Alleviation of peripheral sensitization by quadriceps insertion of cog polydioxanone filaments in knee osteoarthritis rats

Bidirectional barbed polydioxanone filament insertion in vastus medialis oblique muscle for knee osteoarthritis improvement

BACKGROUND

Strengthening the quadriceps muscle in patients with knee osteoarthritis (OA) can effectively alleviate symptoms such as pain and swelling. However, the use of bidirectional barbed polydioxanone filament (BBPF) for this purpose remains underexplored. Therefore, this study aimed to evaluate the impact of a new muscle enhancement and support therapy (MEST) involving the insertion of a BBPF into the vastus medialis obliquus (VMO) to improve the symptoms of knee OA.

METHODS

In a multicenter, randomized, double-blind study, we evaluated 131 patients over 40 with Kellgren-Lawrence grade II-III medial compartment knee OA. Of these, 88 received BBPF insertion into the VMO (MEST group), and 43 were in the control group. We compared pain levels (via a visual analog scale (VAS) during weight-bearing and walking), quadriceps muscle strength (IMCSQ), Patient Global Impression of Change (PGIC), and Clinical Global Impression of Change (CGIC), assessing outcomes before and after the procedure.

RESULTS

At four and eight weeks post-procedure, the VAS scores during weight-bearing and walking were significantly lower in the MEST group compared to the control group (P = 0.001). The differences in the IMCSQ at four and eight weeks post-procedure were significantly higher in the MEST group (P = 0.001). The PGIC and CGIC scores improved significantly at four weeks post-procedure (P = 0.001).

CONCLUSION

By reducing pain, improving function, and increasing muscle strength, MEST shows promise as a valuable addition to current treatment options. The biodegradable nature of the sutures suggests that repeat procedures may be beneficial, warranting further investigation to optimize this technique for wider clinical use.

The Efficacy of Polydioxanone Sutures in Treating Mild-to-Moderate Knee Osteoarthritis: A Systematic Review and Meta-Analysis

Background and Objectives: This meta-analysis aimed to compare the efficacy of polydioxanone (PDO) suture, a non-surgical treatment for knee osteoarthritis, with intra-articular hyaluronic acid (HA) injections. Materials and Methods: A comprehensive literature search was conducted using major databases including MEDLINE, EMBASE, Cochrane Library, KoreaMed, KMBASE, and RISS. Randomized controlled trials (RCTs) published up to 30 April 2024, focusing on knee osteoarthritis, pain, PDO suture, and intra-articular injections, were included. A total of 10 RCTs were analyzed, with participants having Kellgren & Lawrence Grade II-III knee osteoarthritis. This study compared the pain relief effects of PDO suture and HA injections. Results: The meta-analysis results showed that PDO suture demonstrated consistent and significant pain reduction over a 30-week observation period (p < 0.05), while HA injections did not exhibit statistically significant pain relief. Conclusions: PDO sutures offer the potential for long-term pain management in patients with knee osteoarthritis. However, this study has limitations such as the heterogeneity among studies, and given that the efficacy of PDO sutures is based on a single study, further research is needed to establish the long-term safety profile of polydioxanone sutures and to ensure the generalizability of the findings.

Evaluating the efficacy of intra-articular polydioxanone (PDO) injections as a novel viscosupplement in osteoarthritis treatment

AIMS

Osteoarthritis (OA) is a chronic joint disorder marked by cartilage breakdown, bone alterations, and inflammation, leading to significant pain and disability. Current therapeutic strategies, ranging from lifestyle interventions to pharmacological and surgical treatments, offer limited efficacy and are often accompanied by side effects. This study investigates the potential of Polydioxanone (PDO), a biocompatible synthetic polymer, as a novel intra-articular (IA) viscosupplement in OA.

MATERIALS AND METHODS

A validated rabbit model of OA was employed to compare the therapeutic effects of IA injections of PDO against established viscosupplements like hyaluronic acid (HA) and Conjuran (CJR). Sixty rabbits with collagenase-induced OA were randomized into four groups, receiving respective treatments over 12 weeks. The effect of PDO was analyzed by histopathological examination, immunofluorescence staining (IF), immunoblotting, quantitative real-time polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA).

KEY FINDINGS

The histopathological examination revealed substantial improvements in the PDO group's cartilage structure and matrix composition. qRT-PCR, IF staining, and Western Blot showed significant downregulation of matrix metalloproteinases (MMPs) and upregulation of type II collagen (COL II) and aggrecan (ACAN). ELISA results corroborated decreased inflammatory mediators- interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) in the PDO-treatment group.

SIGNIFICANCE

Preliminary results indicate that PDO may enhance cartilage regeneration and reduce inflammation, suggesting it is a viable and superior treatment option for OA. These findings merit further investigation to translate into clinical applications.

Ion channels in osteoarthritis: emerging roles and potential targets

Osteoarthritis (OA) is a highly prevalent joint disease that causes substantial disability, yet effective approaches to disease prevention or to the delay of OA progression are lacking. Emerging evidence has pinpointed ion channels as pivotal mediators in OA pathogenesis and as promising targets for disease-modifying treatments. Preclinical studies have assessed the potential of a variety of ion channel modulators to modify disease pathways involved in cartilage degeneration, synovial inflammation, bone hyperplasia and pain, and to provide symptomatic relief in models of OA. Some of these modulators are currently being evaluated in clinical trials. This review explores the structures and functions of ion channels, including transient receptor potential channels, Piezo channels, voltage-gated sodium channels, voltage-dependent calcium channels, potassium channels, acid-sensing ion channels, chloride channels and the ATP-dependent P2XR channels in the osteoarthritic joint. The discussion spans channel-targeting drug discovery and potential clinical applications, emphasizing opportunities for further research, and underscoring the growing clinical impact of ion channel biology in OA.

Quadriceps recovery and pain relief in knee osteoarthritis rats by cog polydioxanone filament insertion

Quadriceps muscles play a pivotal role in knee osteoarthritis (OA) progression and symptom manifestation, particularly pain. This research investigates the therapeutic effectiveness of muscle enhancement and support therapy (MEST), a recently developed device intended for intramuscular insertion of cog polydioxanone filaments, in quadriceps restoration to alleviate OA pain. Knee OA was induced in Sprague Dawley rats via monoiodoacetate injections. MEST or sham treatment was performed in OA or Naive rat quadriceps. Pain was assessed using paw withdrawal threshold and weight bearing. Quadriceps injury and recovery via MEST were evaluated using biomarkers, tissue morphology, muscle mass, contractile force and hindlimb torque. Satellite cell and macrophage activation, along with their activators, were also assessed. Data were compared at 1- and 3-weeks post-MEST treatment (M-W1 and M-W3). MEST treatment in OA rats caused muscle injury, indicated by elevated serum aspartate transferase and creatinine kinase levels, and local β-actin changes at M-W1. This injury triggered pro-inflammatory macrophage and satellite cell activation, accompanied by heightened interleukin-6 and insulin-like growth factor-1 levels. However, by M-W3, these processes gradually shifted toward inflammation resolution and muscle restoration. This was seen in anti-inflammatory macrophage phenotypes, sustained satellite cell activation and injury markers regressing to baseline. Quadriceps recovery in mass and strength from atrophy correlated with substantial OA pain reduction at M-W3. This study suggests that MEST-induced minor muscle injury triggers macrophage and satellite cell activation, leading to recovery of atrophied quadriceps and pain relief in OA rats.