The Effect of Intra-articular Corticosteroids on Articular Cartilage: A Systematic Review

Ultrasound-guided interventions in elite soccer players

In the world of elite soccer, or football as we call it in the UK, a player who cannot play for any length of time costs the team money and team performance. The time to return to play (RTP) is crucial in any player's career, and the use of ultrasound-guided ultrasound injections has become important in the management of injury. In this article, I will explain the importance of good practice when performing these procedures and the use of steroids, sodium hyaluronic acid, platelet-rich plasma (PRP), and other therapies in achieving the goal of decreasing the time of RTP for the footballer. KEY POINTS: •Injection therapies are routine practice in maintaining and treating soccer injuries. •Injection therapies can be safely performed under ultrasound guidance.

Long-term effectiveness of intra-articular injectables in patients with knee osteoarthritis: a systematic review and Bayesian network meta-analysis

BACKGROUND

Intra-articular injectables are proposed as a solution for pain relief and functional improvement in knee osteoarthritis (OA), however most studies involving intra-articular knee injectables are focused on short-term relief, leaving the recommendations regarding long-term management unclear. This network meta-analysis aimed to evaluate the mid- to long-term effectiveness of intra-articular knee injection of platelet-rich plasma (PRP), hyaluronic acid (HA), corticosteroids (CS), and their combinations for management of knee OA.

METHODS

Relevant studies were searched through PubMed, EMBASE, Scopus, and Cochrane Register of Trials databases from inception to 20th October, 2024 for randomized controlled trials (RCTs) of knee OA patients who had taken intra-articular injectable treatment with a follow-up duration of at least one year. The study included 37 RCTs involving 5089 patients. The outcomes assessed were pain relief and functional improvement of knee joint. The random effects Bayesian model was carried out for network meta-analysis. The surface under the cumulative ranking (SUCRA) curve demonstrated the rank probability of each injectable therapy for different outcomes.

RESULTS

Analysis revealed that, in terms of both knee pain relief and improvement of functional outcomes, the combined intra-articular injection of PRP and HA was ranked ahead of the isolated administration of PRP, followed by combination of HA with CS, HA alone, placebo, and CS at the end of one year.

CONCLUSION

These findings emphasize the sustained efficacy of PRP, particularly when combined with HA, in providing superior long-term pain relief and functional improvement in knee OA compared to other intra-articular injectables, highlighting its potential as a preferred treatment modality.

The Anti-Inflammatory Effects of Liraglutide in Equine Inflammatory Joint Models

This study investigates the anti-inflammatory properties of liraglutide, a glucagon-like peptide 1 receptor agonists, in equine in vitro models and in an in vivo acute synovitis model in Shetland ponies. The anti-inflammatory effect of liraglutide was assessed by measuring concentrations of inflammatory biomarker C-C Motif Chemokine Ligand 2 (CCL2) in culture media of equine whole blood, peripheral blood mononuclear cells (PBMCs), chondrocytes, and synoviocytes, with or without lipopolysaccharide (LPS) or interleukin-1β. In the in vivo experiment, acute synovitis was bilaterally induced with 0.25 ng LPS in the intercarpal joints of seven healthy Shetland ponies. The ponies were subsequently treated with either 6 mg liraglutide or a placebo as a paired control in each joint. The impact of liraglutide on biomarkers associated with inflammation (including white blood cell count, total protein, CCL2, and bradykinin) and cartilage metabolism (such as glycosaminoglycans, general matrix metalloproteinase activity, carboxypropeptide type II collagen, and collagen-cleavage neoepitope of type II collagen) was assessed across serial synovial fluid samples. Liraglutide was found to have an anti-inflammatory effect by reducing CCL2 concentrations in culture media of whole blood, PBMCs, chondrocytes, and synoviocytes. In contrast, no significant differences in synovial fluid inflammatory nor cartilage metabolism biomarker levels were found between joints treated with LPS and 6 mg liraglutide, versus LPS and placebo. In conclusion, liraglutide demonstrates the potential to attenuate inflammatory processes in joint cells. Additional research is necessary to validate its efficacy within the complex milieu of an inflamed joint.

Advances and Challenges in the Pursuit of Disease-Modifying Osteoarthritis Drugs: A Review of 2010-2024 Clinical Trials

Background/Objectives: Osteoarthritis (OA) is a highly prevalent, degenerative joint disease capable of causing severe pain and impaired mobility. Current treatments mitigate symptoms but do not cure the disease. The development of a disease-modifying osteoarthritis drug (DMOAD) could improve patient outcomes by slowing, halting, or reversing joint damage. Many DMOADs have progressed to clinical trials, but very few have made a significant impact, and none have been approved for clinical use. The purpose of this review is to present an update on the current status of DMOADs with a particular focus on results published since 2010. Methods: A comprehensive search was conducted within PubMed and ClinicalTrials.gov for novel DMOADs enrolled in phase II and III clinical trials between 1 January 2010 and 1 July 2024. Results: Eleven DMOAD candidates are reviewed and critically analyzed for their potential benefit in OA treatment-Lorecivivint (SM04690), TissueGene-C, Cindunistat (SD-6010), Sprifermin, UBX0101, TPX-100, GLPG1972/S201086, Lutikizumab (ABT-981), SAR113945, MIV-711, and LNA043-and relevant challenges to their development are discussed. Conclusions: Six DMOADs have demonstrated statistically significant evidence of a structural or symptomatic benefit without major safety concerns in phase II and III randomized controlled trials post-2010.

Structured Polymers Enable the Sustained Delivery of Glucocorticoids within the Intra-Articular Space

Intra-articular glucocorticoid injections are effective in controlling inflammation and pain in arthritides but restricted by short duration of action and risk of joint degeneration. Controlled drug release using biocompatible hydrogels offers a unique solution, but limitations of in situ gelation restrict their application. Gellan sheared hydrogels (GSHs) retain the advantages of hydrogels, however their unique microstructures lend themselves to intra-articular application - capable of shear thinning under force but restructuring at rest to enhance residence. This study examined GSHs for extended intra-articular glucocorticoid delivery of prednisolone (10 mg mL-1); demonstrating links between material mechanics, steroid release, and preclinical assessment of efficacy in synoviocyte culture and transgenic(TNF)197Gkl (TNFtg) murine model of arthritis. GSHs demonstrated sustained release, with typical Fickian profiles over 18 days. Moreover, systems showed good stability under extended culture, with inherent cell-compatibility and suppression of inflammatory synoviocyte activation. In TNFtg animals, GSHs suppressed synovitis (70.08%, p < 0.05), pannus formation (45.01%, p < 0.05), and increased articular cartilage (82.23%, p < 0.05) relative to vehicle controls. The extended profile of steroid release from injectable GSH formulations holds promise in the treatment and management of inflammatory arthritides such as rheumatoid and osteoarthritis, representing a step-change in intra-articular drug delivery to suppress long-term joint inflammation.

9. Chronic knee pain

INTRODUCTION

Chronic knee pain is defined as pain that persists or recurs over 3 months. The most common is degenerative osteoarthritis (OA). This review represents a comprehensive description of the pathology, diagnosis, and treatment of OA of the knee.

METHODS

The literature on the diagnosis and treatment of chronic knee pain was retrieved and summarized. A modified Delphi approach was used to formulate recommendations on interventional treatments.

RESULTS

Patients with knee OA commonly present with insidious, chronic knee pain that gradually worsens. Pain caused by knee OA is predominantly nociceptive pain, with occasional nociplastic and infrequent neuropathic characteristics occurring in a diseased knee. A standard musculoskeletal and neurological examination is required for the diagnosis of knee OA. Although typical clinical OA findings are sufficient for diagnosis, medical imaging may be performed to improve specificity. The differential diagnosis should exclude other causes of knee pain including bone and joint disorders such as rheumatoid arthritis, spondylo- and other arthropathies, and infections. When conservative treatment fails, intra-articular injections of corticosteroids and radiofrequency (conventional and cooled) of the genicular nerves have been shown to be effective. Hyaluronic acid infiltrations are conditionally recommended. Platelet-rich plasma infiltrations, chemical ablation of genicular nerves, and neurostimulation have, at the moment, not enough evidence and can be considered in a study setting. The decision to perform joint-preserving and joint-replacement options should be made multidisciplinary.

CONCLUSIONS

When conservative measures fail to provide satisfactory pain relief, a multidisciplinary approach is recommended including psychological therapy, integrative treatments, and procedural options such as intra-articular injections, radiofrequency ablation, and surgery.

The paradigm of stem cell secretome in tissue repair and regeneration: Present and future perspectives

As the number of patients requiring organ transplants continues to rise exponentially, there is a dire need for therapeutics, with repair and regenerative properties, to assist in alleviating this medical crisis. Over the past decade, there has been a shift from conventional stem cell treatments towards the use of the secretome, the protein and factor secretions from cells. These components may possess novel druggable targets and hold the key to profoundly altering the field of regenerative medicine. Despite the progress in this field, clinical translation of secretome-containing products is limited by several challenges including but not limited to ensuring batch-to-batch consistency, the prevention of further heterogeneity, production of sufficient secretome quantities, product registration, good manufacturing practice protocols and the pharmacokinetic/pharmacodynamic profiles of all the components. Despite this, the secretome may hold the key to unlocking the regenerative blockage scientists have encountered for years. This review critically analyses the secretome derived from different cell sources and used in several tissues for tissue regeneration. Furthermore, it provides an overview of the current delivery strategies and the future perspectives for the secretome as a potential therapeutic. The success and possible shortcomings of the secretome are evaluated.

Avascular necrosis or rapid destruction of the hip following hip intra-articular corticosteroid injections: a systematic review

PURPOSE

This study aimed to systematically review the literature to identify the incidence of avascular necrosis (AVN) following hip intra-articular corticosteroid injections (IACSIs) as well as to elucidate risk factors that may predispose patients to AVN following IACSI.

METHODS

The MEDLINE, Embase, PubMed, and Web of Science databases were systematically searched through inception to July 21, 2024, in accordance with the PRISMA statement with data extracted for descriptive analysis. The inclusion criteria were hip IACSI and AVN of the femoral head. AVN identified solely prior to IACSI, animal studies, in vitro studies, and studies on paediatric populations were excluded.

RESULTS

A total of 3,652 studies were identified and screened resulting in a total of 14 studies that met the inclusion criteria. Seven were case reports, four were retrospective case-series, and three were retrospective cohort studies. The incidence of femoral head AVN following IACSI ranged from 0.6 to 20.4%. Kelly et al. reported that patient-related factors associated with increased rate of AVN included elevated BMI (p = 0.025), history of cancer therapy (p = 0.012), low serum Vitamin D (p = 0.030), and multiple injections (p = 0.004).

CONCLUSION

In the present literature, the incidence of AVN after hip IACSI ranges from 0.6 to 20.4% with mean follow-up times ranging from 5.4 to 25.3 months. Further randomized controlled trials are necessary to elucidate if there is a causative relationship between hip IACSI and AVN.

The Combined Use of Triamcinolone and Platelet-Rich Plasma in Equine Metacarpophalangeal Joint Osteoarthritis Treatments: An In Vivo and In Vitro Study

Intra-articular corticosteroids, such as triamcinolone acetonide (TA), help reduce pain related to osteoarthritis (OA), but they may impair cartilage metabolism. In contrast, platelet-rich plasma (PRP) therapy, a regenerative therapy, has shown potential to promote healing and regeneration of articular cartilage. This study investigates the effects of combining PRP with TA to treat osteoarthritis in racehorses. The study proposes that PRP injection following TA treatment could reduce side effects and improve treatment outcomes. Firstly, in the in vitro study, chondrocytes were exposed to different TA concentrations, with or without PRP. TA dramatically reduced chondrocyte viability. However, this was prevented by the addition of PRP, which also increased cell proliferation. In the in vivo study, 32 racehorses with metacarpophalangeal (MCP) joint OA were separated into two groups: one received only TA, while the other received TA followed by PRP. For both groups, there were improved flexion assessments one week following the last treatment, but by two weeks following the last treatment, only TA+PRP had improved flexion assessments. TA+PRP also had improved lameness scores two weeks after the last treatment. In conclusion, combining PRP with TA could enhance chondrocyte viability and provide a better long-term therapeutic option for treating OA in racehorses. Further trials are required to thoroughly assess this technique's safety and efficacy.

Genicular Artery Embolization for Treatment of Symptomatic Knee Osteoarthritis: 2-Year Outcomes from a Prospective IDE Trial

PURPOSE

To report the 24-month outcomes and subgroup analysis evaluating the safety and effectiveness of the genicular artery embolization (GAE) for the treatment of symptomatic knee osteoarthritis (OA).

MATERIALS AND METHODS

Forty participants with symptomatic moderate-to-severe knee OA from a single-center, single-arm, prospective investigational device exemption trial of GAE were included in this study. Abnormal genicular artery neovascularity was identified at the subject's focal knee pain with digital subtraction angiography and cone-beam computed tomography (CT). Embolization was performed with 100-μm microspheres. The primary end point was treatment effectiveness as measured by sustained improvement in OA symptoms at 24 months, quantified using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Treatment success was defined as ≥50% decrease in WOMAC relative to baseline. Clinical outcomes were assessed with mean age of 66.0 years (SD ± 8.1) and body mass index of 30.1 kg/m2 (SD ± 6.2).

RESULTS

Of the 40 patients, 2 (5.0%) were lost to follow-up. Overall, 18 of 38 (47.4%) patients demonstrated ≥50% reduction in WOMAC at 24 months. In the subset of patients with initial clinical success at 12 months, 18 of 25 (72.0%) reported sustained clinical success at 24 months. Seven of 25 (28.0%) patients had symptom recurrence between 12 and 24 months and were determined to be clinical failures. All treatment-related adverse events occurred within 12 months after GAE, without additional events after 12 months.

CONCLUSIONS

GAE is effective in achieving sustained symptom relief related to moderate-to-severe knee OA for up to 24 months with an acceptable safety profile.

Platelet-Rich Plasma Versus Corticosteroid Injections for Chronic Tendinopathies: A Systematic Review and Meta-Analysis

Chronic tendinopathy is a degenerative condition characterized by persistent pain, functional limitations, and tendon thickening, often resulting from repetitive overuse or failed tendon healing. Left untreated, it can progress to tendon rupture, prolonged disability, and impaired quality of life. Management typically includes conservative therapies, such as physical therapy, corticosteroid (CS) injections for short-term relief, and platelet-rich plasma (PRP) as a regenerative therapy with potential long-term benefits. This systematic review and meta-analysis evaluates and compares the effectiveness of PRP and CS injections for chronic tendinopathies regarding pain reduction, functional improvement, and long-term outcomes. A structured search of PubMed, Scopus, Google Scholar, and the Cochrane Library identified randomized controlled trials (RCTs) and comparative studies. Primary outcomes included pain reduction and functional improvement while secondary outcomes assessed heterogeneity and publication bias. PRP and CS injections demonstrated no significant difference in short-term pain reduction. Functional outcomes were comparable in the short term but showed a trend favoring PRP at longer follow-up periods. PRP exhibited a slight advantage in long-term functional recovery, though the results were not statistically significant. Substantial heterogeneity across studies highlights the need for standardized protocols and larger trials to confirm these findings and optimize treatment strategies.

The Challenges of Local Intra-Articular Therapy

Fibroblast-like synoviocytes (FLSs) are among the main disease-driving players in most cases of monoarthritis (MonoA), oligoarthritis, and polyarthritis. In this review, we look at the characteristics and therapeutic challenges at the onset of arthritis and during follow-up management. In some cases, these forms of arthritis develop into autoimmune polyarthritis, such as rheumatoid arthritis (RA), whereas local eradication of the RA synovium could still be combined with systemic treatment using immunosuppressive agents. Currently, the outcomes of local synovectomies are well studied; however, there is still a lack of a comprehensive analysis of current local intra-articular treatments highlighting their advantages and disadvantages. Therefore, the aim of this study is to review local intra-articular therapy strategies. According to publications from the last decade on clinical studies focused on intra-articular treatment with anti-inflammatory molecules, a range of novel slow-acting forms of steroidal drugs for the local treatment of synovitis have been investigated. As pain is an essential symptom, caused by both inflammation and cartilage damage, various molecules acting on pain receptors are being investigated in clinical trials as potential targets for local intra-articular treatment. We also overview the new targets for local treatment, including surface markers and intracellular proteins, non-coding ribonucleic acids (RNAs), etc.

Boosting chondrocyte bioactivity with ultra-sulfated glycopeptide supramolecular polymers

Although autologous chondrocyte transplantation can be effective in articular cartilage repair, negative side effects limit the utility of the treatment, such as long recovery times, poor engraftment or chondrogenic dedifferentiation, and cell leakage. Peptide-based supramolecular polymers have emerged as promising bioactive systems to promote tissue regeneration through cell signaling and dynamic behavior. We report here on the development of a series of glycopeptide amphiphile supramolecular nanofibers with chondrogenic bioactivity. These supramolecular polymers were found to have the ability to boost TGFβ-1 signaling by displaying galactosamine moieties with differing degrees of sulfation on their surfaces. We were also able to encapsulate chondrocytes with these nanostructures as single cells without affecting viability and proliferation. Among the monomers tested, assemblies of trisulfated glycopeptides led to elevated expression of chondrogenic markers relative to those with lower degrees of sulfation that mimic chondroitin sulfate repeating units. We hypothesize the enhanced bioactivity is rooted in specific interactions of the supramolecular assemblies with TGFβ-1 and its consequence on cell signaling, which may involve elevated levels of supramolecular motion as a result of high charge in trisulfated glycopeptide amphiphiles. Our findings suggest that supramolecular polymers formed by the ultra-sulfated glycopeptide amphiphiles could provide better outcomes in chondrocyte transplantation therapies for cartilage regeneration. STATEMENT OF SIGNIFICANCE: This study prepares glycopeptide amphiphiles conjugated at their termini with chondroitin sulfate mimetic residues with varying degrees of sulfation that self-assemble into supramolecular nanofibers in aqueous solution. These supramolecular polymers encapsulate chondrocytes as single cells through intimate contact with cell surface structures, forming artificial matrix that can localize the growth factor TGFβ-1 in the intercellular environment. A high degree of sulfation on the glycopeptide amphiphile is found to be critical in elevating chondrogenic cellular responses that supersede the efficacy of natural chondroitin sulfate. This work demonstrates that supramolecular assembly of a unique molecular structure designed to mimic chondroitin sulfate successfully boosts chondrocyte bioactivity by single cell encapsulation, suggesting a new avenue implementing chondrocyte transplantation with supramolecular nanomaterials for cartilage regeneration.

Triamcinolone acetonide has minimal effect on short- and long-term metabolic activities of cartilage

Intra-articular corticosteroid injections, such as triamcinolone acetonide (TA), are commonly used by clinicians to manage joint synovial inflammation. However, due to conflicting evidence in literature, there is a fear among clinicians that the injections may be harmful to otherwise healthy cartilage in young patients. The purpose of this study was to evaluate the effects of TA on young, healthy chondrocytes. Articular cartilage samples were harvested from bovine knee joints (1-2 months old). In both healthy and inflammatory (interleukin-1β) challenged cartilage, samples were treated with TA at doses ranging from 1 nM to 200 μM. Following a short- (2 days) or long-term (10-14 days) treatment, chondrocyte viability, proliferation, and extracellular matrix (ECM) synthesis and degradation were evaluated with a click chemistry-based technique. Chondrocyte viability, proliferation, and anabolic activity were all minimally affected by short-term and long-term TA treatment. After both acute and sustained inflammatory challenges, TA reduced the catabolic activities in cartilage, reducing nascent glycosaminoglycan loss and maintaining cartilage mechanical properties. Overall, at physiologically relevant doses, TA had minimal negative impact on chondrocytes when maintained within their native ECM. Clinical significance: The findings provide new insight for current clinical practices concerning the use of TA in intra-articular injections, especially in young patients, and established a foundation for future investigations into the impact of corticosteroids on joint homeostasis.

Corticosteroid injections for the treatment of osteoarthritis present a wide spectrum of effects ranging from detrimental to disease-modifying: A systematic review of preclinical evidence by the ESSKA Orthobiologic Initiative

PURPOSE

Aim of this systematic review of preclinical evidence was to determine the effects of intra-articular corticosteroid (CS) injections in joints affected by osteoarthritis (OA).

METHODS

A systematic review was performed on animal studies evaluating intra-articular CS injections for OA joints. The search was performed on PubMed, Cochrane, and Web of Science databases. A synthesis of the results was performed investigating CS effects by evaluating studies comparing CS with control groups. Morphological, histological, immunohistochemistry evaluations, clinical outcomes, biomarkers and imaging results were evaluated. The risk of bias was assessed according to the Systematic Review Centre for Laboratory Animal Experimentation's tool.

RESULTS

Thirty-two articles analysing CS effects in OA animal models were included (1079 joints), 18 studies on small and 14 on large animals. CS injections showed overall positive effects in at least one of the outcomes in 68% of the studies, while 16% reported a deleterious effect. CS improved cartilage and synovial outcomes in 68% and 60% of the studies, but detrimental effects were documented in 11% and 20% of the studies, respectively. Clinical parameters evaluated in terms of pain, lameness or joint swelling improved in 63% of the studies but deteriorated in 13%. Evidence is limited on imaging and biomarkers results, as well as on the best CS type, dose, formulation and injection protocol. The risk of bias assessment revealed a 28% low and an 18% high risk of bias.

CONCLUSION

Intra-articular CS injections induced a wide range of results on OA joints in experimental animal models, from disease-modifying and positive effects on pain and joint function at short-term evaluation to the lack of benefit or even negative effects. This underlines the need to identify more specific indications and treatment modalities to avoid possible detrimental effects while maximising the anti-inflammatory properties and the benefits of intra-articular CS in OA joints.

LEVEL OF EVIDENCE

Level II.

Outcomes Following Autologous Osteochondral Transplantation for Osteochondral Lesions of the Talus at 10-Year Follow-Up: A Retrospective Review

OBJECTIVE

The purpose of this study was to evaluate outcomes following autologous osteochondral transplantation (AOT) for the treatment of osteochondral lesions of the talus (OLT) at a minimum of 10-year follow-up.

DESIGN

Retrospective chart review identified patients who underwent AOT for the treatment of OLT. Pre-operative magnetic resonance imaging (MRI) scans were obtained in all patients. Clinical outcomes assessed included: pre- and post-operative foot and ankle outcome score (FAOS), visual analog scale (VAS), patient satisfaction, complications, failures and secondary surgical procedures.

RESULTS

Thirty-nine patients with a mean lesion size was 122.3 ± 64.1 mm2 and mean follow-up time of 138.9 ± 16.9 months were included. The mean FAOS scores improved from a preoperative score of 51.9 ± 16.0 to 75.3 ± 21.9 (P < 0.001). Increasing lesion size was variable associated with inferior FAOS scores (R2 = 0.2228). There was statistically significant higher mean T2 relaxation values at the superficial layer at the site of the AOT graft (42.9 ± 5.2 ms) compared to the superficial layer of the adjacent native cartilage (35.8 ± 3.8 ms) (P < 0.001). Seventeen complications (43.6%) were observed, the most common of which was anterior ankle impingement (25.6%). There were 2 failures (5.1%), both of which had a history of prior bone marrow stimulation via microfracture and post-operative cysts identified on MRI.

CONCLUSION

This retrospective review found that AOT for the treatment of large OLTs produced a 94.9% survival rate at a minimum of 10-year follow-up. Increasing lesion size was associated with inferior clinical outcomes. The findings of this study indicates that AOT is a viable long-term surgical strategy for the treatment of large OLTs.

Effect of amniotic suspension allograft in a rat destabilization of medial meniscus osteoarthritis model

Placental-derived allografts have been of interest as a potential nonsurgical treatment to reduce pain and improve function in knee osteoarthritis (OA). The purpose of this study was to evaluate the effect of single and repeat injection of amniotic suspension allograft (ASA) on pain, function, and cytokine levels using a destabilization of the medial meniscus (DMM) rat model of OA. Post-DMM surgery, animals were treated with a single injection of either ASA, vehicle, or triamcinolone, or repeated injection of either ASA or vehicle. Behavioral testing including knee swelling, pain threshold, dynamic weight bearing (DWB), and gait analysis were evaluated during the in-life phase. Postsacrifice, histopathology and serum and synovial fluid analyses were evaluated. Significant improvements in both DWB differentials and pain threshold were seen in response to repeated injection of ASA, while a single injection of ASA and triamcinolone resulted in significant improvements in pain threshold. Histopathology analysis found no significant differences regardless of treatment compared to vehicle, except for an increase in synovitis following repeated injection of ASA. A single injection of ASA and triamcinolone resulted in increased anti-inflammatory cytokines; repeated ASA injection resulted in significant increases in several immune-modulating factors relevant to OA. When comparing the impact of single and repeat ASA treatments on behavioral testing, repeated injection provided significant additional improvements in both pain and function. This study provides evidence demonstrating the impact of a second injection while also providing additional data for evaluating the use of ASA as a nonsurgical treatment for knee OA.

Enhancing Endogenous Hyaluronic Acid in Osteoarthritic Joints with an Anti-Inflammatory Supramolecular Nanofiber Hydrogel Delivering HAS2 Lentivirus

Osteoarthritis (OA) management remains challenging because of its intricate pathogenesis. Intra-articular injections of drugs, such as glucocorticoids and hyaluronic acid (HA), have certain limitations, including the risk of joint infection, pain, and swelling. Hydrogel-based therapeutic strategies have attracted considerable attention because of their enormous therapeutic potential. Herein, a supramolecular nanofiber hydrogel is developed using dexamethasone sodium phosphate (DexP) as a vector to deliver lentivirus-encoding hyaluronan synthase 2 (HAS2) (HAS2@DexP-Gel). During hydrogel degradation, HAS2 lentivirus and DexP molecules are slowly released. Intra-articular injection of HAS2@DexP-Gel promotes endogenous HA production and suppresses synovial inflammation. Additionally, HAS2@DexP-Gel reduces subchondral bone resorption in the anterior cruciate ligament transection-induced OA mice, attenuates cartilage degeneration, and delays OA progression. HAS2@DexP-Gel exhibited good biocompatibility both in vitro and in vivo. The therapeutic mechanisms of the HAS2@DexP-Gel are investigated using single-cell RNA sequencing. HAS2@DexP-Gel optimizes the microenvironment of the synovial tissue by modulating the proportion of synovial cell subpopulations and regulating the interactions between synovial fibroblasts and macrophages. The innovative nanofiber hydrogel, HAS2@DexP-Gel, effectively enhances endogenous HA production while reducing synovial inflammation. This comprehensive approach holds promise for improving joint function, alleviating pain, and slowing OA progression, thereby providing significant benefits to patients.

Corticosteroid injections for knee osteoarthritis offer clinical benefits similar to hyaluronic acid and lower than platelet-rich plasma: a systematic review and meta-analysis

Purpose

Intra-articular corticosteroid (CS) injections for knee osteoarthritis (OA) management are endorsed by several scientific societies, while the use of hyaluronic acid (HA) and platelet-rich plasma (PRP) is more controversial. Aim of the study was to quantify and compare the clinical effectiveness of CS injections with respect to HA and PRP in patients with knee OA.

Methods

The search was conducted on PubMed, Cochrane, and Web of Science following the PRISMA guidelines. Randomized controlled trials (RCTs) on the comparison of CS injections and HA or PRP injections for the treatment of knee OA were included. The minimal clinically important difference (MCID) was used to interpret the clinical relevance of the improvements at different follow-ups up to 12 months. The study quality was assessed using the Cochrane RoB-2 tool and the GRADE guidelines.

Results

Thirty-five RCTs were included (3348 patients). The meta-analysis comparing CS and HA revealed no difference in terms of WOMAC improvement, while HA showed superior VAS pain improvement at long-term follow-up (P = 0.011), without reaching the MCID. PRP offered a superior WOMAC improvement compared to CS at short- (P = 0.002), mid- (P < 0.001, exceeding the MCID), and long-term (P < 0.001, exceeding the MCID) follow-ups. PRP offered a superior VAS improvement at mid- (P < 0.001, exceeding the MCID) and long-term (P = 0.023) follow-ups.

Conclusion

CS injections for knee OA offer similar results to HA and PRP only at short term, while there is an overall superiority of PRP at longer follow-ups. This difference is not only statistically significant but also clinically relevant in favour of PRP.

Identification of biomarkers related to tryptophan metabolism in osteoarthritis

Background

OA (osteoarthritis) is a common joint disease characterized by damage to the articular cartilage and affects the entire joint tissue, with its main manifestations being joint pain, stiffness, and limited movement.Currently,we know that OA is a complex process composed of inflammatory and metabolic factors.It is reported that the occurrence and development of OA is related to the change of tryptophan metabolism.Therefore, the study of tryptophan metabolism and OA related genes is hopeful to find a new therapeutic target for OA.

Methods

Differentially expressed genes (DEGs) in GSE55235 were gained via differential expression analysis (OA samples vs normal samples). The tryptophan metabolic related DEGs (TMR-DEGs) were obtained by overlapping tryptophan metabolism related genes (TMRGs) and DEGs. Further, biomarkers were screening via Least absolute shrinkage and selection operator (LASSO), naive bayes (NB) and supportvector machine-recursive feature elimination (SVM-RFE) algorithm to establish a diagnostic model. Afterward, Gene Set Enrichment Analysis (GSEA) and drug prediction were performed based on diagnostic biomarkers by multiple software and databases. Eventually, expression level of biomarker public databases was verified using real-time quantitative polymerase chain reaction (RT-qPCR).

Results

Three tryptophan metabolism related biomarkers (TDO2, AOX1 and SLC3A2) were identified in OA. GSEA analysis demonstrated that biomarkers were associated with the function of 'FoxO signaling pathway', 'spliceosome' and 'ribosome'. There were seven drugs with therapeutic potential on TDO2 and AOX1. Ultimately, compared with normal group, expression of AOX1 and SLC3A2 in OA group remarkable lower.

Conclusion

Overall, three tryptophan metabolic related diagnostic biomarkers that associated with OA were obtained, which provided a original direction for the diagnosis and treatment of OA.

Drug-Loaded Bioscaffolds for Osteochondral Regeneration

Osteochondral defect is a complex tissue loss disease caused by arthritis, high-energy trauma, and many other reasons. Due to the unique structural characteristics of osteochondral tissue, the repair process is sophisticated and involves the regeneration of both hyaline cartilage and subchondral bone. However, the current clinical treatments often fall short of achieving the desired outcomes. Tissue engineering bioscaffolds, especially those created via three-dimensional (3D) printing, offer promising solutions for osteochondral defects due to their precisely controllable 3D structures. The microstructure of 3D-printed bioscaffolds provides an excellent physical environment for cell adhesion and proliferation, as well as nutrient transport. Traditional 3D-printed bioscaffolds offer mere physical stimulation, while drug-loaded 3D bioscaffolds accelerate the tissue repair process by synergistically combining drug therapy with physical stimulation. In this review, the physiological characteristics of osteochondral tissue and current treatments of osteochondral defect were reviewed. Subsequently, the latest progress in drug-loaded bioscaffolds was discussed and highlighted in terms of classification, characteristics, and applications. The perspectives of scaffold design, drug control release, and biosafety were also discussed. We hope this article will serve as a valuable reference for the design and development of osteochondral regenerative bioscaffolds and pave the way for the use of drug-loaded bioscaffolds in clinical therapy.

Corticosteroids for the Treatment of Internal Temporomandibular Joint Disorders: A Systematic Review and Network Meta-Analysis

Background: We evaluated the comparative effectiveness of all intra-articular injection corticosteroids for treating internal temporomandibular joint (TMJ) disorders. Methods: We searched MEDLINE, CENTRAL, EMBASE, SCOPUS, and LILACS through December 2023. We included randomized clinical trials (RCTs) enrolling patients with symptomatic internal disorders of the TMJ comparing any type of intra-articular corticosteroid therapy against another or to another minimally invasive therapy. The outcomes of interest were pain, range of mandibular motion (RoM), quality of life (QoL) and adverse effects at 1, 3, 6, and 12 months. We assessed the risk of bias using the Cochrane Collaboration's tool. We conducted a frequentist network meta-analysis and assessed the certainty of the evidence (CoE) using GRADE. Results: We included 20 RCTs enrolling 810 participants, which assessed five corticosteroids alone or combined with arthrocentesis or hyaluronic acid. Based on moderate CoE, betamethasone is among the most effective corticosteroids for reducing pain at one (mean difference compared to arthrocentesis [MD], -3.80; 95% confidence interval [CI], -4.55 to -3.05) and three months (MD, -2.74; 95%CI, -3.42 to -2.06), and arthrocentesis plus dexamethasone at six months (MD, -0.80; 95%CI, -1.57 to -0.03). There was no convincing evidence that any intervention was better than arthrocentesis for improving the RoM and QoL at any follow-up time. Methylprednisolone may be more harmful than arthrocentesis for adverse effects. Discussion: Betamethasone and arthrocentesis plus dexamethasone are the most effective in managing pain in the short and medium term compared to arthrocentesis (moderate CoE). Decisions about their use should consider other factors, such as costs, feasibility, and acceptability. Future research should consider QoL as an outcome and assess participants at longer follow-up periods.

Corticosteroid injection of the knee within one month prior to meniscus repair increases the risk of repair failure requiring meniscectomy

OBJECTIVE

Meniscal tears are common knee injuries with limited endogenous healing capacity. This study aimed to investigate the association between the timing and administration of preoperative intra-articular corticosteroid injections (CSIs) and the risk of subsequent meniscectomy following meniscus repair.

METHODS

Using a national insurance claims database, patients aged 18-40 years undergoing meniscus repair within six months of tear diagnosis were studied. Patients were categorized based on whether they received preoperative CSIs within three intervals prior to repair. Multivariable logistic regression was used to analyze the risk of follow-up meniscectomy while controlling for various patient-related variables.

RESULTS

Among 5,390 patients meeting inclusion criteria, 201 received preoperative CSIs. The CSI group was older and had higher rates of diabetes, obesity, and knee osteoarthritis. The overall rate of follow-up meniscectomy did not differ between groups. However, CSIs performed within one month prior to repair were associated with significantly higher odds of subsequent meniscectomy compared to CSIs performed between three and six months prior. Obesity, tobacco use, and knee osteoarthritis were also independently associated with higher risk, while increasing age was associated with lower risk.

CONCLUSION

The study highlights an increased risk of repair failure requiring follow-up meniscectomy for patients receiving intra-articular CSIs within one month prior to meniscus repair. These findings suggest caution when considering CSIs as a treatment option for patients scheduled for meniscus repair. Further research is needed to establish optimal timing guidelines for CSIs in relation to meniscus repair and to understand the underlying mechanisms.

The effect of intra-articular steroid injection on the cartilage and tendon thicknesses in juvenile idiopathic arthritis

OBJECTIVES

Intra-articular corticosteroid injection (IACI) is a safe first-line or adjunct therapy used in any subtype of juvenile idiopathic arthritis (JIA). Limited studies evaluated the effect of IACI on cartilage. Our study aimed to examine the femoral cartilage thickness of patients with JIA who received IACI to the knee joint using ultrasound.

METHODS

We randomly selected JIA patients who performed IACI in the knee joint. Baseline bilateral joint cartilage and tendon thicknesses were measured. The articular fluid was aspirated, and applied IACI at the same period. Six months after injection, the exact measurements were repeated. Distal femoral cartilage, quadriceps tendon, and distal and proximal patellar tendon thicknesses were compared at the baseline (before IACI) and 6 months after IACI.

RESULTS

Thirty patients with JIA were included, and 23 (76.7%) were female. The median age was 11 years (interquartile range, 6 to 14), and the median disease duration was 3.3 years (interquartile range, 5 months to 5 years). The subtypes of JIA were oligoarticular in 25 (83.3%), polyarticular in 2 (6.7%), enthesitis-related arthritis in 2 (6.7%), and juvenile psoriatic arthritis in 1 (3.3%). Distal femoral cartilage thickness was 2.96 ± 0.79 mm at baseline and 2.85 ± 0.70 mm at 6 months after IACI (P = .35). The tendon thicknesses were similar at 6 months after baseline measurements.

CONCLUSIONS

Our findings reveal that knee IACI in patients with JIA did not significantly change cartilage and tendon thicknesses. This observation could indicate that IACIs have no detrimental effects on the cartilage and the tendons.

Platelet-Rich Plasma Injections for the Treatment of Degenerative Orthopedic Conditions

Platelet-rich plasma injections for the treatment of degenerative orthopedic conditions have good evidence for safety, pain relief, and functional improvement. The U.S. Military is providing platelet-rich plasma services for military services members and TRICARE beneficiaries. The use of this safe and effective treatment should be continued and expanded.

Intra-articular injection of stigmasterol-loaded nanoparticles reduce pain and inhibit the inflammation and joint destruction in osteoarthritis rat model: A pilot study

Stigmasterol, a plant-derived sterol, sharing structural similarity with cholesterol, has demonstrated anti-osteoarthritis (OA) properties, attributed to its antioxidant and anti-inflammatory capabilities. Given that OA often arises in weight bearing or overused joints, prolonged localized treatment effectively targets inflammatory aspects of the disease. This research explored the impact of stigmasterol-loaded nanoparticles delivered via intra-articular injections in an OA rat model. Employing mesoporous silica nanomaterials (MSNs) combined with β-cyclodextrin (β-CD) as a vehicle, stigmasterol was loaded in conjunction with tannic acid, forming stigmasterol/β-CD-MSNs to facilitate a sustained stigmasterol release. The study employed RAW 264.7 cells to examine the in vitro cytotoxicity and anti-inflammatory effect of stigmasterol/β-CD-MSNs. For in vivo experimentation, we used healthy control rats and monosodium iodoacetate (MIA)-induced OA rats, separated into five groups, varying the injection substances. In vitro findings indicated that stigmasterol/β-CD-MSNs suppressed the mRNA expression of key pro-inflammatory mediators such as interleukin-6, tumor necrosis factor-α, and matrix metalloproteinase-3 in a dose-dependent manner. In vivo experiments revealed a substantial decrease in the mRNA levels of pro-inflammatory factors in the stigmasterol(50 µg)/β-CD-MSN group compared to the others. Macroscopic, radiographic, and histological evaluations established that intra-articular injections of stigmasterol/β-CD-MSNs inhibited cartilage degeneration and subchondral bone deterioration. Therefore, in a chemically induced OA rat model, intra-articular stigmasterol delivery was associated with reduction in both local and systemic inflammatory responses, alongside a slowdown in joint degradation and arthritic progression.

Outcomes of surgical treatment of tracheobronchomalacia in children

BACKGROUND

Tracheobronchomalacia (TBM) is characterized by excessive dynamic airway collapse. Severe TBM can be associated with substantial morbidity. Children with secondary TBM associated with esophageal atresia/tracheoesophageal fistula (EA/TEF) and vascular-related airway compression (VRAC) demonstrate clinical improvement following airway pexy surgery. It is unclear if children with severe primary TBM, without secondary etiologies (EA/TEF, vascular ring, intrinsic pulmonary pathology, or complex cardiac disease) demonstrate clinical improvement following airway pexy surgery.

MATERIALS AND METHODS

The study cohort consisted of 73 children with severe primary TBM who underwent airway pexy surgery between 2013 and 2020 at Boston Children's Hospital. Pre- and postoperative symptoms as well as bronchoscopic findings were compared with Fisher exact test for categorical data and Student's t-test for continuous data.

RESULTS

Statistically significant improvements in clinical symptoms were observed, including cough, noisy breathing, prolonged respiratory infections, pneumonias, exercise intolerance, cyanotic spells, brief resolved unexplained events (BRUE), and noninvasive positive pressure ventilation (NIPPV) dependence. No significant differences were seen regarding oxygen dependence, ventilator dependence, or respiratory distress requiring NIPPV. Comparison of pre- and postoperative dynamic bronchoscopy findings revealed statistically significant improvement in the percent of airway collapse in all anatomic locations except at the level of the upper trachea (usually not malacic). Despite some initial improvements, 21 (29%) patients remained symptomatic and underwent additional airway pexies with improvement in symptoms.

CONCLUSION

Airway pexy surgery resulted in significant improvement in clinical symptoms and bronchoscopic findings for children with severe primary TBM; however, future prospective and long-term studies are needed to confirm this benefit.

Intra-articular steroids for the treatment of coxarthrosis; a retrospective cohort study comparing three contrast techniques

INTRODUCTION

Intra-articular steroid injections (IAS) are a treatment for coxarthrosis. This study examines the efficacy of three fluoroscopy-guided IAS contrast techniques for coxarthrosis: contrast-assisted (Iohexol), air arthrogram-assisted and blind (contrast/air free) and stratifies efficacy based on multiple patient variables.

MATERIALS AND METHODS

A cohort of 307 hip IAS was retrospectively analysed over a four-year period. The primary outcome was efficacy of IAS between each technique group, defined by duration of symptomatic relief. The secondary outcome was efficacy based on multiple patient variables. Variables included age, BMI, gender, type of osteoarthritis, grade of osteoarthritis, smoking status, co-morbidity index and duration of pre-injection symptoms. Chi-squared, Pearson, One Way ANOVA and F-tests were used for statistical analysis.

RESULTS

Total failure (< 1 week symptomatic relief) was 20% (contrast 20%, air 14%, blind 26%). >3 months of symptomatic relief was experienced by 35%, with the air arthrogram technique containing the largest proportion of IAS achieving > 3months of relief within its own group (contrast 35%, air 38%, blind 28%). Non-smokers experienced a longer duration of symptomatic relief in the air arthrogram group (p = 0.04). Older patients had a longer duration of symptomatic relief with the blind technique (p = < 0.001). There were no significant differences between the three techniques based on the other patient variables.

CONCLUSION

Air arthrogram is an effective method of confirming injection placement in hip IAS for coxarthrosis and the use of a contrast agent (e.g., Iohexol) may not be required. Non-contrast techniques may produce longer duration of symptomatic relief in non-smokers and in older patients.

Chondrotoxicity of Intra-Articular Injection Treatment: A Scoping Review

The purpose of this scoping review was to identify possible chondrotoxic effects caused by drugs usually used for intra-articular injections. PubMed, Scopus, Web of Science and Cochrane were searched. Inclusion criteria required randomized controlled trials written in English that evaluate the toxic effect that damages the cartilage. The literature search resulted in 185 unique articles. 133 full-text articles were screened for inclusion, of which 65 were included. Corticosteroids, with the exception of triamcinolone, along with local anaesthetics, potentially excluding ropivacaine and liposomal bupivacaine, and nonsteroidal anti-inflammatory drugs, exhibited insufficient safety profiles to warrant casual use in clinical settings. Hyaluronic acid, on the other hand, appears to demonstrate safety while also mitigating risks associated with concurrent compounds, thereby facilitating therapeutic combinations. Additionally, there remains a paucity of data regarding platelet-rich plasma, necessitating further evaluation of its potential efficacy and safety. Overall, it seems that results are significantly influenced by the dosage and frequency of injections administered, observed in both human and animal studies.

Efficacy of Intra-Articular Corticosteroid Injection for Nonsurgical Management of Trapeziometacarpal Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

PURPOSE

As osteoarthritis (OA) of the trapeziometacarpal (TMC) joint leads to a high degree of disease burden with compromises in rudimentary and fine movements of the hand, intra-articular injections may be a desirable treatment option. However, because there are no evidence-based guidelines, the choice of intra-articular injection type is left to the discretion of the individual surgeon in collaboration with the patient. The purpose of our study was to perform a systematic review and meta-analysis using level I studies to compare outcomes following corticosteroid and alternative methods of intra-articular injections for the management of TMC OA. Our hypothesis was that intra-articular corticosteroid injections were no more effective than other methods of intra-articular injections for the management of TMC OA.

METHODS

A systematic literature search was performed. Eligible for inclusion were randomized control trials reporting on intra-articular corticosteroid injection for the management of TMC OA. Clinical outcomes were recorded.

RESULTS

The 10 included studies comprised 673 patients. The mean age was 57.8 ± 8.3 years, with a mean follow-up of 6.4 ± 2.7 months. There was no significant difference in visual analog scale scores, grip strength and tip pinch strength between corticosteroids and hyaluronic acid at short- and medium-term follow-up. Further, there was no difference in visual analog scale pain scores at rest at medium-term follow-up between corticosteroids and platelet-rich plasma.

CONCLUSIONS

Despite short-term improvement with intra-articular corticosteroid injections, there was no significant difference in pain and functional outcomes following intra-articular corticosteroid injections compared to hyaluronic acid or platelet-rich plasma administration. Given the affordability, ease of administration, and efficacy associated with corticosteroids, they are a favorable option when considering the choice of intra-articular injection for the management of TMC OA.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Zwitterionic polymer-dexamethasone conjugates penetrate and protect cartilage from inflammation

Improving the pharmacokinetics of intra-articularly injected therapeutics is a major challenge in treating joint disease. Small molecules and biologics are often cleared from the joint within hours, which greatly reduces their therapeutic efficacy. Furthermore, they are often injected at high doses, which can lead to local cytotoxicity and systemic side effects. In this study, we present modular polymer-drug conjugates of zwitterionic poly(carboxybetaine acrylamide) (pCBAA) and the anti-inflammatory glucocorticoid dexamethasone (DEX) to create cartilage-targeted carriers with slow-release kinetics. pCBAA polymers showed excellent cartilage penetration (full thickness in 1 h) and retention (>50 % after 2 weeks of washing). DEX was loaded onto the pCBAA polymer by employing two different DEX-bearing comonomers to produce pCBAA-co-DEX conjugates with different release kinetics. The slow-releasing conjugate showed zero-order release kinetics in PBS over 70 days. The conjugates elicited no oxidative stress on chondrocytes compared to dose-matched free DEX and protected bovine cartilage explants from the inflammatory response after treatment with IL-1β. By combining cartilage targeting and sustained drug release properties, the pCBAA-co-DEX conjugates solve many issues of today's intra-articular therapeutics, which could ultimately enable better long-term clinical outcomes with fewer side effects.

Periprosthetic Joint Infection Risk After Primary Total Knee Arthroplasty: Are All Preoperative Corticosteroid Injections the Same?

BACKGROUND

Previous evidence has demonstrated an increased risk of periprosthetic joint infection (PJI) following primary total knee arthroplasty (TKA) in patients receiving corticosteroid injection (CSI) within 3 months of surgery. The study aimed to determine if PJI risk after TKA varied among different corticosteroid agents.

METHODS

A total of 85,073 patients undergoing primary TKA from 2009 to 2019 were identified from a large national database. Of these, 1,092 (1.3%) received an ipsilateral, intra-articular CSI within 90 days of TKA. These patients were compared to those not receiving CSI using multivariate logistic regressions following 1:4 propensity score matching, with PJI development as the primary outcome.

RESULTS

Patients given an injection of any corticosteroid within 90 days of TKA had significantly higher PJI rates compared to controls (1.6 versus 0.41%; P < .001). This finding was driven by patients receiving methylprednisolone acetate (n = 543) or betamethasone (n = 153), with prevalence rates of 1.7 and 2.6%, respectively (P = .003 and P = .01, respectively). No significant increase in the rate of PJI was observed for patients receiving triamcinolone (1.2%; P = .08; n = 342) or dexamethasone (0.0%; P = 1; n = 54) within 90 days preceding TKA. PJI risk for all agents, administered more than 90 days preoperatively normalized to control levels (0.51 versus 0.34%).

CONCLUSIONS

These results suggest that PJI risk varies with CSI type. In this large database study, only patients given methylprednisolone acetate or betamethasone injections within 90 days of surgery had significantly higher PJI rates compared to controls.

Single dose thermoresponsive dexamethasone prodrug completely mitigates joint pain for 15 weeks in a murine model of osteoarthritis

In this study, we aimed to assess the analgesic efficacy of a thermoresponsive polymeric dexamethasone (Dex) prodrug (ProGel-Dex) in a mouse model of osteoarthritis (OA). At 12 weeks post model establishment, the OA mice received a single intra-articular (IA) injection of ProGel-Dex, dose-equivalent Dex, or Saline. Comparing to Saline and Dex controls, ProGel-Dex provided complete and sustained pain relief for >15 weeks according to incapacitance tests. In vivo optical imaging confirmed the continuous presence of ProGel-Dex in joints for 15 weeks post-injection. According to micro-CT analysis, ProGel-Dex treated mice had significantly lower subchondral bone thickness and medial meniscus bone volume than Dex and Saline controls. Except for a transient delay of body weight increase and slightly lower endpoint liver and spleen weights, no other adverse effect was observed after ProGel-Dex treatment. These findings support ProGel-Dex's potential as a potent and safe analgesic candidate for management of OA pain.

Knee Joint Preservation in Tactical Athletes: A Comprehensive Approach Based upon Lesion Location and Restoration of the Osteochondral Unit

The unique physical demands of tactical athletes put immense stress on the knee joint, making these individuals susceptible to injury. In order to ensure operational readiness, management options must restore and preserve the native architecture and minimize downtime, while optimizing functionality. Osteochondral lesions (OCL) of the knee have long been acknowledged as significant sources of knee pain and functional deficits. The management of OCL is predicated on certain injury characteristics, including lesion location and the extent of subchondral disease. Techniques such as marrow stimulation, allograft and autologous chondrocyte implantation are examined in detail, with a focus on their application and suitability in tactical athlete populations. Moreover, the restoration of the osteochondral unit (OCU) is highlighted as a central aspect of knee joint preservation. The discussion encompasses the biomechanical considerations and outcomes associated with various cartilage restoration techniques. Factors influencing procedure selection, including lesion size, location, and patient-specific variables, are thoroughly examined. Additionally, the review underscores the critical role of post-operative rehabilitation and conditioning programs in optimizing outcomes. Strengthening the surrounding musculature, enhancing joint stability, and refining movement patterns are paramount in facilitating the successful integration of preservation procedures. This narrative review aims to provide a comprehensive resource for surgeons, engineers, and sports medicine practitioners engaged in the care of tactical athletes and the field of cartilage restoration. The integration of advanced preservation techniques and tailored rehabilitation protocols offers a promising avenue for sustaining knee joint health and function in this demanding population.

In vitro inflammatory multi-cellular model of osteoarthritis

Objective

Osteoarthritis (OA) is a chronic joint disease, with limited treatment options, characterized by inflammation and matrix degradation, and resulting in severe pain or disability. Progressive inflammatory interaction among key cell types, including chondrocytes and macrophages, leads to a cascade of intra- and inter-cellular events which culminate in OA induction. In order to investigate these interactions, we developed a multi-cellular in vitro OA model, to characterize OA progression, and identify and evaluate potential OA therapeutics in response to mediators representing graded levels of inflammatory severity.

Methods

We compared macrophages, chondrocytes and their co-culture responses to "low" Interleukin-1 (IL-1) or "high" IL-1/tumor necrosis factor (IL-1/TNF) levels of inflammation. We also investigated response changes following the administration of dexamethasone (DEX) or mesenchymal stromal cell (MSC) treatment via a combination of gene expression and secretory changes, reflecting not only inflammation, but also chondrocyte function.

Results

Inflamed chondrocytes presented an osteoarthritic-like phenotype characterized by high gene expression of pro-inflammatory cytokines and chemokines, up-regulation of ECM degrading proteases, and down-regulation of chondrogenic genes. Our results indicate that while MSC treatment attenuates macrophage inflammation directly, it does not reduce chondrocyte inflammatory responses, unless macrophages are present as well. DEX however, can directly attenuate chondrocyte inflammation.

Conclusions

Our results highlight the importance of considering multi-cellular interactions when studying complex systems such as the articular joint. In addition, our approach, using a panel of both inflammatory and chondrocyte functional genes, provides a more comprehensive approach to investigate disease biomarkers, and responses to treatment.

Transient receptor potential vanilloid 1: A potential therapeutic target for the treatment of osteoarthritis and rheumatoid arthritis

This study aims to determine the molecular mechanisms and analgesic effects of transient receptor potential vanilloid 1 (TRPV1) in the treatments of osteoarthritis (OA) and rheumatoid arthritis (RA). We summarize and analyse current studies regarding the biological functions and mechanisms of TRPV1 in arthritis. We search and analyse the related literature in Google Scholar, Web of Science and PubMed databases from inception to September 2023 through the multi-combination of keywords like 'TRPV1', 'ion channel', 'osteoarthritis', 'rheumatoid arthritis' and 'pain'. TRPV1 plays a crucial role in regulating downstream gene expression and maintaining cellular function and homeostasis, especially in chondrocytes, synovial fibroblasts, macrophages and osteoclasts. In addition, TRPV1 is located in sensory nerve endings and plays an important role in nerve sensitization, defunctionalization or central sensitization. TRPV1 is a non-selective cation channel protein. Extensive evidence in recent years has established the significant involvement of TRPV1 in the development of arthritis pain and inflammation, positioning it as a promising therapeutic target for arthritis. TRPV1 likely represents a feasible therapeutic target for the treatment of OA and RA.

Intra-articular corticosteroid injections provide a clinically relevant benefit compared to placebo only at short-term follow-up in patients with knee osteoarthritis: A systematic review and meta-analysis

PURPOSE

To quantify the clinical relevance of intra-articular corticosteroid effects compared to placebo for the injective treatment of knee osteoarthritis (OA).

METHODS

The PubMed, Cochrane Library and Web of Science databases were searched on May 3, 2023. This study was conducted in accordance with the PRISMA guidelines. The inclusion criteria were randomized controlled trials (RCTs), published in English, with no time limitation regarding publication date, comparing intra-articular corticosteroids and placebo injections for knee OA. The effects were quantified at short- (≤6 weeks), mid- (>6 weeks and ≤3 months), and long-term (≥6 months) follow-ups. The minimal clinically important difference (MCID) for the outcomes (visual analogue scale for pain - VAS: 1.4, Western Ontario and McMaster University Osteoarthritis Index - WOMAC: 9) was used to interpret the clinical improvement provided by intra-articular corticosteroid injections compared to placebo. The quality of each article was assessed using the Cochrane RoB 2 tool and the GRADE guidelines.

RESULTS

Among the 1030 articles retrieved, 11 RCTs (842 patients) were included. A comparison of the two groups revealed statistically significant differences in the improvement of VAS and WOMAC scores in terms of the mean difference (MD); this difference was in favour of corticosteroids at short-term (p < 0.001, MD = -1.6 and p < 0.001, MD = -9.9, respectively) and mid-term follow-ups (p = 0.001, mean MD = -1.3 and p = 0.005, MD = -4.9, respectively). No difference was observed at the long-term follow-up. The MDs between the improvements in the two groups reached the MCID values for the VAS and WOMAC only at the short-term follow-up. The RoB 2 tool and the GRADE evaluations showed the presence of risk of bias and limited quality of evidence.

CONCLUSION

This systematic review and meta-analysis demonstrated that intra-articular corticosteroid injections offer clinically perceivable pain relief and functional improvement higher than the placebo effect only at short-term follow-up in patients affected by knee OA, with benefits losing clinical relevance already after 6 weeks. These results, together with the low number and the limited quality of the RCTs comparing this treatment with placebo, question the indication for the use of corticosteroid injections in clinical practice for the treatment of knee OA.

LEVEL OF EVIDENCE

Level I.

Efficacy of ozone injections for reducing musculoskeletal pain in comparison with corticosteroid injections: A systematic review and meta-analysis

BACKGROUND

Corticosteroid injections are frequently used in the short-term treatment of musculoskeletal pain, but their use is controversial as repeated exposures to corticosteroids can lead to deleterious effects on musculoskeletal tissue. Ozone injections have been proposed as a possible treatment for musculoskeletal pain; however, their effectiveness has not been compared with corticosteroids.

OBJECTIVE

To evaluate the effectiveness of ozone injections for reducing pain in individuals with musculoskeletal pain in comparison with corticosteroid injections through a meta-analysis.

METHODS

An online systematic search was performed using electronic databases up to September 2023. We searched for studies that compared corticosteroid injections with ozone injections in the treatment of musculoskeletal pain of diverse origins.

RESULTS

Eleven studies were included comprising a total of 534 individuals. In the overall pooled analysis, a pain reduction in favor of corticosteroid injections was found in the short term (d= 0.31, 95% CI 0.01 to 0.60, p (z) 0.04, I2 = 32%). In the medium term, no significant differences were found in reducing pain between groups (d=-0.17, 95% CI -0.42 to 0.07, p (z) 0.15, I2 = 0%).

CONCLUSIONS

Our results suggest that corticosteroids injections are more effective in reducing musculoskeletal pain in the short term, but equally effective in the medium term when compared with ozone injections. Nonetheless, better-quality clinical trials are necessary to corroborate these results.

Injectable hydrogels: An emerging therapeutic strategy for cartilage regeneration

The impairment of articular cartilage due to traumatic incidents or osteoarthritis has posed significant challenges for healthcare practitioners, researchers, and individuals suffering from these conditions. Due to the absence of an approved treatment strategy for the complete restoration of cartilage defects to their native state, the tissue condition often deteriorates over time, leading to osteoarthritic (OA). However, recent advancements in the field of regenerative medicine have unveiled promising prospects through the utilization of injectable hydrogels. This versatile class of biomaterials, characterized by their ability to emulate the characteristics of native articular cartilage, offers the distinct advantage of minimally invasive administration directly to the site of damage. These hydrogels can also serve as ideal delivery vehicles for a diverse range of bioactive agents, including growth factors, anti-inflammatory drugs, steroids, and cells. The controlled release of such biologically active molecules from hydrogel scaffolds can accelerate cartilage healing, stimulate chondrogenesis, and modulate the inflammatory microenvironment to halt osteoarthritic progression. The present review aims to describe the methods used to design injectable hydrogels, expound upon their applications as delivery vehicles of biologically active molecules, and provide an update on recent advances in leveraging these delivery systems to foster articular cartilage regeneration.

Pioglitazone-Loaded Cartilage-Targeted Nanomicelles (Pio@C-HA-DOs) for Osteoarthritis Treatment

Background

Hyaluronic acid (HA) is a popular biological material for osteoarthritis (OA) treatment. Pioglitazone, a PPAR-γ agonist, has been found to inhibit OA, but its use is limited because achieving the desired local drug concentration after administration is challenging.

Purpose

Herein, we constructed HA-based cartilage-targeted nanomicelles (C-HA-DOs) to deliver pioglitazone in a sustained manner and evaluated their efficacy in vitro and in vivo.

Methods

C-HA-DOs were chemically synthesized with HA and the WYRGRL peptide and dodecylamine. The products were characterized by FT-IR, 1H NMR, zeta potential and TEM. The drug loading rate and cumulative, sustained drug release from Pio@C-HA-DOs were determined, and their biocompatibility and effect on oxidative stress in chondrocytes were evaluated. The uptake of C-HA-DOs by chondrocytes and their effect on OA-related genes were examined in vitro. The nanomicelle distribution in the joint cavity was observed by in vivo small animal fluorescence imaging (IVIS). The therapeutic effects of C-HA-DOs and Pio@C-HA-DOs in OA rats were analysed histologically.

Results

The C-HA-DOs had a particle size of 198.4±2.431 nm, a surface charge of -8.290±0.308 mV, and a critical micelle concentration of 25.66 mg/Land were stable in solution. The cumulative drug release from the Pio@C-HA-DOs was approximately 40% at pH 7.4 over 24 hours and approximately 50% at pH 6.4 over 4 hours. Chondrocytes rapidly take up C-HA-DOs, and the uptake efficiency is higher under oxidative stress. In chondrocytes, C-HA-DOs, and Pio@C-HA-DOs inhibited H2O2-induced death, reduced intracellular ROS levels, and restored the mitochondrial membrane potential. The IVIS images confirmed that the micelles target cartilage. Pio@C-HA-DOs reduced the degradation of collagen II and proteoglycans by inhibiting the expression of MMP and ADAMTS, ultimately delaying OA progression in vitro and in vivo.

Conclusion

Herein, C-HA-DOs provided targeted drug delivery to articular cartilage and improved the role of pioglitazone in the treatment of OA.

Intraarticular Injections in the Foot and Ankle: Medication Selection Patterns and Perceived Risk Of Chondrotoxicity

Background

Intraarticular corticosteroid injections (ICIs) are widely used to treat foot and ankle conditions. Although laboratory studies indicate certain corticosteroids and local anesthetics used in ICIs are associated with chondrotoxic effects, and selected agents such as ropivacaine and triamcinolone may have less of these features, clinical evidence is lacking. We aimed to identify the patterns of drug selection, perceptions of injectate chondrotoxicity, and rationale for medication choice among surgeons in the American Orthopaedic Foot & Ankle Society (AOFAS).

Methods

An e-survey including demographics, practice patterns, and rationale was disseminated to 2011 AOFAS members. Frequencies and percentages were calculated for demographic data, anesthetic and steroid choice, rationale for injectate choice, and perception of chondrotoxicity. Bivariate analysis was used to identify practice patterns significantly associated with perceptions of injectate risk and rationale.

Results

In total, 387 surveys were completed. Lidocaine and triamcinolone were the most common anesthetic and corticosteroid used (51.2% and 39.3%, respectively). Less than half of respondents felt corticosteroids or local anesthetics bear risk of chondrotoxicity. Respondents agreeing that corticosteroids are chondrotoxic were more likely to use triamcinolone (P = .037). Respondents agreeing local anesthetics risk chondrotoxicity were less likely to use lidocaine (P = .023). Respondents choosing a local anesthetic based on literature were more likely to use ropivacaine (P < .001).

Conclusion

Corticosteroid and local anesthetic use in ICIs varied greatly. Rationale for ICI formulation was also variable, as the clinical implications are largely unknown. Those who recognized potential chondrotoxicity and who chose based on literature were more likely to choose ropivacaine and triamcinolone, as reflected in the basic science literature. Further clinical studies are needed to establish guidelines that shape foot and ankle ICI practices based on scientific evidence and reduce the variation identified by this study.

Level of Evidence

Level IV, cross-sectional survey study.

Allogenic Platelet-Rich Plasma for the Treatment of Adhesive Capsulitis

Adhesive capsulitis (AC) is a common shoulder disorder leading to pain and restricted range of motion (ROM) and affects the patient's activities of daily living (ADL) and overall quality of life (QoL). Conservative therapies are prioritized, resorting to surgical intervention only when necessary. Unfortunately, these modalities have limitations and do not address the underlying pathological cause of AC. The use of autologous biologics, such as platelet-rich plasma (PRP), has evolved and shown promise for managing musculoskeletal (MSK) injuries, including AC. However, subpar functional outcomes have led clinicians to question the long-term efficacy of autologous PRP. To circumvent this, the possibility of utilizing a standardized and well-characterized allogenic PRP for AC has been explored. In this manuscript, we qualitatively present in vitro, pre-clinical, clinical, and ongoing studies investigating the varied applications of allogenic PRP for the management of AC. The results demonstrated that allogenic PRP acts in a pleiotropic manner and decreases pro-inflammatory cytokines only in the inflammatory condition. In addition, the administration of allogenic PRP is safe and potentially efficacious, in terms of reducing pain and improving range of motion, shoulder strength, and function, in non-surgical management of AC. Nonetheless, more pre-clinical studies and adequately powered, multicenter, prospective, non-randomized, and randomized controlled trials with longer follow-up are warranted to further establish the safety and efficacy of allogenic PRP and justify its routine clinical use.

Umbilical Cord Stem Cell Lysate: A New Biologic Injectate for the Putative Treatment of Acute Temporomandibular Joint Inflammation

Objective

To compare in vivo, the acute anti-inflammatory effects of a lysate derived from human umbilical perivascular mesenchymal cells with the cells themselves in both an established hind-paw model of carrageenan-induced inflammation and also in the inflamed temporomandibular joint.

Study Design

Human umbilical cord perivascular cells were harvested and cultured in xeno- and serum-free conditions to P3. In addition, P3 cells were used to prepare a proprietary 0.22 micron filtered lysate. First, CD1 immunocompetent mice underwent unilateral hind-paw injections of carrageenan for induction of inflammation, followed immediately by treatment with saline (negative control), 1% cell lysate, or viable cells. The contralateral paw remained un-injected with carrageenan. Paw circumference was measured prior to injections and 48 hr later and myeloperoxidase and TNF-alpha concentrations were measured post-sacrifice in excised tissue. Second, immunocompetent Male Wistar rats underwent unilateral intra-articular temporomandibular (TMJ) injections from the same treatment groups and were sacrificed at 4 and 48 hr post-injection. The contralateral TMJ remained un-injected with carrageenan. Articular tissue and synovial aspirates, from the treated TMJ were obtained for histologic and leukocyte infiltration analyses.

Results

The lysate and cell-treated hind-paw demonstrated reduced tissue edema, and significantly lower concentrations of myeloperoxidase and TNF-alpha at 48 hr compared to untreated controls. Treated TMJs demonstrated lower concentrations of leukocytes in the synovium compared to controls and histologic evidence, in the peri-articular tissue, of reduced inflammation.

Conclusion

In this preliminary study, both the human umbilical perivascular cells and a highly diluted lysate produced therefrom were anti-inflammatory.

Screening of Anti-Inflammatory Activity and Metabolomics Analysis of Endophytic Fungal Extracts; Identification and Characterization of Perylenequinones and Terpenoids from the Interesting Active Alternaria Endophyte

Patients suffering from inflammatory chronic diseases are classically treated with anti-inflammatory drugs but unfortunately are highly susceptible to becoming resistant to their treatment. Finding new drugs is therefore crucial and urgent and research on endophytic fungi is a promising way forward. Endophytic fungi are microorganisms that colonize healthy plants and live within their intercellular tissues. They are able to produce a large variety of secondary metabolites while allowing their host to stay healthy. A number of these molecules are endowed with antioxidant or antimicrobial as well as cytotoxic properties, making them very interesting/promising in the field of human therapy. The aim of our study was to investigate whether extracts from five endophytic fungi isolated from plants are endowed with anti-inflammatory activity. Extracts of the endophytic fungi Alternaria alternata from Calotropis procera leaves and Aspergillus terreus from Trigonella foenum-graecum seeds were able to counteract the lipopolysaccharide (LPS) pro-inflammatory effect on THP-1 cells differentiated into macrophages. Moreover, they were able to induce an anti-inflammatory state, rendering them less sensitive to the LPS pro-inflammatory stimulus. Taken together, these results show that these both endophytic fungi could be interesting alternatives to conventional anti-inflammatory drugs. To gain more detailed knowledge of their chemical richness, phytochemical analysis of the ethyl acetate extracts of the five endophytic fungi studied was performed using HPTLC, GC-MS and LC-MS with the Global Natural Products Social (GNPS) platform and the MolNetEnhancer tool. A large family of metabolites (carboxylic acids and derivatives, steroid derivatives, alkaloids, hydroxyanthraquinones, valerolactones and perylenequinones) were detected. The purification of endophytic fungus extract of Alternaria alternate, which diminished TNF-α production of 66% at 20 µg/mL, incubated one hour before LPS addition, led to the characterization of eight pure compounds. These molecules are altertoxins I, II, III, tricycloalternarenes 3a, 1b, 2b, anthranilic acid, and o-acetamidobenzoic acid. In the future, all these pure compounds will be evaluated for their anti-inflammatory activity, while altertoxin II has been shown in the literature as the most active mycotoxin in terms of anti-inflammatory activity.

Residual effects of intra-articular betamethasone and triamcinolone acetonide in an equine acute synovitis model

BACKGROUND

Intra-articular (IA) corticosteroids are regularly used in equine athletes for the control of joint inflammation.

OBJECTIVES

The goal of this study was to use an acute synovitis inflammation model to determine the residual effects of IA betamethasone and triamcinolone acetonide on various inflammatory parameters and lameness.

STUDY DESIGN

Crossover randomised trial.

METHODS

Five mixed-breed, 2-year-old horses were randomly allocated to an IA treatment of the radiocarpal joint with 9 mg of either betamethasone or triamcinolone acetonide. Two weeks following treatment, horses were injected with 1 μg of lipopolysaccharide (LPS) diluted in 1 ml of saline. Following LPS injection, horses were crossed-over and both sets of injections were repeated after a washout period. Blood samples were collected at multiple time points for mRNA analysis, as well as serum amyloid A (SAA) and cortisol determination. At each time point, lameness was also subjectively scored. Additional injections with saline-only or LPS-only (twice) were conducted as negative and positive controls, respectively. Two-way repeated measures analysis of variance was used to analyse all data.

RESULTS

Corticosteroid-only treatments result in significant mRNA expression differences, as well as significant and prolonged cortisol suppression. Following LPS injection, there was a residual treatment effect with triamcinolone evidenced by a significant treatment effect on IL-6 and PTGS1 (cyclooxygenase-1), lameness, SAA and cortisol concentrations, while only IL-6 expression was affected by betamethasone.

MAIN LIMITATIONS

The acute synovitis model used here results in significant inflammation and is not representative of the low-grade inflammation seen with typical joint disease and residual anti-inflammatory effects may be more profound in naturally occurring joint disease.

CONCLUSIONS

Current regulatory guidelines may be insufficient if the concern is residual anti-inflammatory effects. Additionally, intra-articular corticosteroid administration is not without risk, as evidenced by a significant suppression of serum cortisol concentration and, as such, the benefits of their administration should be weighed against those risks.

Longitudinal MRI-defined Cartilage Loss and Radiographic Joint Space Narrowing Following Intra-Articular Corticosteroid Injection for Knee Osteoarthritis: A Systematic Review and Meta-analysis

Background

Intra-articular corticosteroid injections (IACS) are interventions which provide pain relief in knee osteoarthritis (OA). It remains unclear whether IACS have a deleterious effect on knee cartilage structure.

Purpose

To estimate the effect of IACS on cartilage structure in patients with knee OA, using joint space width (JSW) (in radiographic studies), and cartilage thickness (in magnetic resonance imaging).

Materials and methods

A literature search was performed to identify randomized control trials and observational studies published from inception to June 15, 2022. Studies were included if patients received IACS for knee OA, with a control arm. Given the different metrics used in reporting continuous variable outcomes among studies, pooled estimates for cartilage thickness change were assessed using standardized mean differences (defined as the difference between the means of the groups divided by a within-group standard deviation) to odds ratio transformation. Sensitivity analyses were conducted based on outcome metric, imaging modality, and number of injections.

Results

Six studies (1437 participants) were identified. The estimated effect of IACS on cartilage structure revealed greater odds of cartilage structure worsening (Odds Ratio (OR): 2.01, 95% Confidence Interval (CI): 1.18,3.44). Sensitivity analyses revealed similar trends, with significant results for singular injections with preference to JSW (OR: 2.44, 95%CI: 1.23,4.82), radiographic outcomes with preference to KL grade (OR: 2.03, 95%CI: 1.01,4.10), binary outcomes with preference to KL grade (OR: 2.93, 95%CI: 1.18,7.25) and quantitative measures (Standardized Mean Differences (SMD): -0.34, 95%CI: -0.66, -0.02).

Conclusions

IACS use may contribute to imaging features of knee cartilage loss. Further studies are warranted to investigate the underlying pathogenesis.

How safe are intra-articular corticosteroid injections to the hip?

BACKGROUND

Intra-articular corticosteroid injections (ICSI) are an effective symptomatic treatment for osteoarthritis of the hip. However, the safety of ICSI has been questioned and a relatively high risk for septic arthritis, rapidly progressive osteoarthritis (RPIO) and periprosthetic joint infections (PJI) in patients undergoing subsequent total hip arthroplasty (THA) have been suggested.

METHODS

This is a retrospective evaluation of 682 hips that underwent ICSI with 40 mg of Triamcinolone for primary osteoarthritis of the hip. All ICSI were performed using sterile techniques, the number of ICSI in each hip and the cumulative corticosteroid dosage were assessed. Pre- and post-injection radiographs were compared to identify cases with RPIO. Native joint septic arthritis, surgical site infections and PJI were identified by chart review.

RESULTS

4 hips (0.6%) developed RPIO 2-4 months following ICSI. The cumulative Triamcinolone dose was not associated with the development of RPIO (p = 0.281). 1 case was diagnosed with septic arthritis and treated with staged THA, there were no signs of infection at a 5 years follow-up. 483 hips (75.7%) underwent THA, including 199 hips with THA less than 3 months following ICSI and 181 hips with > 1 ICSI prior to THA. There were 3 superficial surgical site infections/wound dehiscence and no PJI.

CONCLUSION

The rate of RPIO was 0.6%. The current findings suggest that if ICSI is performed under sterile conditions, the risk for septic arthritis or PJI following THA, even in patients with multiple ICSI or ICSI within 3 months prior to surgery, is minimal.

In Vitro Effects of Triamcinolone and Methylprednisolone on the Viability and Mechanics of Native Articular Cartilage

BACKGROUND

The chondrotoxic effects of methylprednisolone acetate (MP) and triamcinolone acetonide (TA) have been well described. However, the mechanical effects of these commonly used steroids on native cartilage are largely unknown.

PURPOSE

To investigate the in vitro effects of a single 1-hour MP or TA exposure on the viability, mechanics, and biochemical content of native articular cartilage explants.

STUDY DESIGN

Controlled laboratory study.

METHODS

Articular cartilage explants (n = 6 per group) were harvested from the femoral condyles of bovine stifles. Explants were exposed to chondrogenic medium containing a clinical dose of MP or TA for 1 hour, followed by fresh medium wash and exchange. Explants in the control group underwent the same treatment with chondrogenic medium alone. At 24 hours after treatment, samples were assessed for viability (live/dead), mechanical properties (creep indentation and Instron tensile testing), biochemical (collagen and glycosaminoglycan) content, and pyridinoline crosslinking via mass spectrometry.

RESULTS

Mean cell viability was significantly decreased in native explants exposed to MP (35.5%) compared with the control (49.8%; P < .001) and TA (45.7%; P = .01) specimens. Significant decreases were seen in the mechanical properties of steroid-treated native explants when compared with controls, with decreases in aggregate modulus (646.3 vs 312.8 kPa [MP] and 257.0 kPa [TA]; P < .001), shear modulus (370.1 vs 191.2 kPa [MP] and 157.4 kPa [TA]; P < .001), and ultimate tensile strength (9.650 vs 5.648 MPa [MP; P = .021] and 6.065 MPa [TA; P = .0403]). No significant differences in collagen and glycosaminoglycan content were found in the steroid-treated groups. Pyridinoline crosslinking was significantly decreased in explants exposed to TA compared with controls (P = .027).

CONCLUSION

Exposure of MP to articular cartilage explants was chondrotoxic, and exposure of articular cartilage explants to MP or TA resulted in significant decreases in mechanical properties of articular cartilage explants compared with controls. Clinicians should be judicious regarding use of intra-articular steroids, particularly in patients with intact healthy articular cartilage.

Three Weekly Intra-Articular Injections of Hylan G-F 20 vs Arthrocentesis in Patients with Chronic Idiopathic Knee Osteoarthritis: A Multicenter, Evaluator- and Patient-Blinded, Randomized Controlled Trial

Background

Knee osteoarthritis is a leading cause of disability worldwide. Symptoms can vary over time, leading to episodes of worsened symptoms known as flares. Intra-articular injection of hyaluronic acid has demonstrated long-term symptomatic relief in the broader knee osteoarthritis population, although its use in the flare population has not been extensively examined.

Objective

To assess the efficacy and safety of 3 once-weekly intra-articular injections of hylan G-F 20 (as single and repeat courses) in patients with chronic knee osteoarthritis, including a subpopulation that experienced flare.

Methods

Prospective randomized controlled, evaluator- and patient-blinded, multicenter trial with 2 phases: hylan G-F 20 vs arthrocentesis only (control) and 2 courses vs single-course hylan G-F 20. Primary outcomes were visual analog scale (0-100 mm) pain scores. Secondary outcomes included safety and synovial fluid analysis.

Results

Ninety-four patients (104 knees) were enrolled in Phase I, with 31 knees representing flare patients. Seventy-six patients (82 knees) were enrolled in Phase II. Long-term follow-up was 26 to 34 weeks. In flare patients, hylan G-F 20 showed significantly more improvement than the controls for all primary outcomes except pain at night (P = 0.063). Both 1 and 2 courses of hylan G-F 20 showed significant improvements from baseline for primary outcomes with no differences in efficacy between groups in the intention-to-treat population at the end of Phase II. Two courses of hylan G-F 20 showed better improvement in pain with motion (P = 0.0471) at long-term follow-up. No general side effects were reported, and local reactions (pain/swelling of the injected joint) resolved within 1 to 2 weeks. Hylan G-F 20 was also associated with reduced effusion volume and protein concentration.

Conclusions

Hylan G-F 20 significantly improves pain scores vs arthrocentesis in flare patients with no safety concerns. A repeat course of hylan G-F 20 was found to be well tolerated and efficacious.

Extracellular vesicles in the treatment and prevention of osteoarthritis: can horses help us translate this therapy to humans?

Osteoarthritis (OA) is a common joint disease affecting humans and horses, resulting in significant morbidity, financial expense, and loss of athletic use. While the pathogenesis is incompletely understood, inflammation is considered crucial in the development and progression of the disease. Mesenchymal stromal cells (MSCs) have received increasing scientific attention for their anti-inflammatory, immunomodulatory, and pro-regenerative effects. However, there are concerns about their ability to become a commercially available therapeutic. Extracellular vesicles (EVs) are now recognized to play a crucial role in the therapeutic efficacy observed with MSCs and offer a potentially novel cell-free therapeutic that may negate many of the concerns with MSCs. There is evidence that EVs have profound anti-inflammatory, immunomodulatory, and pro-regenerative effects equal to or greater than the MSCs they are derived from in the treatment of OA. Most of these studies are in small animal models, limiting the translation of these results to humans. However, highly translational animal models are crucial for further understanding the efficacy of potential therapeutics and for close comparisons with humans. For this reason, the horse, which experiences the same gravitational impacts on joints similar to people, is a highly relevant large animal species for testing. The equine species has well-designed and validated OA models, and additionally, therapies can be further tested in naturally occurring OA to validate preclinical model testing. Therefore, the horse is a highly suitable model to increase our knowledge of the therapeutic potential of EVs.