mice were randomly allocated into three groups as well. The designed mice were executed at the 4th, 8th, and 12th weeks to evaluate KOA progression. To further explore the chondro-protective of PTH (1-34), the ATDC5 chondrocytes were stimulated with different concentrations of PTH (1-34) in vitro. Results: Compared with the WT-sham mice, significant wear of cartilage in terms of reduced cartilage thickness and glycosaminoglycan (GAG) loss was detected in the WT-DMM mice. PTH (1-34) exhibited cartilage-protective by alleviating wear, retaining the thickness and GAG contents. Moreover, the deterioration of the SCB was alleviated and the expression of PTH1R/OPG/RANKL/RANK were found to increase after PTH (1-34) treatment. Among the OPG-/- mice, the cartilage of the DMM mice displayed typical KOA change with higher OARSI score and thinner cartilage. The damage of the cartilage was alleviated but the abnormal remodeling of SCB didn't show any response to the PTH (1-34) treatment. Compared with the WT-DMM mice, the OPG-/--DMM mice caught more aggressive KOA with thinner cartilage, sever cartilage damage, and more abnormal remodeling of SCB. Moreover, both the damaged cartilage from the WT-DMM mice and the OPG-/--DMM mice were alleviated but only the deterioration of SCB in WT-DMM mice was alleviated after the administration of PTH (1-34). In vitro study, PTH (1-34) could promote the viability of chondrocytes, enhance the synthesis of extracellular matrix (ECM) (AGC, COLII, and SOX9) at the mRNA and protein level, but inhibit the secretion of inflammatory cytokines (TNF-α and IL-6). Conclusion: Both wear of the cartilage was alleviated and aberrant remodeling of the SCB was inhibited in the WT mice, but only the cartilage-protective effect was observed in the OPG-/- mice. PTH (1-34) exhibited chondro-protective effect by decelerating cartilage degeneration in vivo as well as by promoting the proliferation and enhancing ECM synthesis of chondrocytes in vitro. The current investigation implied that the rescue of the disturbed SCB is dependent on the regulation of OPG while the chondro-protective effect is independent of modulation of OPG, which provides proof for the treatment of KOA. The translational potential of this article: Systemic administration of PTH (1-34) could exert a therapeutic effect on both cartilage and SCB in different mechanisms to alleviate KOA progression, which might be a novel therapy for KOA.

Do people with knee osteoarthritis use guideline-consistent treatments after an orthopaedic surgeon recommends nonsurgical care? A cross-sectional survey with long-term follow-up.

Objective: Describe "usual care" patterns of education, exercise, weight management, pain medication and other nonsurgical treatments for knee osteoarthritis (OA) in people recommended for nonsurgical care by an orthopaedic surgeon. Methods: We used a telephone-administered questionnaire to capture treatments people with knee OA used over the three to six years after an orthopaedic surgeon recommended nonsurgical care. The primary outcome, guideline-consistent nonsurgical treatments, was an aggregate measure defined as using education, exercise, weight management, and at least one recommended medication. Secondary outcomes were first-line (education, exercise, and weight management) and guideline-inconsistent treatments (orthoses, opioids, hyaluronic acid, platelet rich plasma, and stem cell therapy). Multivariable robust Poisson regression assessed the association between participant characteristics and use of guideline-consistent, first-line and guideline-inconsistent treatments. Results: 479 people were invited and 250 participated (52%). Participants were 58% female with a mean age 66.2 years. Participants received education by a healthcare professional (64%), exercised regularly (74%), used weight management (38%), and used recommended pain medications (91%). All guideline-consistent nonsurgical treatments were used by 19% of participants, 19% of participants used first-line treatments, and 42% used guideline-inconsistent treatments. Over six years, 34% had another consult then underwent arthroplasty. Older participants were less likely to use any treatment. People without post-secondary education were less likely to use first-line treatments (RR 0.54, 95% CI: 0.30-0.96), and females were less likely to use guideline-inconsistent treatments (RR 0.62, 95% CI:0.47-0.81). Conclusions: Nonsurgical usual care for people with knee OA was not consistent with international clinical guidelines.

Interventions for osteoarthritis pain: A systematic review with network meta-analysis of existing Cochrane reviews.

Objective: To conduct a network meta-analysis comparing all treatments for osteoarthritis (OA) pain in the Cochrane Library. Design: The Cochrane Library and Epistemonikos were searched for randomized controlled trials (RCTs) about treatments for hip and knee OA. We constructed 17 broad categories, comprising drug treatments, exercise, surgery, herbs, orthotics, passive treatments, regenerative medicine, diet/weight loss, combined treatments, and controls. In addition to a full network analysis, we compared the direct/indirect effects, and studies with shorter-/longer follow-up. CINeMA software was used for assessing confidence in network meta-analysis estimates. Results: We included 35 systematic reviews including 445 RCTs. There were 153 treatments for OA. In total, 491 comparisons were related to knee OA, less on hip OA, and only nine on hand OA. Six treatment categories showed clinically significant effects favoring treatment over control on pain. "Diet/weight loss" and "Surgery" had effect sizes close to zero. The network as a whole was not coherent. Of 136 treatment comparisons, none were rated as high confidence, six as moderate, 13 as low, and 117 as very low. Conclusions: Direct comparison of different available treatment options for OA is desirable, however not currently feasible in practice, due to heterogeneous study populations and lack of clear descriptions of control interventions. We found that many treatments were effective, but since the network as a whole was not coherent and lacked high confidence in the treatment comparisons, we could not produce a ranking of effects.

Hemodynamic stress shapes subchondral bone in osteoarthritis: An emerging hypothesis.

Osteoarthritis (OA) is no longer regarded as a simple wear-and-tear problem of articular cartilage. Instead, OA is a whole joint disorder involving both cartilaginous and non-cartilaginous tissues such as subchondral bone and synovium. Among them, subchondral bone undergoes constant remodeling in response to the changes of mechanical environment. Current understanding of subchondral bone disturbance in OA is limited to its link with an altered local mechanical loading as a result of ligament or meniscus injury. Very recently, hypertension, the most common vascular morbidity, has been emerged as an independent risk factor of OA. It might suggest a plausible role of systemic hemodynamic mechanical stress in subchondral bone remodeling and the pathogenesis of OA. However, their relationship remains not fully understood. Based on our preliminary clinical observation on the association of hemodynamic parameters with subchondral bone mass and microstructure in late-stage knee OA patients, we formulate a vascular etiology hypothesis of OA from a mechanobiology perspective. Noteworthily, hemodynamic stress associated with subchondral bone mineral density; yet compressive mechanical loading does not. Furthermore, hemodynamic parameters positively correlated with subchondral plate-like trabecular bone volume but negatively associated with rod-like trabecular bone volume. In contrast, compressive mechanical loading tends to increase both plate-like and rod-like trabecular bone volume. Taken together, it warrants further investigations into the distinct role of hemodynamic or compressive stress in shaping subchondral bone in the pathophysiology of OA. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: This work provides a new insight, from the angle of biomechanics, into the emerging role of vascular pathologies, such as hypertension, in the pathogenesis of OA. It might open up a new avenue for the development of a mechanism-based discovery of novel diagnostics and therapeutics.

Exploring the translational potential of clusterin as a biomarker of early osteoarthritis.

BACKGROUND: Clusterin (CLU; also known as apolipoprotein J) is an ATP-independent holdase chaperone that prevents proteotoxicity as a consequence of protein aggregation. It is a ∼60 kDa disulfide-linked heterodimeric protein involved in the clearance of cellular debris and the regulation of apoptosis. CLU has been proposed to protect cells from cytolysis by complement components and has been implicated in Alzheimer's disease due to its ability to bind amyloid-ß peptides and prevent aggregate formation in the brain. Recent studies suggest that CLU performs moonlighting functions. CLU exists in two major forms: an intracellular form and a secreted extracellular form. The intracellular form of CLU may suppress stress-induced apoptosis by forming complexes with misfolded proteins and facilitates their degradation. The secreted form of CLU functions as an extracellular chaperone that prevents protein aggregation. METHODS: In this review, we discuss the published literature on the biology of CLU in cartilage, chondrocytes, and other synovial joint tissues. We also review clinical studies that have examined the potential for using this protein as a biomarker in synovial and systemic fluids of patients with rheumatoid arthritis (RA) or osteoarthritis (OA). RESULTS: Since CLU functions as an extracellular chaperone, we propose that it may be involved in cytoprotective functions in osteoarticular tissues. The secreted form of CLU can be measured in synovial and systemic fluids and may have translational potential as a biomarker of early repair responses in OA. CONCLUSION: There is significant potential for investigating synovial and systemic CLU as biomarkers of OA. Future translational and clinical orthopaedic studies should carefully consider the diverse roles of this protein and its involvement in other comorbidities. Therefore, future biomarker studies should not correlate circulating CLU levels exclusively to the process of OA pathogenesis and progression. Special attention should be paid to CLU levels in synovial fluid. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: There is significant potential for investigating synovial and systemic CLU as a predictive biomarker of osteoarthritis (OA) progression and response to novel treatments and interventions. Given that CLU plays diverse roles in other comorbidities such as rheumatoid arthritis (RA) and obesity, future translational and clinical orthopaedic biomarker studies should not directly correlate circulating CLU levels to the process of OA pathogenesis and progression. However, special attention should be paid to CLU levels in synovial fluid. The cytoprotective properties of CLU may support the implementation of regenerative strategies and new approaches for developing targeted therapeutics for OA.

Quercitrin alleviates cartilage extracellular matrix degradation and delays ACLT rat osteoarthritis development: An in vivo and in vitro study.

Introduction: Disruptions of extracellular matrix (ECM) degradation homeostasis play a significant role in the pathogenesis of osteoarthritis (OA). Matrix metalloproteinase 13 (MMP13) and collagen Ⅱ are important components of ECM. Earlier we found that quercitrin could significantly decrease MMP13 gene expression and increase collagen Ⅱ gene expression in IL-1ß-induced rat chondrocytes and human chondrosarcoma (SW1353) cells. Objectives: The effects and mechanism of quercitrin on OA were explored. Methods: Molecular mechanisms of quercitrin on OA were studied in vitro in primary chondrocytes and SW1353 cells. An anterior cruciate ligament transection (ACLT) rat model of OA was used to investigate the effect of quercitrin in vivo. Micro-CT analysis and Safranin O-Fast Green Staining of knee joint samples were performed to observe the damage degree of tibial subchondral bone. Immunohistochemistry of knee joint samples were conducted to observe the protein level of MMP13, collagen Ⅱ and p110α in articular cartilage. Results: In vitro, quercitrin promoted cell proliferation and delayed ECM degradation by regulating MMP13 and collagen II gene and protein expressions. Moreover, quercitrin activated the Phosphatidylinositol 3-kinase p110α (p110α)/AKT/mTOR signaling pathway by targeting p110α. We also firstly showed that the gene expression level of p110α was remarkably decreased in cartilage of OA patients. The results showed that intra-articular injection of quercitrin increased bone volume/tissue volume of tibial subchondral bone and cartilage thickness and reduced the Osteoarthritis Research Society International scores in OA rats. Meanwhile, immunohistochemical results showed that quercitrin exerted anti-OA effect by delaying ECM degradation. Conclusion: These findings suggested that quercitrin may be a prospective disease-modifying OA drug for prevention and treatment of early stage OA.

Prevalence of patellofemoral joint osteoarthritis after anterior cruciate ligament injury and associated risk factors: A systematic review.

BACKGROUND: The prevalence of patellofemoral joint (PFJ) osteoarthritis (OA) after anterior cruciate ligament (ACL) injury was inconsistently reported in the literature. This review summarises the reported prevalence of PFJ OA and risk factors of PFJ OA after ACL injury. METHODS: PubMed, Embase, WoS, and MEDLINE (OVID) were searched up to 1 March 2019. A modified version of the Coleman methodology score was used to assess the methodological quality of the included studies. Prevalence of PFJ OA was pooled depended on different interventions in ACL injured populations. RESULTS: Thirty-eight studies were included. Five different radiographic classification methods were used: the Kellgren and Lawrence Grade 2, IKDC Grade B, Fairbank Grade 1, joint space narrowing of Grade 2 based on OARSI, and Ahlbäck Grade 1. One included study used MRI Osteoarthritis Knee Score to evaluate PFJ degenerative changes. The overall prevalence of PFJ OA after ACL injury in included studies varied between 4.5% and 80%. The large variation of PFJ OA prevalence is mainly because of different follow-up period and surgical techniques. The pooled data showed that bone-patellar tendon-bone graft, single-bundle ACL reconstruction (ACLR), and delayed ACLR are likely associated with PFJ degenerative changes after ACL injury. ACLR, delayed ACLR, body mass index (BMI), meniscectomy, patellofemoral chondral lesions, age at surgery, and TFJ OA were identified in the literature inducing PFJ OA after ACL injury. CONCLUSIONS: Large variations of PFJ OA after ACL injury are associated with different follow-up period and surgical techniques. ACL reconstructed population with bone-patellar tendon-bone graft, single-bundle reconstruction, and delayed operation time has a high prevalence of PFJ OA. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: This review focuses more on the effect of surgical technique factors on the degenerative changes on PFJ. The results reveal that BPTB, single-bundle reconstruction, and delayed ACLR are more likely associated with PFJ degenerative changes after ACL injury. These findings imply that awareness of PFJ problems after surgical intervention will remind of surgeons taking PFJ into consideration in operations, which is likely to reduce the incidences of anterior knee pain, patellar maltracking, and over-constrained patella in the early stage after surgery.

Developing prediction models for total knee replacement surgery in patients with osteoarthritis: Statistical analysis plan.

Background: Approximately 12-20% of those with osteoarthritis (OA) in Australia who undergo total knee replacement (TKR) surgery do not report any clinical improvement. There is a need to develop prediction tools for use in general practice that allow early identification of patients likely to undergo TKR and those unlikely to benefit from the surgery. First-line treatment strategies can then be implemented and optimised to delay or prevent the need for TKR. The identification of potential non-responders to TKR may provide the opportunity for new treatment strategies to be developed and help ensure surgery is reserved for those most likely to benefit. This statistical analysis plan (SAP) details the statistical methodology used to develop such prediction tools. Objective: To describe in detail the statistical methods used to develop and validate prediction models for TKR surgery in Australian patients with OA for use in general practice. Methods: This SAP contains a brief justification for the need for prediction models for TKR surgery in general practice. A description of the data sources that will be linked and used to develop the models, and estimated sample sizes is provided. The planned methodologies for candidate predictor selection, model development, measuring model performance and internal model validation are described in detail. Intended table layouts for presentation of model results are provided. Conclusion: Consistent with best practice guidelines, the statistical methodologies outlined in this SAP have been pre-specified prior to data pre-processing and model development.

Kinsenoside attenuates osteoarthritis by repolarizing macrophages through inactivating NF-κB/MAPK signaling and protecting chondrocytes.

The objective was to investigate the effect of kinsenoside (Kin) treatments on macrophage polarity and evaluate the resulting protection of chondrocytes to attenuate osteoarthritis (OA) progression. RAW264.7 macrophages were polarized to M1/M2 subtypes then administered with different concentrations of Kin. The polarization transitions were evaluated with quantitative real-time polymerase chain reaction (qRT-PCR), confocal observation and flow cytometry analysis. The mechanism of Kin repolarizing M1 macrophages was evaluated by Western blot. Further, macrophage conditioned medium (CM) and IL-1ß were administered to chondrocytes. Micro-CT scanning and histological observations were conducted in vivo on anterior cruciate ligament transection (ACLT) mice with or without Kin treatment. We found that Kin repolarized M1 macrophages to the M2 phenotype. Mechanistically, Kin inhibited the phosphorylation of IκBα, which further reduced the downstream phosphorylation of P65 in nuclear factor-κB (NF-κB) signaling. Moreover, Kin inhibited mitogen-activated protein kinases (MAPK) signaling molecules p-JNK, p-ERK and p-P38. Additionally, Kin attenuated macrophage CM and IL-1ß-induced chondrocyte damage. In vivo, Kin reduced the infiltration of M1 macrophages, promoted M2 macrophages in the synovium, inhibited subchondral bone destruction and reduced articular cartilage damage induced by ACLT. All the results indicated that Kin is an effective therapeutic candidate for OA treatment.

Cartilage repair and inhibition of the progression of cartilage degeneration after transplantation of allogeneic chondrocyte sheets in a nontraumatic early arthritis model.

INTRODUCTION: Using a rat model of nontraumatic early arthritis induced by intra-articular administration of low-dose monoiodoacetic acid (MIA), we transplanted allogeneic chondrocyte sheets and examined the effects on tissue repair. METHODS: MIA (0.2 mg/50 µl) was injected into the right knee of 20 male Wistar rats. Four weeks later, rats were randomly allocated into three groups: Group A was examined 4 weeks after administration of MIA; Group B, 8 weeks after MIA injection and chondrocyte sheet transplantation, and Group C, 8 weeks after MIA injection but without chondrocyte sheet transplantation. Allogeneic chondrocyte sheets were transplanted into the right knee of Group B rats. Pain was assessed as the weight distribution ratio of the damaged to undamaged limb. The OARSI score was used for histological scoring. RESULTS: The limb weight distribution ratio indicated significantly less pain in Group B. Histological scoring showed significant differences in cartilage repair and inhibition of the progression of cartilage degeneration between Groups B and C, but not between Groups A and B, or Groups A and C. CONCLUSIONS: These findings suggest that, in this rat model of nontraumatic early arthritis induced by low-dose MIA injection, allogeneic chondrocyte sheet transplantation induces cartilage repair and suppresses cartilage degeneration.