The mechanism of action for hyaluronic acid treatment in the osteoarthritic knee: a systematic review

Treating osteoarthritis pain: mechanisms of action of acetaminophen, nonsteroidal anti-inflammatory drugs, opioids, and nerve growth factor antibodies

Osteoarthritis (OA) is a common difficult-to-treat condition where the goal, in the absence of disease-modifying treatments, is to alleviate symptoms such as pain and loss of function. Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids are common pharmacologic treatments for OA. Antibodies directed against nerve growth factor (NGF-Abs) are a new class of agents under clinical investigation for the treatment of OA. This narrative review describes (and uses schematics to visualize) nociceptive signaling, chronification of pain, and the mechanisms of action (MOAs) of these different analgesics in the context of OA-related pain pathophysiology. Further, the varying levels of efficacy and safety of these agents observed in patients with OA is examined, based on an overview of published clinical data and/or treatment guidelines (when available), in the context of differences in their MOAs.

Medium-term efficacy of arthroscopic debridement vs conservative treatment for knee osteoarthritis of Kellgren-Lawrence grades I-III

BACKGROUND

Arthroscopic debridement is a mature treatment for knee osteoarthritis (KOA). Due to the differences in the research subjects, methods, and efficacy evaluation indexes, there are great differences in the surgical efficacy reported in the literature.

AIM

To compare the medium-term efficacy of arthroscopic debridement and conservative treatment for KOA of Kellgren-Lawrence grades I-III.

METHODS

Patients with KOA of Kellgren-Lawrence grades I-III who were admitted to the orthopedic clinic of our hospital from July 2018 to December 2018 and agreed to undergo arthroscopic surgery were included in an arthroscopic debridement group, and those who refused surgical treatment were included in a conservative treatment group. Gender, age, body mass index (BMI), side of KOA, American hospital for special surgery knee score (HSS score) before treatment, visual analogue scale (VAS) score during walking and rest before treatment, conservative treatment content, and surgical procedure were recorded. Outpatient visits were conducted at the 1^st, 3^rd, 6^th, 12^th, and 24^th mo after treatment in the two groups. The changes of HSS score and VAS score in each group before and after treatment were statistically analyzed, and the differences of HSS score and VAS score in different treatment stages between the two groups were also compared.

RESULTS

In the conservative treatment group, there were 80 patients with complete follow-up data, including 20 males and 60 females, aged 58.75 ± 14.66 years old. And in the knee arthroscopic debridement group, there were 98 patients with complete follow-up data, including 24 males and 74 females, aged 59.27 ± 14.48 years old. There was no statistically significant difference in the general data (gender, age, BMI, side of KOA, Kellgren-Lawrence grade distribution, HSS score, and VAS score) between the two groups before treatment. The HSS scores of the conservative treatment group at the 1^st, 3^rd, 6^th, 12^th, and 24^th mo after treatment were significantly higher than that before treatment (P < 0.05). There was no statistical difference in HSS score of the conservative treatment group among the 1^st, 3^rd, 6^th, 12^th, and 24^th mo (P > 0.05). The HSS score of the knee arthroscopic debridement group at the 1^st mo after surgery was significantly higher than that before surgery (P < 0.05). HSS scores of the knee arthroscopic debridement group at the 3^rd, 6^th, 12^th, and 24^th mo were significantly higher than those before surgery and at the 1^st mo after surgery (P < 0.05). There were no statistically significant differences in HSS scores at the 3^rd, 6^th, 12^th, and 24^th mo after surgery (P > 0.05). HSS scores at the 3^rd, 6^th, 12^th, and 24^th mo were significantly higher in the arthroscopic debridement group than in the conservative treatment group (P < 0.05). There was no statistical difference in HSS scores between the two groups before treatment and at the 1^st mo of follow-up (P > 0.05). VAS scores during walking and rest were significantly decreased in both groups, and the VAS score during rest was significantly lower in the arthroscopic debridement group than in the conservative treatment group, but there was no significant difference in the VAS score during walking between the two groups after treatment.

CONCLUSION

Compared with conservative treatment, arthroscopic debridement can significantly improve the knee resting pain and knee functional status of patients with KOA of Kellgren-Lawrence grades I-III within 2 years after treatment.

Safety and Efficacy of an Amniotic Suspension Allograft Injection Over 12 Months in a Single-Blinded, Randomized Controlled Trial for Symptomatic Osteoarthritis of the Knee

PURPOSE

The purpose of this study is to determine the efficacy of amniotic suspension allograft (ASA) compared to hyaluronic acid (HA) and saline at up to 12 months of follow-up through the use of patient-reported outcomes, immunoglobulin levels, and anti-human leukocyte antigen (HLA) levels.

METHODS

Within this multicenter study, 200 patients were randomized 1:1:1 to a single intra-articular injection of saline, HA, or ASA. Patient-reported outcomes, including Knee Injury and Osteoarthritis Outcome Score (KOOS) and visual analog scale (VAS) score, were collected at multiple time points (baseline, 1 week, 6 weeks, 3 months, 6 months) out to 12 months to assess improvements in pain and function. Radiographs at baseline and 12 months were taken to determine radiographic changes, while blood was collected at baseline, 6 weeks, and 6 months to determine changes in immunoglobulins and anti-HLA levels. Statistical analyses were performed using last observation carried forward and mixed effects model for repeated measures.

RESULTS

Treatment with ASA resulted in significant improvements in KOOS and VAS scores that were maintained through 12 months (P < .05). Treatment with ASA resulted in a 63.2% responder rate at 12 months using the Outcome Measures in Arthritis Clinical Trials-Osteoarthritis Research Society International simplified definition. There were no significant differences between groups for radiographic measures in the index knee, immunoglobulins, C-reactive protein, or anti-HLA serum levels (P > .05). The number and type of adverse events (AEs) reported for ASA were comparable to the HA injection group, while no treatment-emergent AEs were reported for the saline group.

CONCLUSIONS

This randomized controlled trial of ASA vs HA and saline for the treatment of symptomatic knee osteoarthritis demonstrated clinically meaningful improved outcomes with ASA over the controls out to 12 months postinjection. No concerning immunologic or adverse reactions to the ASA injection were identified with regards to severe AEs, immunoglobulin, or anti-HLA levels.

LEVEL OF EVIDENCE

Level I, randomized controlled multicenter trial.

Intra-Articular Injections of Platelet-Rich Plasma, Adipose Mesenchymal Stem Cells, and Bone Marrow Mesenchymal Stem Cells Associated With Better Outcomes Than Hyaluronic Acid and Saline in Knee Osteoarthritis: A Systematic Review and Network Meta-analysis

PURPOSE

To perform a network meta-analysis to evaluate clinical efficacy and treatment-related adverse events (AEs) of intra-articular hyaluronic acid (HA), leukocyte-poor platelet-rich plasma (LP-PRP), leukocyte-rich platelet-rich plasma (LR-PRP), bone marrow mesenchymal stem cells (BM-MSCs), adipose mesenchymal stem cells (AD-MSCs), and saline (placebo) during 6 and 12 months of follow-up.

METHODS

Six databases were searched for randomized controlled trials. Outcome assessment included the visual analog scale (VAS) score, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) pain subscore, WOMAC score, International Knee Documentation Committee (IKDC) subjective score, and treatment-related AEs. Main inclusion criteria were at least one of the aforementioned outcome measurements, a minimum follow-up period of 5 months, and >80% patient follow-up. Treatments combined with the use of other operations or drugs were excluded.

RESULTS

Forty-three studies meeting the eligibility criteria were included. At 6 months, VAS scores and WOMAC pain subscores showed that AD-MSCs were the best treatment option (surface under the cumulative ranking curve [SUCRA] = 96.7%, SUCRA = 85.3%, respectively). According to WOMAC scores and subjective IKDC scores, LP-PRP was the most effective treatment (SUCRA = 86.0%, SUCRA = 80.5%, respectively). At 12 months, only AD-MSCs were associated with improved VAS scores compared with the placebo (weighted mean difference [WMD] = -20.93, 95% credibility interval [CrI], -41.71 to -0.78). Both LP-PRP and AD-MSCs were more beneficial than the placebo for improving WOMAC pain subscores (WMD = -30.08; 95% CrI, -53.59 to -6.25; WMD = -34.85; 95% CrI, -68.03 to -4.86, respectively). For WOMAC scores, LP-PRP and LR-PRP were significantly associated with improved WOMAC scores compared with the placebo after sensitivity analysis was performed (WMD = -35.26; 95% CrI, -64.99 to -6.01; WMD = -38.69; 95% CrI, -76.21 to -2.76). LP-PRP exhibited relatively better efficacy in improving subjective IKDC scores than the placebo (WMD = 13.67; 95% CrI, 4.05-23.39). Regarding safety, all treatments except for LP-PRP (relative risk = 1.83; 95% CrI, 0.89-4.64) increased treatment-related AEs compared with the placebo.

CONCLUSIONS

Based on the results of current research findings, during 6 months of follow-up, AD-MSCs relieved pain the best; LP-PRP was most effective for functional improvement. During the 12-month follow-up, both AD-MSCs and LP-PRP showed potential clinical pain relief effects; functional improvement was achieved with LP-PRP. Unfortunately, AD-MSC/LP-PRP functional comparisons were only based on WOMAC scores due to missing IKDC scores. BM-MSCs seem to have potentially beneficial effects, but the wide credibility interval makes it impossible to draw a well-supported conclusion. HA viscosupplementation clinical efficacy was lower than that of biological agents during follow-up, which may be related to the properties of the drugs. Considering the evaluation of treatment-related AEs, LP-PRP is the most advisable choice; although the AEs of these treatments are not serious, they may affect treatment compliance and satisfaction.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

Safety and efficacy of single CHAP Hyaluronan injection versus three injections of linear Hyaluronan in pain relief for knee osteoarthritis: a prospective, 52-week follow-up, randomized, evaluator-blinded study

Background

The hyaluronic acid (HA) injections are widely used in knee osteoarthritis (OA) patients. We conducted the study comparing the efficacy and safety of single injection of Crosslinked Hyaluronic Acid Platform Hyaluronan (CHAP-HA) with 3-injection of linear hyaluronan in knee OA patients.

Methods

This was a randomized two-arms, evaluator-blinded, controlled, single-center study. Participants with knee OA received single CHAP-HA or three-injection of linear-HA. The 140 patients aged 35–85 years with radiographically confirmed knee OA were enrolled. At week 4, 12, 26, 39, and 52, visual analog scale (VAS) pain score, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index, timed up and go (TUG) and subject’s adverse events (AE) of these 2 groups were recorded. Primary outcome of the differences of VAS pain score at week 26 between groups was analyzed with analysis of covariance (ANCOVA). At week 52, those who met the inclusion criteria could receive a CHAP-HA injection and being followed-up for the adverse events for 4 weeks.

Results

The trial was conducted from September 2015 to April 2017. A total 140 subjects were available for analysis (71 in the CHAP-HA group and 69 in the linear-HA group). At 26th week, there were significant more improvements in VAS pain scores in CHAP-HA compared with linear-HA. Both CHAP-HA and linear-HA showed significant improvements in the VAS pain score at week 26 compared with the baseline, and the occurrence of adverse events during the study period showed no between-group difference. In subjects with KL = 2, both groups showed significant improvements in VAS pain scores within 26 weeks. In patients with KL = 3, only CHAP-HA group showed significant improvement in VAS pain from 4 to 39 weeks. No unexpected or severe AEs were reported.

Conclusions

A single injection of CHAP-HA may be safe and more effective for 26 weeks in patients with knee OA by comparing to linear-HA; moreover, the pain relief effect of CHAP-HA may remain until 52 weeks. For patients with more severe OA, CHAP-HA was demonstrated to be more preferable to relieve OA pain. Furthermore, repeat treatment of CHAP-HA or using CHAP-HA after a three-injection HA was proved to be safe.

Trial registration

ClinicalTrials.gov: NCT03643588. Date: August 23, 2018 (retrospectively registered).

Level of Evidence: Therapeutic Level I.

Insights from Real-World Analysis of Treatment Patterns in Patients with Newly Diagnosed Knee Osteoarthritis

BACKGROUND

Several nonpharmacologic and pharmacologic treatments are available for the management of knee osteoarthritis (OA)-related pain and for improving functionality; however, clinical guideline recommendations vary on their use.

OBJECTIVE

To compare the treatment patterns in a real-world setting versus the guideline recommendations for the treatment of newly diagnosed patients with knee OA.

METHODS

This retrospective analysis used data from the electronic health records of the Geisinger Health System between January 1, 2010, and December 2018 to identify adults with newly diagnosed knee OA who had not received previous therapy with intra-articular corticosteroids, opioids, intra-articular hyaluronic acid, or prescription nonsteroidal anti-inflammatory drugs (NSAIDs). Eligible patients were evaluated for the mutually exclusive treatment categories after diagnosis, including prescription NSAIDs, intra-articular corticosteroids, intra-articular hyaluronic acid (specifically an intra-articular bioengineered hyaluronic acid), opioids, physical therapy, bracing, and total knee arthroplasty. These 7 treatment categories were evaluated for utilization patterns in the real-world setting.

RESULTS

A total of 8776 patients with a new diagnosis of knee OA were identified; 88.2% of them received 1 of the 7 evaluated treatments. The most frequently prescribed first treatment was intra-articular corticosteroids (26%), followed by opioids (17.6%), and intra-articular bioengineered hyaluronic acid (14.9%). The most often prescribed second treatment was opioids (15.8%), followed by physical therapy (14%), NSAIDs (11.8%), and intra-articular bioengineered hyaluronic acid (9.6%). Of note, 22.9% of the patients received only 1 evaluated therapy during the study period and did not receive a second treatment.

CONCLUSIONS

Real-world treatment patterns in patients with newly diagnosed knee OA indicate that prescribers are using the spectrum of the available therapies that, at times, are different from the current treatment guideline recommendations.

Viscosupplementation for the treatment of osteoarthritis. The contribution of EUROVISCO group

Viscosupplementation (VS) is a symptomatic treatment for knee and other joint osteoarthritis (OA). Despite a long history of use, conflicting opinions remain on the best clinical indications and the most appropriate patients to be treated with intra-articular hyaluronic acid (IA-HA), the optimal dosing regimen and the modalities of retreatment. A multidisciplinary committee of European experts on OA (EUROVISCO) was constituted to formulate recommendations, aimed at helping physicians in the decision-making and the optimal achievement of VS. Before each session members were tasked to collate an exhaustive literature review. Level of evidence and strength of recommendation were based on the level of agreement for each item according to the Delphi method. In 2015, a consensus position was proposed for 24 statements. Among those that obtained a consensual agreement, the working group stressed that VS is effective in mild/moderate knee OA but is not an alternative to surgery in advanced OA, and that dosing regimen must be supported by controlled trials. In 2018, two decision algorithms for the retreatment with IA-HA in knee OA were published. Among the key recommendations, the experts recommended to re-treat every year patients with high risk of OA progression, even if not symptomatic. In 2020, EUROVISCO published two sets of recommendations for the design of clinical trials on the disease-modifying effect of VS and for optimizing the results of VS. The working group underlined that an accurate analysis of radiological features and symptoms and a careful clinical examination may improve the chances of success of VS, as well as good technique of injection and the use of imaging guidance. Based on the exhaustive analysis of the literature and their own clinical experience, the EUROVISCO experts offer a wide range of recommendations intended to help practitioners, particularly in certain cases where the specific characteristics of the patients make the therapeutic decision difficult.

Hamid MS. Efficacy of prolotherapy in comparison to other therapies for chronic soft tissue injuries: A systematic review and network meta-analysis

Introduction

Prolotherapy and other injections, primarily acting on pathways associated with maladaptive tissue repair, are recommended for recalcitrant chronic soft tissue injuries (CSTI). However, selection of injection is challenging due to mixed results. This network meta-analysis (NMA) aimed to compare prolotherapy with other therapies, particularly injections, for CSTI and establish robustness of the results.

Methodology

Pubmed, Medline, SPORTDiscus and Google scholar were searched from inception to 4^th January 2021 for randomised controlled trials (RCTs) involving injection therapies (e.g. blood derivatives, corticosteroid, hyaluronic acid, botulinum toxin) for CSTI. The primary and secondary outcomes were pain and function, respectively, at (or nearest to) 6 months. Effect size (ES) was presented as standardised mean difference with 95% confidence interval (CI). Frequentist random effect NMA was used to generate the overall estimates, subgroup estimates (by region and measurement time point) and sensitivity analyses.

Results

A total of 91 articles (87 RCTs; 5859 participants) involving upper limb (74%), lower limb (23%) and truncal/hip (3%) injuries were included. At all time points, prolotherapy had no statistically significant pain benefits over other therapies. This observation remained unchanged when tested under various assumptions and with exclusion of studies with high risk of bias. Although prolotherapy did not offer statistically significant functional improvement compared to most therapies, its ES was consistently better than non-injections and corticosteroid injection for both outcomes. At selected time points and for selected injuries, prolotherapy demonstrated potentially better pain improvement over placebo (<4 months: shoulder [ES 0.65; 95% CI 0.00 to 1.30]; 4–8 months: elbow [ES 0.91; 95% CI 0.12 to 1.70]; >8 months: shoulder [ES 2.08; 95% CI 1.49, to 2.68]). Injections generally produced greater ES when combined with non-injection therapy.

Conclusion

While clinical outcomes were generally comparable across types of injection therapy, prolotherapy may be used preferentially for selected conditions at selected times.

Changes in levels of cartilage oligomeric proteinase and urinary C-terminal telopeptide of type II collagen in subjects with knee osteoarthritis after dextrose prolotherapy: A randomized controlled trial

OBJECTIVE

To assess the effects of dextrose prolotherapy in patients with knee osteoarthritis on the levels of serum cartilage oligomeric proteinase and urinary C-terminal telopeptide of type II collagen, and on the Western Ontario McMaster Universities Index and numerical rating scale score for pain.

METHODS

A randomized controlled trial, in which participants were randomly allocated into 2 groups, receiving injections of either hyaluronic acid or dextrose prolotherapy. The hyaluronic acid group received 5 injections, 1 each on weeks 1, 2, 3, 4 and 5, and the dextrose prolotherapy group received 3 injections, 1 each on weeks 1, 5 and 9. Serum cartilage oligomeric proteinase, urinary C-terminal telopeptide of type II collagen, Western Ontario McMaster Universities Index score, and numerical rating scale score for pain were measured at baseline and 3 weeks after the last injection. Comparative analysis was conducted using Wilcoxon test within groups and analysis of covariance (ANCOVA) test between groups.

RESULTS

A total of 47 participants (21 allocated to hyaluronic acid, 26 allocated to dextrose prolotherapy) completed the protocol. Both interventions resulted in significant improvements in numerical rating scale scores for pain, total Western Ontario McMaster Universities Index scores, and its subscales score. However, the dextrose prolotherapy outperformed hyaluronic acid in numerical rating scale score for pain and level of urinary C-terminal telopeptide of type II collagen, with score changes differences of 0.93 (p = 0.042) and 0.34 (p = 0.048), respectively. No significant changes in level of serum cartilage oligomeric proteinase were found in either group.

CONCLUSION

Dextrose prolotherapy is an alternative injection therapy for knee osteoarthritis, which was found to be associated with a significant reduction in urinary C-terminal telopeptide of type II collagen compared with hyaluronic acid injection. Neither injection method resulted in reduced serum cartilage oligomeric proteinase.

Diacerein-Loaded Hyaluosomes as a Dual-Function Platform for Osteoarthritis Management via Intra-Articular Injection: In Vitro Characterization and In Vivo Assessment in a Rat Model

The application of intra-articular injections in osteoarthritis management has gained great attention lately. In this work, novel intra-articular injectable hyaluronic acid gel-core vesicles (hyaluosomes) loaded with diacerein (DCN), a structural modifying osteoarthritis drug, were developed. A full factorial design was employed to study the effect of different formulation parameters on the drug entrapment efficiency, particle size, and zeta potential. Results showed that the prepared optimized DCN- loaded hyaluosomes were able to achieve high entrapment (90.7%) with a small size (310 nm). The morphology of the optimized hyaluosomes was further examined using TEM, and revealed spherical shaped vesicles with hyaluronic acid in the core. Furthermore, the ability of the prepared DCN-loaded hyaluosomes to improve the in vivo inflammatory condition, and deterioration of cartilage in rats (injected with antigen to induce arthritis) following intra-articular injection was assessed, and revealed superior function on preventing cartilage damage, and inflammation. The inflammatory activity assessed by measuring the rat’s plasma TNF-α and IL-1b levels, revealed significant elevation in the untreated group as compared to the treated groups. The obtained results show that the prepared DCN-loaded hyaluosomes would represent a step forward in the design of novel intra articular injection for management of osteoarthritis.

The role of viscosupplementation in patellar chondropathy

Patellar chondropathy has a high incidence in the general population, being more common in patients younger than 50 years, female and recreational athletes, and overweight and obese patients. The most common complaints are pain, limited mobility, crepitus, difficulty climbing and descending stairs, and joint instability, usually showing unsatisfactory results with anti-inflammatory, physiotherapy, rehabilitation, and many other conservative treatment methods. The presumed hyaluronic acid (HA) disease-modifying activity may include effects on cartilage degradation, endogenous HA synthesis, synoviocyte and chondrocyte function, and other cellular inflammatory processes. Currently, HA is widely used as a safe and effective conservative treatment for osteoarthritis in the knee and other joints. HA improves the physiological environment in an osteoarthritic joint and the shock absorption and lubrication properties of the osteoarthritic synovial fluid, thus restoring the protective viscoelasticity of the synovial HA, reducing the pain, and improving the mobility. The complete mechanism of HA in the joint is not fully understood, but a wide range of actions in the joint is recognized. Its anti-inflammatory, analgesic, and chondroprotective action is related to the modulation of the intra- and extracellular inflammation cascade. HA has been shown to be safe and effective in the treatment of pain related to patellar chondropathy.

Efficacy and safety of a single intra-articular injection of 6 ml Hylan G-F 20 compared to placebo in Chinese patients with symptomatic knee osteoarthritis : C-SOUND study, a 26-week multicenter double-blind randomized placebo-controlled trial in China

BACKGROUND

Single 6 ml Hylan G-F 20 injection, is indicated for knee osteoarthritis patients who have failed to respond to non-pharmacologic therapy and/or simple analgesics. To obtain more thorough understanding of the clinical efficacy and safety, a randomized clinical trial was conducted comparing intra-articular (IA) administration of single 6 ml Hylan G-F 20 injection versus placebo in knee OA patients of Chinese ethnicity.

METHODS

This was a randomized, multi-center, double-blind, placebo-controlled clinical trial conducted in 21 centers across China. Four hundred forty adults with knee OA received a single 6 ml Hylan G-F 20 or placebo injection and were evaluated for clinical efficacy and safety outcomes over 26 weeks. Western Ontario and McMaster Universities OA (WOMAC) A1 index, treatment-emergent adverse events (TEAEs) and standard safety parameters were measured at pre-injection, and at weeks 1, 4, 8, 12, 16, 20 and 26 post-injection.

RESULTS

Four hundred forty patients (male: 98 [22.3%]; female: 342 [77.7%]) were randomized. The mean age [standard deviation (SD)] was 61.5 (7.9) years. All patients were of East Asian ethnicity. Mean WOMAC A1 score at baseline was 5.3 (1.2) and 5.2 (1.3) in single 6 ml Hylan G-F 20 injection and placebo groups, respectively. Significant reductions of WOMAC A1 score were observed in both treatment groups when compared to baseline at 26 weeks post-injection, with the mean reduction of [standard error (SE)/percentage] -2.146 (0.108)/- 40.5% and - 2.271 (0.110) /- 43.7% in the single 6 ml Hylan G-F 20 injection and the placebo groups, respectively. Additionally, clinically important reductions in pain at 26 weeks was reported in 67.0 and 68.2% in single 6 ml Hylan G-F 20 injection and placebo groups (p = 0.36). Regarding safety, TEAEs were similar between the two treatment groups (hylan G-F 20 single: 61.5%; placebo: 64.5%).

CONCLUSIONS

While the magnitude of the effect of a single 6 ml Hylan G-F 20 injection in this study is consistent with previously published literature with respect to the efficacy and safety of the drug, the current study shows a strong IA placebo effect and did not established superiority of single 6 ml Hylan G-F 20 injection over IA placebo in Chinese knee OA patients.

TRIAL REGISTRATION

Prospectively registered Jun 16, 2017 at www.clinicaltrials.gov ( NCT03190369 ).

Treatment Efficacy with a Novel Hyaluronic Acid-Based Hydrogel for Osteoarthritis of the Knee

Background: Prior trials investigating the treatment of symptomatic osteoarthritis (OA) with hyaluronic-acid-derived products injections have provided optimistic results. The study was directed to assess the effectiveness of an innovative hyaluronic-acid-based hydrogel (Hymovis^®) in the treatment of symptomatic knee OA. Methods: A prospective, single-center, clinical trial was performed. Thirty-five patients with degenerative knee OA were included. Inclusion criteria were: age between 45–80, radiographic Kellgren grade II or III osteoarthritis, minimum 35 mm score on the Visual Analogue Scale (VAS), pain for at least 6 months and agreement to participate in the study. Patients received two injections at a one-week interval. The evaluator assessed the patients using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and VAS. Evaluation was performed before, at 2 and 6 months after the injections. Results: A significant improvement on the WOMAC Index pain subscale was observed at 6 months after the injection. At two months, pain subscale score decreased from 10.34 to 9.34. At six months, a significant decrement in pain parameters compared to baseline was observed (from 10.34 to 7.72; p = 0.0004). Median points on VAS significantly ameliorated after 6 months (from 74.2 to 57.3 cm; p < 0.0001). Regarding physical function, a statistically significant difference compared to baseline was observed at the end of the study (from 29.74 to 25.18; p = 0.0025). WOMAC Index stiffness component did not differ from baseline at any time during follow-up. Conclusions: Pain relief installed with a delayed on-set but had a prolonged duration. The novel hyaluronic acid-based hydrogel (Hymovis^®) had effective results, particularly after six months post-injections and offers a therapeutic advancement in the treatment of moderate to severe osteoarthritis.

Immunomodulatory biomaterials and their application in therapies for chronic inflammation-related diseases

The degree of tissue injuries such as the level of scarring or organ dysfunction, and the immune response against them primarily determine the outcome and speed of healing process. The successful regeneration of functional tissues requires proper modulation of inflammation-producing immune cells and bioactive factors existing in the damaged microenvironment. In the tissue repair and regeneration processes, different types of biomaterials are implanted either alone or by combined with other bioactive factors, which will interact with the immune systems including immune cells, cytokines and chemokines etc. to achieve different results highly depending on this interplay. In this review article, the influences of different types of biomaterials such as nanoparticles, hydrogels and scaffolds on the immune cells and the modification of immune-responsive factors such as reactive oxygen species (ROS), cytokines, chemokines, enzymes, and metalloproteinases in tissue microenvironment are summarized. In addition, the recent advances of immune-responsive biomaterials in therapy of inflammation-associated diseases such as myocardial infarction, spinal cord injury, osteoarthritis, inflammatory bowel disease and diabetic ulcer are discussed.

Polymer particles for the intra-articular delivery of drugs to treat osteoarthritis

Osteoarthritis (OA) is a leading cause of chronic disability. It is a progressive disease, involving pathological changes to the entire joint, resulting in joint pain, stiffness, swelling, and loss of mobility. There is currently no disease-modifying pharmaceutical treatment for OA, and the treatments that do exist suffer from significant side effects. An increasing understanding of the molecular pathways involved in OA is leading to many potential drug targets. However, both current and new therapies can benefit from a targeted approach that delivers drugs selectively to joints at therapeutic concentrations, while limiting systemic exposure to the drugs. Delivery systems including hydrogels, liposomes, and various types of particles have been explored for intra-articular drug delivery. This review will describe progress over the past several years in the development of polymer-based particles for OA treatment, as well as their in vitro, in vivo, and clinical evaluation. Systems based on biopolymers such as polysaccharides and polypeptides, as well as synthetic polyesters, poly(ester amide)s, thermoresponsive polymers, poly(vinyl alcohol), amphiphilic polymers, and dendrimers will be described. We will discuss the role of particle size, biodegradability, and mechanical properties in the behavior of the particles in the joint, and the challenges to be addressed in future research.

In Vivo Cartilage Regeneration with Cell-Seeded Natural Biomaterial Scaffold Implants: 15-Year Study

Articular cartilage can be easily damaged from human's daily activities, leading to inflammation and to osteoarthritis, a situation that can diminish the patients' quality of life. For larger cartilage defects, scaffolds are employed to provide cells the appropriate three-dimensional environment to proliferate and differentiate into healthy cartilage tissue. Natural biomaterials used as scaffolds, attract researchers' interest because of their relative nontoxic nature, their abundance as natural products, their easy combination with other materials, and the relative easiness to establish Marketing Authorization. The last 15 years were chosen to review, document, and elucidate the developments on cell-seeded natural biomaterials for articular cartilage treatment in vivo. The parameters of the experimental designs and their results were all documented and presented. Considerations about the newly formed cartilage and the treatment of cartilage defects were discussed, along with difficulties arising when applying natural materials, research limitations, and tissue engineering approaches for hyaline cartilage regeneration.

Comprehensive Review of Knee Osteoarthritis Pharmacological Treatment and the Latest Professional Societies' Guidelines

Osteoarthritis is the most common musculoskeletal progressive disease, with the knee as the most commonly affected joint in the human body. While several new medications are still under research, many symptomatic therapy options, such as analgesics (opioid and non-opioid), nonsteroid anti-inflammatory drugs, symptomatic slow-acting drugs in osteoarthritis, and preparations for topical administration, are being used, with a diverse clinical response and inconsistent conclusions across various professional societies guidelines. The concept of pharmacogenomic-guided therapy, which lies on principles of the right medication for the right patient in the right dose at the right time, can significantly increase the patient's response to symptom relief therapy in knee osteoarthritis. Corticosteroid intra-articular injections and hyaluronic acid injections provoke numerous discussions and disagreements among different guidelines, even though they are currently used in daily clinical practice. Biological options, such as platelet-rich plasma and mesenchymal stem cell injections, have shown good results in the treatment of osteoarthritis symptoms, greatly increasing the patient's quality of life, especially when combined with other therapeutic options. Non-inclusion of the latter therapies in the guidelines, and their inconsistent stance on numerous therapy options, requires larger and well-designed studies to examine the true effects of these therapies and update the existing guidelines.

Shoulder injections with autologous conditioned serum reduce pain and disability in glenohumeral osteoarthritis: longitudinal observational study

BACKGROUND

Currently, non-surgical treatments for glenohumeral osteoarthritis (GH-OA) mainly aim to reduce pain. Autologous conditioned serum (ACS), Orthokine, an interleukin-1 inhibitor from the patient's own blood has an anti-inflammatory effect. The objective was to determine whether intra-articular injections of this ACS improved symptoms in patients with GH-OA and delayed the need for a shoulder replacement.

METHODS

A total of 36 consecutive patients, 40 shoulders, with OA received up to 6-weekly intra-articular injections of ACS were included. Imaging of GH-OA, range of motion, visual analogue scale (VAS) pain, Shoulder Pain And Disability Index (SPADI), American Shoulder and Elbow Surgeons and Constant scores were assessed pre-injection and post treatment at 3 months. At a minimum of 2 years, VAS and SPADI scores and whether anyone had progressed to a shoulder replacement were recorded.

RESULTS

Outcomes 3 months post-ACS injections demonstrated on average statistically significant improvement (P < 0.05) of all measurements: SPADI (54.3 ± 21.5 vs 43.7 ± 23.7), Constant score (50.5 ± 14.1 vs 57.1 ± 17.4), VAS pain (4.8 ± 2.2 vs 3.7 ± 2.4) and range of motion. Of these, 16 shoulders progressed to a shoulder replacement, nine cases quickly (0.6 ± 0.2 years) and seven cases were delayed by 3.1 ± 1.7 years. The other 18 cases had significant improvement in pain, SPADI (58.0 ± 19.6 to 31.8 ± 21.4; P < 0.01) scores and no progression to a shoulder replacement at 3.6 ± 1.0 years follow-up. There was no correlation of glenoid Walch score or joint space with clinical outcome parameters.

CONCLUSION

ACS injections in the shoulder joint for OA can reduce pain and disability, and postpone the need for a shoulder replacement.

Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Platelet-rich plasma (PRP) and hyaluronic acid (HA) are 2 nonoperative treatment options for knee osteoarthritis (OA) that are supposed to provide symptomatic relief and help delay surgical intervention.

PURPOSE

To systematically review the literature to compare the efficacy and safety of PRP and HA injections for the treatment of knee OA.

STUDY DESIGN

Meta-analysis of level 1 studies.

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify level 1 studies that compared the clinical efficacy of PRP and HA injections for knee OA. The search phrase used was platelet-rich plasma hyaluronic acid knee osteoarthritis randomized. Patients were assessed via the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) scale. A subanalysis was also performed to isolate results from patients who received leukocyte-poor and leukocyte-rich PRP.

RESULTS

A total of 18 studies (all level 1) met inclusion criteria, including 811 patients undergoing intra-articular injection with PRP (mean age, 57.6 years) and 797 patients with HA (mean age, 59.3 years). The mean follow-up was 11.1 months for both groups. Mean improvement was significantly higher in the PRP group (44.7%) than the HA group (12.6%) for WOMAC total scores (P < .01). Of 11 studies based on the VAS, 6 reported PRP patients to have significantly less pain at latest follow-up when compared with HA patients (P < .05). Of 6 studies based on the Subjective IKDC outcome score, 3 reported PRP patients to have significantly better scores at latest follow-up when compared with HA patients (P < .05). Finally, leukocyte-poor PRP was associated with significantly better Subjective IKDC scores versus leukocyte-rich PRP (P < .05).

CONCLUSION

Patients undergoing treatment for knee OA with PRP can be expected to experience improved clinical outcomes when compared with HA. Additionally, leukocyte-poor PRP may be a superior line of treatment for knee OA over leukocyte-rich PRP, although further studies are needed that directly compare leukocyte content in PRP injections for treatment of knee OA.

Differential characteristics and management of pseudoseptic arthritis following hyaluronic acid injection is a rare complication: a systematic review

IMPORTANCE

Acute pseudoseptic arthritis is a rare complication of hyaluronic acid (HA) injections that is not well documented in the literature. Practitioners initially suspect the symptoms of this complication to represent septic arthritis, cautiously prescribing antibiotics. This review identifies that time to presentation of symptoms postinjection, negative cell cultures and lack of crystallisation could be used as differentials to suspect pseudoseptic arthritis and to prescribe anti-inflammatory drugs while closely monitoring change of symptoms.

OBJECTIVE

The purpose of this study was to describe the presentation, diagnosis and treatment of pseudoseptic arthritis.

EVIDENCE REVIEW

A systematic review of the literature was conducted for studies reporting the use of HA injections for osteoarthritis resulting in pseudoseptic arthritis using the electronic databases MEDLINE, Embase and PubMed. Pertinent data were abstracted from the search yield. A unique case of a pseudoseptic reaction is also presented.

FINDINGS

A total of 11 studies (28 cases), all of level IV and V evidence were included in this review. Reported cases of pseudoseptic arthritis in the literature present with severe joint pain (100%), effusion (100%), inability to weight-bear, functional impairment, and occasionally fever (22.2%). C reactive protein and erythrocyte sedimentation rate are generally elevated (71.4% and 85.7%, respectively), and leucocytosis above 10 000 was less common (50%). All reported cases in the literature identified aseptic growth on arthrocentesis, despite four cases (15.4%) reporting synovial leucocyte counts above 50 000. The presented case is the highest reported leucocyte count at 1 74 960 cells/mm³.

CONCLUSIONS AND RELEVANCE

Acute pseudoseptic arthritis is rare, but a number of cases have been reported in the literature. A high degree of suspicion for pseudoseptic arthritis may be maintained in patients who present under 72 hours following HA injection. Initial antibiotic treatment, along with anti-inflammatory medications until cultures are confirmed to be negative at 5 days, is a cautious approach. However, the strength of this conclusion is limited by the few reported cases. Ultimately, this review is intended to inform practitioners of the symptoms, diagnosis and treatment of this complication, such that it could be safely differentiated from septic arthritis.

LEVEL OF EVIDENCE

IV.

Decrease in opioid and intra-articular corticosteroid burden after intra-articular hyaluronic acid for knee osteoarthritis treatment

Aim: We studied changes in opioid prescriptions and corticosteroid injection use for knee osteoarthritis patients before and after intra-articular hyaluronic acid (HA) use and opioid prescriptions before and after knee arthroplasty (KA). Materials & methods: A total of 1,017,578 knee osteoarthritis members were ascertained from a commercial claims database (Health Intelligence Company LLC, IL, USA) using ICD9/ICD10 diagnosis codes. Results: Eighty two percent of HA patients did not fill opioid prescriptions postinjection, with 54% of opioid users discontinuing fills. Two-thirds of KA patients filled opioid prescriptions within 6 months postsurgery, with 78% of opioid users continuing fills and 62% of nonusers initiating use. Conclusion: Alternative therapies, such as HA, that reduce opioid use may alleviate opioid addiction risks for KA patients who use opioids in the pre- and postoperative periods.

Duloxetine combined with intra-articular injection versus intra-articular injection alone for pain relief in knee osteoarthritis: a study protocol for a randomised controlled trial

INTRODUCTION

Intra-articular (IA) injection of hyaluronic acid (HA) and corticosteroid (CS) is a common treatment for osteoarthritis (OA) of the knee. As a drug treatment for patients with depression, duloxetine has been shown in many studies to effectively relieve the pain of OA and improve function of the knee joint. However, evidence regarding the efficacy of IA injection of HA+CS combined with duloxetine for pain management in patients with OA of the knee is lacking. The aim of this study was to test the hypothesis that IA injection of HA+CS combined with duloxetine could achieve pain management superior to that of IA injection of HA+CS alone in patients experiencing knee OA pain.

METHODS

This study will adopt a prospective, randomised, open-label blind endpoint study design. In total, 150 patients with OA of the knee will be enrolled in the study. The participants will be randomly allocated to receive either a single IA injection of HA+CS combined with duloxetine or a single IA injection of HA+CS alone, and both groups will complete a 24-week follow-up to assess pain and functional improvements. The primary outcome measure is the change in the weekly mean of the 24 hours average pain scores from baseline to the end of 24 weeks in patients with OA of the knee, and the secondary outcomes include the response to treatment, changes from baseline in the brief pain inventory, improvement in the Western Ontario and McMaster Universities Osteoarthritis index scores, patient global impression of improvement scale, Hospital Anxiety and Depression Scale and adverse events during the 24-week follow-up. The data will be analysed by the intention-to-treat principle.

ETHICS APPROVAL AND DISSEMINATION

This study was approved by the institutional ethics committee of the Beijing Tiantan Hospital (approval number: KY 2019-086-02). The results of the study will be published in peer-reviewed journals, and the findings will be presented at scientific meetings.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT04117893; Pre-results.

High molecular weight Intraarticular hyaluronic acid for the treatment of knee osteoarthritis: a network meta-analysis

BACKGROUND

The 2013 American Academy of Orthopaedic Surgeons (AAOS) guidelines made strong recommendations against intraarticular hyaluronic acid (IAHA) for patients with knee osteoarthritis (OA), as evidence supporting improvements in pain did not meet the minimal clinically important improvement (MCII) threshold. However, there may be important distinctions based on IAHA molecular weight (MW). Hence our objective was to evaluate the efficacy of IAHAs in knee OA based on molecular weight.

METHODS

Randomized controlled trials were searched within MEDLINE, Embase, and CENTRAL and selected based on AAOS criteria. A pain measure hierarchy and longest follow-up were used to select one effect size from each trial. Mean differences between interventions were converted to standardized mean differences (SMDs) and incorporated into a random-effects Bayesian network meta-analysis. High MW (HMW) was defined as ≥6000 kDa, and low MW (LMW) as < 750 kDa.

RESULTS

HMW IAHA was associated with a statistically significant and possibly clinically significant improvement in pain (SMD - 0.57 (95% credible interval [Crl]: - 1.04, - 0.11), exceeding the - 0.50 MCII threshold. LMW IAHA had a lesser, non-significant improvement (- 0.23, 95% Crl: - 0.67, 0.20). Back-transforming SMDs to the WOMAC pain scale indicated a 14.65 (95% CI: 13.93, 15.62) point improvement over IA placebo, substantially better than the 8.3 AAOS MCII threshold.

CONCLUSIONS

Unlike LMW IAHA, HMW IAHA exceeded the MCII threshold for pain relief, suggesting that improvements can be subjectively perceived by the treated patient. Amalgamation of LMW and HMW may have blurred the benefits of IAHA in the past, leading to negative recommendations. Differentiation according to MW offers refined insight for treatment with IAHA.

Effects of Hyaluronan Molecular Weight on the Lubrication of Cartilage-Emulating Boundary Layers

Osteoarthritic joints contain lower-molecular-weight (MW) hyaluronan (hyaluronic acid, HA) than healthy joints. To understand the relevance of this HA size effect for joint lubrication, the friction and surface structure of cartilage-emulating surfaces with HA of different MWs were studied using a surface force balance (SFB) and atomic force microscopy (AFM). Gelatin (gel)-covered mica surfaces were coated with high-MW HA (HHA), medium-MW HA (MHA), or low-MW HA (LHA), and lipids of hydrogenated soy l-α-phosphatidylcholine (HSPC) in the form of small unilamellar vesicles, using a layer-by-layer assembly method. SFB results indicate that the gel-HHA-HSPC boundary layer provides very efficient lubrication, attributed to hydration lubrication at the phosphocholine headgroups exposed by the HA-attached lipids, with friction coefficients (COF) as low as 10-3-10-4 at contact stresses at least up to P = 120 atm. However, for the gel-MHA-HSPC and gel-LHA-HSPC surfaces, the friction, initially low, increases sharply at much lower pressures (up to 30-60 atm at most). This higher friction with the shorter chains may be due to their weaker total adhesion energy to the gelatin, where the attraction between the negatively charged HA and the weakly positively charged gelatin is attributed largely to counterion-release entropy. Thus, the complexes of LHA and MHA with the lubricating HSPC lipids are more easily removed by shear during sliding, especially at high stresses, than the HHA-HSPC complex, which is strongly adhered to gelatin. This is ultimately the reason for lower-pressure lubrication breakdown with the shorter polysaccharides. Our results provide molecular-level insight into why the decrease in HA molecular weight in osteoarthritic joints may be associated with higher friction at the articular cartilage surface, and may have relevance for treatments of osteoarthritis involving intra-articular HA injections.

Short-term outcomes after pure bone marrow aspirate injection for severe knee osteoarthritis: a case series

Background: Bone marrow aspiration (BMA) is among a group of autologous cell-based therapies currently being explored to treat osteoarthritis (OA). Materials & methods: This retrospective case study observed ten patients (13 knees) with severe knee OA who failed extensive conservative treatment and were treated with BMA injection using a novel, pure bone marrow aspiration (pBMA) technique. Results: No adverse events were reported. More than 50% reduction in the visual analog scale score for pain was observed at 2- and 12-weeks post-procedure, showing statistical significance. At 64 ± 26 weeks post-procedure, average knee pain remained significantly less than pre-procedure. Conclusion: Therefore, patients with severe knee OA may achieve significant relief after a BMA injection obtained using this pure bone marrow aspiration technique.

Cooled Radiofrequency Ablation Compared with a Single Injection of Hyaluronic Acid for Chronic Knee Pain: A Multicenter, Randomized Clinical Trial Demonstrating Greater Efficacy and Equivalent Safety for Cooled Radiofrequency Ablation

BACKGROUND

Knee osteoarthritis is a painful and sometimes debilitating disease that often affects patients for years. Current treatments include short-lasting and often repetitive nonsurgical options, followed by surgical intervention for appropriate candidates. Cooled radiofrequency ablation (CRFA) is a minimally invasive procedure for the treatment of pain related to knee osteoarthritis. This trial compared the efficacy and safety of CRFA with those of a single hyaluronic acid (HA) injection.

METHODS

Two hundred and sixty subjects with knee osteoarthritis pain that was inadequately responsive to prior nonoperative modalities were screened for enrollment in this multicenter, randomized trial. One hundred and eighty-two subjects who met the inclusion criteria underwent diagnostic block injections and those with a minimum of 50% pain relief were randomized to receive either CRFA on 4 genicular nerves or a single HA injection. One hundred and seventy-five subjects were treated (88 with CRFA and 87 with HA). Evaluations for pain (Numeric Rating Scale [NRS]), function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), quality of life (Global Perceived Effect [GPE] score and EuroQol-5 Dimensions-5 Level [EQ-5D-5L] questionnaire), and safety were performed at 1, 3, and 6 months after treatment.

RESULTS

Demographic characteristics did not differ significantly between the 2 study groups. A total of 158 subjects (76 in the CRFA group and 82 in the HA group) completed the 6-month post-treatment follow-up. In the CRFA group, 71% of the subjects had ≥50% reduction in the NRS pain score (primary end point) compared with 38% in the HA group (p < 0.0001). At 6 months, the mean NRS score reduction was 4.1 ± 2.2 for the CRFA group compared with 2.5 ± 2.5 for the HA group (p < 0.0001). The mean WOMAC score improvement at 6 months from baseline was 48.2% in the CRFA group and 22.6% in the HA group (p < 0.0001). At 6 months, 72% of the subjects in the CRFA group reported improvement in the GPE score compared with 40% in the HA group (p < 0.0001).

CONCLUSIONS

CRFA-treated subjects demonstrated a significant improvement in pain relief and overall function compared with subjects treated with a single injection of HA. No serious adverse events related to either procedure were noted, and the overall adverse-event profiles were similar.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of single high-molecular-weight versus triple low-molecular-weight hyaluronic acid intra-articular injection among knee osteoarthritis patients

Background

To compare intra-articular (IA) knee injections of a cross-linked high-molecular-weight hyaluronic acid (HMW-HA) with a linear low-molecular weight HA (LMW-HA) in terms of pain and functional improvement among knee osteoarthritis (OA) patients.

Methods

In this single-blinded RCT, the patients were randomly divided into two groups for HA injections. The first group received an HMW-HA (Arthromac) injection, while the other received three weekly LMW-HA (Hyalgan) injections. Pain and function were assessed using the outcome measures including WOMAC, Lequesne and VAS indices, once prior to injection, as well as 2 and 6 months after injections.

Results

A total of 90 patients were included. There was no significant difference in baseline characteristics including age and sex between the two groups. Our analysis showed that total WOMAC, Lequesne and VAS mean scores remarkably improved at both follow-up time-points compared to the baseline measurements (p < 0.001). There was no significant superiority between the two therapeutic protocols according to our outcome measures at any time-point of follow-up. The only except was about the improvement in WOMAC stiffness subscale that was significantly higher in LMW-HA group compared to HMW-HA (p = 0.021). Moreover, no significant difference was observed in minor complications and injection-induced pain scores between the two groups.

Conclusion

This study proved that a single HMW-HA injection is as effective as multiple injections of LMW-HA counterparts in periods of 2 and 6 months follow-up.

This study protocol was registered in Iranian database of RCTs (IRCT; www.irct.ir) with the trial registration number IRCT20130523013442N24 and registration date 2018-07-13.

Knee OA cost comparison for hyaluronic acid and knee arthroplasty

BACKGROUND

Limiting treatment to those recommended by the American Academy of Orthopaedic Surgeon Clinical Practice Guidelines has been suggested to decrease costs by 45% in the year prior to total knee arthroplasty, but this only focuses on expenditures leading up to, but not including, the surgery and not the entire episode of care. We evaluated the treatment costs following knee osteoarthritis (OA) diagnosis and determined whether these are different for patients who use intra-articular hyaluronic acid (HA) and/or knee arthroplasty.

METHODS

Claims data from a large commercial database containing de-identified data of more than 100 million patients with continuous coverage from 2012 to 2016 was used to evaluate the cumulative cost of care for over 2 million de-identified members with knee OA over a 4.5-year period between 2011 and 2015. Median cumulative costs were then stratified for patients with or without HA and/or knee arthroplasty.

RESULTS

Knee OA treatment costs for 1,567,024 patients over the 4.5-year period was $6.60 billion (mean $4210/patient) as calculated by the authors. HA and knee arthroplasty accounted for 3.0 and 61.5% of the overall costs, respectively. For patients who underwent knee arthroplasty, a spike in median costs occurred sooner for patients without HA use (around the 5- to 6-month time point) compared to patients treated with HA (around the 16- to 17-month time point).

CONCLUSIONS

Non-arthroplasty therapies, as calculated by the authors, accounted for about one third of the costs in treating knee OA in our cohort. Although some have theorized that limiting the use of HA may reduce the costs of OA treatment, HA only comprised a small fraction (3%) of the overall costs. Among patients who underwent knee arthroplasty, those treated with HA experienced elevated costs from the surgery later than those without HA, which reflects their longer time to undergoing knee arthroplasty. The ability to delay or avoid knee arthroplasty altogether can have a substantial impact on the cost to the healthcare system.

Development and Prospect of Intra-Articular Injection in the Treatment of Osteoarthritis: A Review

Osteoarthritis (OA) is a common degenerative disease that affects the vast majority of the elderly and may eventually embark on the road of the total knee arthroplasty (TKA), although controversy still exists in the medical community about the best therapies for osteoarthritis. Compared with physical therapy, oral analgesics and other non-operative treatments, intra-articular injection is more safe and effective. Moreover, intra-articular injection is much less invasive and has fewer adverse reactions than surgical treatment. This article reviews mechanism, benefits and adverse reactions of corticosteroids (CS), hyaluronic acid (HA), platelet-rich plasma (PRP), mesenchymal stem cell (MSCs), stromal vascular fraction (SVF) and other new therapies (for example: gene therapy). The application prospect of intra-articular injection was analyzed according to the recent progress in drug research.

Addition of High Molecular Weight Hyaluronic Acid to Fibroblast-Like Stromal Cells Modulates Endogenous Hyaluronic Acid Metabolism and Enhances Proteolytic Processing and Secretion of Versican

We have examined the effect of exogenous linear chain high molecular weight hyaluronic acid (HMW HA) on endogenously synthesized hyaluronic acid (HA) and associated binding proteins in primary cultures of fibroblast-like stromal cells that were obtained by collagenase digestion of the murine peripatellar fat pad. The cultures were expanded in DMEM that was supplemented with fetal bovine serum and basic fibroblast growth factor (bFGF) then exposed to macrophage-colony-stimulating factor (MCSF) to induce macrophage properties, before activation of inflammatory pathways using E. coli lipopolysaccharide (LPS). Under all culture conditions, a significant amount of endogenously synthesized HA localized in LAMP1-positive lysosomal vesicles. However, this intracellular pool was depleted after the addition of exogenous HMW HA and was accompanied by enhanced proteolytic processing and secretion of de novo synthesized versican, much of which was associated with endosomal compartments. No changes were detected in synthesis, secretion, or proteolytic processing of aggrecan or lubricin (PRG4). The addition of HMW HA also modulated a range of LPS-affected genes in the TLR signaling and phagocytosis pathways, as well as endogenous HA metabolism genes, such as Has1, Hyal1, Hyal2, and Tmem2. However, there was no evidence for association of endogenous or exogenous HMW HA with cell surface CD44, TLR2 or TLR4 protein, suggesting that its physiochemical effects on pericelluar pH and/or ionic strength might be the primary modulators of signal transduction and vesicular trafficking by this cell type. We discuss the implications of these findings in terms of a potential in vivo effect of therapeutically applied HMW HA on the modification of osteoarthritis-related joint pathologies, such as pro-inflammatory and degradative responses of multipotent mesenchymal cells residing in the synovial membrane, the underlying adipose tissue, and the articular cartilage surface.

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

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

Modeling and Staging of Osteoarthritis Progression Using Serial CT Imaging and Arthroscopy

OBJECTIVE

The objective of this study was to describe in life methods by which osteoarthritis can be staged in order to time therapeutic interventions that are relevant to osteoarthritis (OA) clinical trials.

METHODS

Twenty-two sheep underwent arthroscopic meniscal destabilization to induce OA. Serial computed tomography (CT) imaging and arthroscopy were used to monitor osteoarthritis progression at 3-month intervals over 9 months. Eleven sheep received 1 intra-articular injection of hyaluronate 3 months after OA induction and another group of 11 received saline. A linear mixed model was used to define the trajectory of shape change in the medial joint compartment. Ordinal logistic regression was used to investigate the association between morphological changes and sclerosis.

RESULTS

Three months after meniscal destabilization there were early bipolar chondral lesions in the medial compartment of the knee, as well as osteophytes and bone remodeling. Superficial fissures and cartilage cracks progressed to discrete areas of cartilage thinning and fibrillation on the medial tibial plateau by 6 months that became cartilage erosions by nine months. A linear mixed effect model demonstrated significant change in medial compartment length and width with over time (P < 0.05) for both groups. A significant association between severity of sclerosis and medial compartment morphology was also observed.

CONCLUSIONS

The induction of osteoarthritic lesions with meniscal release model can be followed using noninvasive and minimally invasive procedures allowing for real-time decisions about redosing therapies, or other changes such as extending trial timelines without sacrificing animals to conduct assessments.

On the Dependence of Rheology of Hyaluronic Acid Solutions and Frictional Behavior of Articular Cartilage

Hyaluronic acid (HA) injections represent one of the most common methods for the treatment of osteoarthritis. However, the clinical results of this method are unambiguous mainly because the mechanism of action has not been clearly clarified yet. Viscosupplementation consists, inter alia, of the improvement of synovial fluid rheological properties by injected solution. The present paper deals with the effect of HA molecular weight on the rheological properties of its solutions and also on friction in the articular cartilage model. Viscosity and viscoelastic properties of HA solutions were analyzed with a rotational rheometer in a cone-plate and plate-plate configuration. In total, four HA solutions with molecular weights between 77 kDa and 2010 kDa were tested. The frictional measurements were realized on a commercial tribometer Bruker UMT TriboLab, while the coefficient of friction (CoF) dependency on time was measured. The contact couple consisted of the articular cartilage pin and the plate made from optical glass. The contact was fully flooded with tested HA solutions. Results showed a strong dependency between HA molecular weight and its rheological properties. However, no clear dependence between HA molecular weight and CoF was revealed from the frictional measurements. This study presents new insight into the dependence between rheological and frictional behavior of the articular cartilage, while such an extensive investigation has not been presented before.

Injection route affects intra-articular hyaluronic acid distribution and clinical outcome in viscosupplementation treatment for knee osteoarthritis: a combined cadaver study and randomized clinical trial

The coverage of hyaluronic acid (HA) on the impaired cartilage should be the precondition to exert its beneficial effect on knee osteoarthritis (KOA) according to the pharmacological mechanism. However, the intra-articular distribution of HA might be correlated with the route of drug delivery. Forty-two cadaver knees with radiographic evidence of osteoarthritis were given anteromedial (AM) or medial midpatellar (MMP) injection of HA (molecular weight 600-1500 kD) followed by gait stimulation. Although 2.5 ml HA delivered through both routes failed to cover the entire cartilage, HA covered 96.12% cartilage of patellofemoral joint (PFJ) and 71.44% of medial femorotibial joint (FTJ) through MMP route, whereas mainly distributed into FTJ and posterior condyles through AM route. HA in the MMP group distributed more in PFJ than that in the AM group (P < 0.001), but no significant difference presented in medial FTJ (P = 0.084). The clinical efficacy was also associated with the route of drug delivery. One hundred patients with unilateral mild-to-moderate KOA were recruited and randomly assigned to receive five weekly HA injections with AM route (n = 50) or MMP route (n = 50). Patients in the MMP group obtained better improvement in WOMAC index total score, pain score, stiffness score, and Lequesne index total score over the entire follow-up period, as compared to patients in the AM group (all P < 0.01). More patients in the MMP group claimed pain relief (71.7%, P = 0.024) and felt satisfying (63.1%, P = 0.007) than in the AM group at the end of follow-up. Therefore, intra-articular HA injection through MMP route is recommended in treating mild-to-moderate KOA. Graphical Abstract .

Minimally Invasive Therapies for Osteoarthritic Hip Pain: a Comprehensive Review

PURPOSE OF REVIEW

Osteoarthritis (OA) is a highly prevalent cause of chronic hip pain, affecting 27% of adults aged over 45 years and 42% of adults aged over 75 years. Though OA has traditionally been described as a disorder of "wear-and-tear," recent studies have expanded on this understanding to include a possible inflammatory etiology as well, damage to articular cartilage produces debris in the joint that is phagocytosed by synovial cells which leads to inflammation.

RECENT FINDINGS

Patients with OA of the hip frequently have decreased quality of life due to pain and limited mobility though additional comorbidities of diabetes, cardiovascular disease, poor sleep quality, and obesity have been correlated. Initial treatment with conservative medical management can provide effective symptomatic relief. Physical therapy and exercise are important components of a multimodal approach to osteoarthritic hip pain. Patients with persistent pain may benefit from minimally invasive therapeutic approaches prior to consideration of undergoing total hip arthroplasty. The objective of this review is to provide an update of current minimally invasive therapies for the treatment of pain stemming from hip osteoarthritis; these include intra-articular injection of medication, regenerative therapies, and radiofrequency ablation.

[The efficacy and safety of intra-articular application of a combination of sodium hyaluronate and chondroitin sulfate for osteoarthritis of the knee: a multicenter prospective study]

in 3 mL on patients with knee osteoarthritis (OA) in a multicenter prospective study.

MATERIALS AND METHODS

79 outpatients (predominantly females 81.0%) from 5 RF constituent territories with primary tibiofemoral KellgrenLawrence score grade II or III knee OA, 40 mm pain intensity during walking on visual analogue scale (VAS), requiring NSAIDs intake (for at least 30 days during 3 months prior to enrollment) were included into the study after signing the informed consent form. Mean age was 60.38.7 years, mean BMI 29.24.7 kg/m2, disease duration 6 (310) years. Grade II OA was documented in 68.4% of patients, Grade III in 31.6%. The study lasted for 6 months. Efficacy and safety evaluations were made based on VAS pain assessment, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [WOMAC pain (0500), WOMAC function (01700), WOMAC stiffness (0200)], VAS patients health status, EQ-5D-based assessment of patients quality of life, global physicians and patients efficacy assessment, and daily NSAIDs requirements.

RESULTS

Obtained results demonstrate statistically significant VAS pain reduction during walking already in 1 week after intra-articular injection of the combination [respectively, 62 (5572) and 41 (3251) mm, р0.0001]. Moreover, pain continued to subside during all 3 months of follow up [in 1 month 28 (2042), in 3 month 22 (1437) mm]. A significant pan reduction achieved at Mo 3 persisted until Mo 6 20 (1442) mm, without documented pain increase. Similar trends were observed with total WOMAC score [1125 (8991540) at baseline, and 552 (309837) mm by the end of the study, p0.0001], and all WOMAC sub-scores [268 (189312) baseline WOMAC pain, 91 (48171) mm by the end of the study p0.0001; stiffness 101 (59130) and 40 (2061) mm, p0.0001; function 802 (6471095) and 402 (191638) mm, p0.0001, respectively]. Median time to the onset of therapeutic effect was 7 (518) days. Statistically significant improvement of patients quality of life by EQ-5D and general health status was observed during all follow up period [respectively, 0.52 (-0.020.59) and 0.69 (0.590.80), р0.0001; 48 (3060) and 72 (6080) mm, р0.0001]. One injection of the drug resulted in dose reduction or discontinuation of NSAIDs therapy: at baseline 76 patients (96.2%) were taking NSAIDs, in one week 31 (39.2%) patients discontinued NSAIDs, in 1 month 72.2%, in 3 months 73.4%, and by the end of the study at Mo 6 54.4% were not taking NSAIDs. These data were consistent with physicians and patients global assessment of the efficacy of treatment, who stated significant improvement and improvement in the majority of cases, with only few no effect or worsening cases documented in analyzed population. Adverse events, such as worsening of pain and/or swelling of the joint, were documented in 8 patients (10.1%); they resolved spontaneously or following NSAIDs intake.

CONCLUSION

These results suggest that intra-articular injections of hyaluronic acid plus chondroitin sulfate in patients with knee OA are efficient and safe. A single injection of the drug resulted in statistically significant reduction of pain and stiffness, reduction in NSAIDs intake, as well as improvement in patients quality of life and function.

Viscosupplementation may preserve tibial cartilage and collagen in osteoarthritis: findings from a preclinical model of osteoarthritis

PURPOSE

Intraarticular (IA) hyaluronic acid (HA) injection is used to reduce pain and improve mobility in knee osteoarthritis (OA). Little is known about histopathological changes underlying HA efficacy. This study investigated dose-related effects of 1% sodium hyaluronate (BioHA) on knee joint histopathology and pain responses in a medial meniscal tear (MMT) rat model of OA.

METHODS

Following MMT surgery, rats were randomized into treatment groups: single IA injection of vehicle, BioHA, or an avian-derived hyaluronic acid (hylan G-F 20) on Day 7; or 3 weekly injections of vehicle or BioHA on Days 7, 14, and 21. On Day 35, joints were evaluated by microscopic histopathology for cartilage degeneration, collagen degeneration, synovitis, and cytokine expression (tumor necrosis factor α, transforming growth factor β).

RESULTS

Joint pathology for control animals was consistent with that expected for the MMT model. Rats treated with 3 injections of IA-BioHA had significantly reduced collagen degeneration (21%) relative to control animals. No significant change in collagen degeneration was observed for rats given a single injection of hylan G-F 20 or IA-BioHA compared to control animals. HA treatment did not affect cytokine expression.

CONCLUSIONS

IA-BioHA viscosupplementation in a rat MMT model of OA showed preservation of joint cartilage and collagen. This effect was most pronounced on tibial surfaces having less severe injury, suggesting that treatment should be initiated early in the disease process. A comparison of responses to IA-BioHA or hylan G-F 20 in the MMT rat OA model suggest IA-BioHA may be more effective in preserving joint connective tissue.

Studies on the Mechanisms of Anti-Inflammatory Activity of Heparin- and Hyaluronan-Containing Multilayer Coatings-Targeting NF-κB Signalling Pathway

The use of implants can be hampered by chronic inflammatory reactions, which may result in failure of the implanted device. To prevent such an outcome, the present study examines the anti-inflammatory properties of surface coatings made of either hyaluronic acid (HA) or heparin (Hep) in combination with chitosan (Chi) prepared as multilayers through the layer-by-layer (LbL) technique. The properties of glycosaminoglycan (GAG)-modified surfaces were characterized in terms of surface topography, thickness and wettability. Results showed a higher thickness and hydrophilicity after multilayer formation compared to poly (ethylene imine) control samples. Moreover, multilayers containing either HA or Hep dampened the inflammatory response visible by reduced adhesion, formation of multinucleated giant cells (MNGCs) and IL-1β release, which was studied using THP-1 derived macrophages. Furthermore, investigations regarding the mechanism of anti-inflammatory activity of GAG were focused on nuclear transcription factor-кB (NF-κB)-related signal transduction. Immunofluorescence staining of the p65 subunit of NF-κB and immunoblotting were performed that showed a significant decrease in NF-κB level in macrophages on GAG-based multilayers. Additionally, the association of FITC-labelled GAG was evaluated by confocal laser scanning microscopy and flow cytometry showing that macrophages were able to associate with and take up HA and Hep. Overall, the Hep-based multilayers demonstrated the most suppressive effect making this system most promising to control macrophage activation after implantation of medical devices. The results provide an insight on the anti-inflammatory effects of GAG not only based on their physicochemical properties, but also related to their mechanism of action toward NF-κB signal transduction.

Hylan G-F20 and galactomannan joint flares are associated to acute synovitis and release of inflammatory cytokines

BACKGROUND

Injection of Hylan G-F20 (HY) into joints may provoke local flares, which mechanisms may involve reaction to protein contaminants. We have previously developed a protein-free saline-soluble galactomannan derived from guar gum (GM) that displays both analgesia and chondroprotection in experimental osteoarthritis (OA). We now demonstrate that both GM and Hylan G-F20 (HY) promote mild synovitis with cytokine release after intra-articular injection.

METHODS

Mice received 100 μg/25 μL GM or HY or saline into the knees. Joint pain was evaluated using von Frey test; cell influx, interleukin (IL)-1, IL-6, and CXCL-1 (pg/mL) levels were assessed in joint lavage at 6 h. Synovia were excised for histopathology.

RESULTS

Neither GM nor HY after being given into mice knee joints induced pain albeit promoting mild cell influx into joint washings as well as mild synovitis at histology, with no damage to the underlying cartilage. HY but not GM promoted IL-1 release into mice joints. Both compounds induced IL-6 and CXCL-1 release.

CONCLUSION

Intra-articular injection of HY or GM promote acute transient synovitis whilst not provoking detectable significant joint damage. Local administration of these polysaccharides induces acute intra-articular release of inflammatory cytokines, which may account for joint flares following viscosupplementation.

The use of cellular matrix in symptomatic knee osteoarthritis

Knee osteoarthritis is a degenerative "wear and tear" disorder affecting mainly population over 50 years old. It can also present in younger people, especially after an injury or as a part of other diseases. While many therapeutic options exist for knee osteoarthritis, none of them has the potential to cure this condition. Cellular Matrix represents a combination of natural non-crosslinked hyaluronic acid (HA), thixotropic cell separation gel, and sodium citrate anticoagulant solution. A combination of Cellular Matrix with autologous platelet-rich plasma (A-PRP) is a novel therapeutic approach to the management of knee osteoarthritis. It is assumed that the active components HA and PRP have a synergistic effect contributing to a better therapeutic outcome in patients with knee osteoarthritis. Physiotherapy could provide an additional benefit. This is a retrospective pilot study assessing the potential benefit of Cellular Matrix and A-PRP combined with physiotherapy in the management of chronic knee osteoarthritis. Twenty-five patients were enrolled in the study and injected with three doses of Cellular Matrix combined with A-PRP with a time span of 2 weeks between each injection. All patients received standardized physiotherapy. The results showed that 68% of patients achieved more than 50% improvement in pain, stiffness, and function of the knee joints. There were no adverse reactions. This retrospective pilot study confirmed the positive effect of PRP and HA combination in the management of mild and moderate knee osteoarthritis. These preliminary results need to be verified in randomized control trials.

A technological overview of cooled radiofrequency ablation and its effectiveness in the management of chronic knee pain

Knee osteoarthritis (OA) is a painful and sometimes debilitating condition affecting an estimated 14 million people in the USA alone. Management of knee OA begins with conservative medical treatments and progresses to total knee arthroplasty. Managing pain until a patient is eligible for arthroplasty remains a key part of the treatment algorithm for knee OA. Cooled radiofrequency ablation has shown clinical effectiveness in managing knee OA pain, with a majority of patients experiencing upwards of 12 months of analgesic effect. Herein is presented an overview of the technology of cooled radiofrequency ablation and a summary of current clinical trials demonstrating the treatments effectiveness.

Steering the Clinical Translation of Delivery Systems for Drugs and Health Products

Besides the feasibility for industrial scale-up, accelerating the translation from bench to bedside of new technological strategies for controlled delivery and targeting of drugs and other actives relevant for health management, such as medical devices and nutraceuticals, would benefit from an even earlier evaluation in pre-clinical models and clinical settings. At the same time, translational medicine also performs in the opposite direction, incorporating clinical needs and observations into scientific hypotheses and innovative technological proposals. With these aims, the sessions proposed for the 2019 CRS Italy Chapter Workshop will introduce the experience of Italian and worldwide researchers on how to foster the actual work in controlled release and drug delivery towards a reliable pre-clinical and clinical assessment.

Sodium Hyaluronate Supplemented Culture Media as a New hMSC Chondrogenic Differentiation Media-Model for in vitro/ex vivo Screening of Potential Cartilage Repair Therapies

Surgical strategies to treat articular cartilage injury such as microfracture, expose human bone marrow stem cells (hMSCs) to synovial fluid and its components. High molecular weight hyaluronan (hMwt HA) is one of the most abundant bioactive macromolecules of healthy synovial fluid (hSF) and it plays an important role in the protection of opposing articular cartilage surfaces within the synovial joint. Although hMwt HA has been extensively used to attempt the engineering of the cartilage tissue, its effect as media supplement has not been established. Indeed, current media are often simple in their composition and doesn't recapitulate the rheological and biological features of hSF. In addition, critical in vivo molecules that can potentially change the chondrogenic behavior of hBMSCs to make the in vitro results more predictive of the real in vivo outcome, are lacking. In order to be one step closer to the in vivo physiology of hSF, a new culture media supplemented with physiological level of hMwt HA was developed and the effect of the hMwt HA on the chondrogenesis of hMSCs that would be present in a traumatic defect after marrow stimulation techniques, was investigated. hBMSC-seeded fibrin-polyurethane constructs were cultured in a serum free chondropermissive control medium (HA- TGFβ-). This medium was further supplemented with 10 ng/mL TGFβ1 (HA- TGFβ+) or 2 mg/ml hMwt HA 1.8 MDa (HA+ TGFβ-) or both (HA+ TGFβ+). Alternatively, 1 MDa HA was mixed with the fibrin at 0.2 mg/ml (HASc TGFβ+). The effect of hMwt HA on hMSC differentiation was investigated at the gene expression level by RT-qPCR and total DNA, sulfated glycosaminoglycans and Safranin O staining were evaluated. Addition of hMwt HA to the culture media, significantly increased the synthesis of sulfated glycosaminoglycans, especially in the early days of chondrogenesis, and reduced the upregulation of the hypertrophic cartilage marker collagen X. hMwt HA added inside the fibrin gel(HASc TGF+) led to the best matrix deposition. hMwt HA can be one key medium component in a more reliable in vitro/ex vivo system to reduce in vitro artifacts, enable more accurate pre-screening of potential cartilage repair therapies and reduce the need for animal studies.

Hyaluronic acid has chondroprotective and joint-preserving effects on LPS-induced synovitis in horses

The intra-articular use of hyaluronic acid (HA) for the treatment of synovitis and osteoarthritis is still controversial. As a consequence, corticosteroids remain the most frequently employed therapeutic agents, despite their potential systemic and local deleterious effects. This study examined the anti-inflammatory, antioxidant, and chondroprotective activities of low and high molecular weight hyaluronic acid (LMW-HA and HMW-HA) on lipopolysaccharide (LPS)-induced synovitis in horses compared to triamcinolone acetonide (TA). LPS was injected in the metacarpophalangeal joints, which were treated intra-articularly with either TA (as control) or LMW-HA or HMW-HA. Joint clinical evaluation and synovial fluid (SF) analysis were performed at 0, 8, 24, and 48 h. The white blood cell counts (WBC), prostaglandin E2 (PGE2), interleukin (IL)-1, IL-6, IL-10, tumor necrosis factor-α, chondroitin sulfate (CS) and HA concentrations, oxidative burst, and HA molecular weights were measured. TA reduced the lameness, swelling, and PGE2 release but increased the SF CS concentrations enormously at 24h and 48h, and decreased the SF HA modal molecular weight. These results indicate the breakdown of articular cartilage aggrecan and SF HA. In contrast, LMW-HA and HMW-HA were less effective in reducing the inflammation symptoms, but preserved the joints because only a modest increase in CS occurred at 24 h, decreasing at 48 h, and the SF HA was maintained. The HA-treatment also had anti-inflammatory actions, and LMW-HA was the most effective in reducing the release of cytokine. In summary, the HA treatment inhibited efficiently the digestion of cartilage proteoglycans and SF HA breakdown.

Umbilical cord-derived Wharton's jelly for regenerative medicine applications

BACKGROUND

The last decade has seen an explosion in the interest in using biologics for regenerative medicine applications, including umbilical cord-derived Wharton's Jelly. There is insufficient literature assessing the amount of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes in these products. The present study reports the development of a novel Wharton's jelly formulation and evaluates the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles including exosomes.

METHODS

Human umbilical cords were obtained from consenting caesarian section donors. The Wharton's jelly was then isolated from the procured umbilical cord and formulated into an injectable form. Randomly selected samples from different batches were analyzed for sterility testing and to quantify the presence of growth factors, cytokines, hyaluronic acid, and extracellular vesicles.

RESULTS

All samples passed the sterility test. Growth factors including IGFBP 1, 2, 3, 4, and 6, TGF-α, and PDGF-AA were detected. Several immunomodulatory cytokines, such as RANTES, IL-6R, and IL-16, were also detected. Pro-inflammatory cytokines MCSFR, MIP-1a; anti-inflammatory cytokines TNF-RI, TNF-RII, and IL-1RA; and homeostatic cytokines TIMP-1 and TIMP-2 were observed. Cytokines associated with wound healing, ICAM-1, G-CSF, GDF-15, and regenerative properties, GH, were also expressed. High concentrations of hyaluronic acid were observed. Particles in the extracellular vesicle size range were also detected and were enclosed by the membrane, indicative of true extracellular vesicles.

CONCLUSION

There are numerous growth factors, cytokines, hyaluronic acid, and extracellular vesicles present in the Wharton's jelly formulation analyzed. The amount of these factors in Wharton's jelly is higher compared with other biologics and may play a role in reducing inflammation and pain and augment healing of musculoskeletal injuries.

Minimally Invasive Treatment of Chronic Ankle Instability: a Comprehensive Review

PURPOSE OF REVIEW

Chronic ankle pain is a prevalent and significant cause of chronic pain. While the definition of chronic ankle pain is heterogeneous and poorly defined in the literature, systematic reviews and meta-analyses have estimated this condition to be a prevalent and debilitating source of chronic pain. The most identifiable and prominent cause of chronic ankle pain is chronic ankle instability (CAI), a condition defined by instability of the ankle-joint complex. It is a common consequence of lateral ankle sprains or ligamentous injuries and can be described as a failure of the lateral ankle joint complex after an acute, or recurring, ankle injury. The objective of this manuscript is to provide a comprehensive review of CAI diagnosis and our current understanding of minimally invasive treatment options.

RECENT FINDINGS

First-line treatment is conservative management, some of which includes neuromuscular rehabilitation, balance training, nonsteroidal anti-inflammatory drugs (NSAIDs), manual mobilization, ice therapy, and compression. While conservative management is effective, additional treatments for those who fail conservative management, or who seek alternative options also have been explored. Recent advances and modern techniques have expanded available treatment options, many of which are becoming less invasive, and have shown improving functionality, recovery, and patient satisfaction. Minimally invasive treatments highlighted in this review include: arthroscopic surgery, steroid injections, plasma-rich plasma injections, hyaluronic acid (HA) injections, medicinal signaling cell injections, radiofrequency therapies, and shockwave therapies. This review will discuss some of these current treatments for minimally invasive treatment of CAI, as well as suggest novel treatments for clinical trials and further investigation.