Clostridium histolyticum (AA4500) for the Treatment of Adhesive Capsulitis of the Shoulder: A Randomised Double-Blind, Placebo-Controlled Study for the Safety and Efficacy of Collagenase - Single Site Report

The statistical fragility of treatments for adhesive capsulitis: a systematic review of randomized controlled trials

BACKGROUND

Randomized controlled trials (RCTs) have assessed a range of treatments for shoulder adhesive capsulitis (AC), with conflicting results over the most clinically beneficial options. This study used the fragility index (FI), reverse fragility index (rFI), and fragility quotient (FQ) to evaluate statistical fragility of the outcomes reported in RCTs assessing the efficacy of shoulder AC treatments.

METHODS

PubMed and Embase were systematically searched for RCTs from January 1, 2004, to May 1, 2024 that assessed shoulder AC treatments. We quantified FI and rFI, which represent the amount of outcome event reversals necessary to change statistical significance for significant and nonsignificant findings, respectively. Subanalyses were performed for outcomes relating to clinical efficacy, patient satisfaction, pain, and adverse events. The FQ was determined by dividing the FI by the study sample size.

RESULTS

Of 468 articles screened, there were a total of 38 RCTs analyzed that yielded 67 outcomes of interest. Across the 67 outcomes, the median FI was 3 (interquartile range [IQR] 2-6) and the median FQ was 0.075 (IQR 0.034-0.100). The 17 statistically significant outcomes had a median FI of 2 (IQR 1-4) and a median FQ of 0.050 (IQR 0.018-0.091). The remaining 50 outcomes were statistically nonsignificant, with a median FI of 4 (IQR 2-6) and a median FQ of 0.079 (IQR 0.037-0.102). Notably, in 40.3% of all outcomes, loss-to-follow-up was greater or equal to the outcome's respective FI or rFI. The most fragile outcomes were related to patient satisfaction (FI 2) and adverse events (FI 2.5).

CONCLUSION

The outcomes of interest regarding treatments for AC from RCTs are statistically fragile, most notably significant outcomes and those pertaining to patient satisfaction. RCT results surrounding AC treatments remain inconclusive; thus, combining P values with both FI and FQ metrics may improve the interpretation of clinical findings regarding treatment modalities for AC. Future clinical RCTs may reduce outcome fragility by improving follow-up rates and increasing patient sample sizes.

Analysis of risk factors and construction of nomogram model for arthroscopic single-row rivet repair

BACKGROUND

The factors influencing the clinical outcome of arthroscopic rotator cuff repair are not fully understood.

PURPOSE

To explore the factors related to the postoperative outcome of arthroscopic single-row rivet rotator cuff repair in patients with rotator cuff injury and to construct the related nomogram risk prediction model.

METHODS

207 patients with rotator cuff injury who underwent arthroscopic single-row rivet rotator cuff repair were reviewed. The differences of preoperative and postoperative Visual Analogue Score (VAS) scores and University of California, Los Angeles (UCLA) scores were analyzed and compared. The postoperative UCLA score of 29 points was taken as the critical point, and the patients were divided into good recovery group and poor recovery group, and binary logstic regression analysis was performed. According to the results of multivariate logistic regression analysis, the correlation nomogram model was constructed, and the calibration chart was used, AUC, C-index. The accuracy, discrimination and clinical value of the prediction model were evaluated by decision curve analysis. Finally, internal validation is performed using self-random sampling.

RESULTS

The mean follow-up time was 29.92 ± 17.20 months. There were significant differences in VAS score and UCLA score between preoperative and final follow-up (p < 0.05); multivariate regression analysis showed: Combined frozen shoulder (OR = 3.890, 95% CI: 1.544 ∼ 9.800), massive rotator cuff tear (OR = 3.809, 95%CI: 1.218 ∼ 11.908), More rivets number (OR = 2.118, 95%CI: 1.386 ∼ 3.237), lower preoperative UCLA score (OR = 0.831, 95%CI: 0.704-0.981) were adverse factors for the postoperative effect of arthroscopic rotator cuff repair. Use these factors to build a nomogram. The nomogram showed good discriminant and predictive power, with AUC of 0.849 and C-index of 0.900 (95% CI: 0.845 ∼ 0.955), and the corrected C index was as high as 0.836 in internal validation. Decision curve analysis also showed that the nomogram could be used clinically when intervention was performed at a threshold of 2%∼91%.

CONCLUSION

Combined frozen shoulders, massive rotator cuff tears, and increased number of rivets during surgery were all factors associated with poor outcome after arthroscopic rotator cuff repair, while higher preoperative UCLA scores were factors associated with good outcome after arthroscopic rotator cuff repair. This study provides clinicians with a new and relatively accurate nomogram model.

Rat shoulder contracture models: Techniques, evaluation, pathophysiology, and applications in developing treatment interventions

Studies on the pathophysiology of shoulder contracture and development of interventions have greatly benefited from the use of animal models. This narrative review comprehensively analyzes research on established rat model of shoulder contracture and new treatment approaches. This review evaluated existing literature on the available techniques for inducing contracture models, assessed these models, conducted pathological analyses, and explored their application in developing new treatment interventions. Our review highlights the usefulness of different rat shoulder contracture models, including external immobilization, internal immobilization, and intra-articular injection models, each with varying levels of success. Pathological analyses have demonstrated similarities to the human condition. The effective models have been instrumental in developing new treatment interventions, including recombinant human relaxin-2, platelet-rich plasma, collagenase clostridium histolyticum, and peroxisome proliferator-activated receptor-γ agonists. Therefore, rat shoulder contracture models serve as valuable tools for researchers to establish an effective animal model foundation for investigating the etiology and potential treatment.

The Versatility of Collagen in Pharmacology: Targeting Collagen, Targeting with Collagen

Collagen, a versatile family of proteins with 28 members and 44 genes, is pivotal in maintaining tissue integrity and function. It plays a crucial role in physiological processes like wound healing, hemostasis, and pathological conditions such as fibrosis and cancer. Collagen is a target in these processes. Direct methods for collagen modulation include enzymatic breakdown and molecular binding approaches. For instance, Clostridium histolyticum collagenase is effective in treating localized fibrosis. Polypeptides like collagen-binding domains offer promising avenues for tumor-specific immunotherapy and drug delivery. Indirect targeting of collagen involves regulating cellular processes essential for its synthesis and maturation, such as translation regulation and microRNA activity. Enzymes involved in collagen modification, such as prolyl-hydroxylases or lysyl-oxidases, are also indirect therapeutic targets. From another perspective, collagen is also a natural source of drugs. Enzymatic degradation of collagen generates bioactive fragments known as matrikines and matricryptins, which exhibit diverse pharmacological activities. Overall, collagen-derived peptides present significant therapeutic potential beyond tissue repair, offering various strategies for treating fibrosis, cancer, and genetic disorders. Continued research into specific collagen targeting and the application of collagen and its derivatives may lead to the development of novel treatments for a range of pathological conditions.

Agomir-122-loaded nanoparticles coated with cell membrane of activated fibroblasts to treat frozen shoulder based on homologous targeting

As a common musculoskeletal disorder, frozen shoulder is characterized by thickened joint capsule and limited range of motion, affecting 2-5% of the general population and more than 20% of patients with diabetes mellitus. Pathologically, joint capsule fibrosis resulting from fibroblast activation is the key event. The activated fibroblasts are proliferative and contractive, producing excessive collagen. Albeit high prevalence, effective anti-fibrosis modalities, especially fibroblast-targeting therapies, are still lacking. In this study, microRNA-122 was first identified from sequencing data as a potential therapeutic agent to antagonize fibroblast activation. Then, Agomir-122, an analog of microRNA-122, was loaded into poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Agomir-122@NP), a carrier with excellent biocompatibility for the agent delivery. Moreover, relying on the homologous targeting effect, we coated Agomir-122@NP with the cell membrane derived from activated fibroblasts (Agomir-122@MNP), with an attempt to inhibit the proliferation, contraction, and collagen production of abnormally activated fibroblasts. After confirming the targeting effect of Agomir-122@MNP on activated fibroblasts in vitro, we proved that Agomir-122@MNP effectively curtailed fibroblasts activation, ameliorated joint capsule fibrosis, and restored range of motion in mouse models both prophylactically and therapeutically. Overall, an effective targeted delivery method was developed with promising translational value against frozen shoulder.

An injectable thermosensitive hyaluronic acid/pluronic F-127 hydrogel for deep penetration and combination therapy of frozen shoulder

Frozen shoulder (FS) is a common and progressive shoulder disorder that causes glenohumeral joint stiffness, characterized by inflammation and fibrosis. The treatment options are quite limited, and the therapeutic response is hindered by the fibrous membrane formed by excessive collagen and the rapid removal by synovial fluid. To address these challenges, we designed a hyaluronic acid/Pluronic F-127 (HP)-based injectable thermosensitive hydrogel as a drug carrier loaded with dexamethasone and collagenase (HPDC). We screened for an optimal HP hydrogel that can sustain drug release for approximately 10 days both in vitro and in vivo. In the meanwhile, we found that HP hydrogel could inhibit the proliferation and diminish the adhesion capacity of rat synovial cells induced by transforming growth factor-β1. Furthermore, using an established immobilization rat model of FS, intra-articular injection of HPDC significantly improved joint range of motion compared to medication alone. Relying on sustained drug release, the accumulated collagen fibers were degraded by collagenase to promote the deep delivery of dexamethasone. These findings showed a positive combined treatment effect of HPDC, providing a novel idea for the comprehensive treatment of FS.

Frozen shoulder. An overview of pathology and biology with hopes to novel drug therapies

Frozen shoulder (FS) is a common disorder characterized by spontaneous onset of shoulder pain accompanied by progressive loss of range-of-motions. The cause of FS is still unclear, and radical therapy has not been established. With the final aim of preventing or curing FS at an earlier stage, we reviewed the pathological and biological features of this disease. Many studies indicate that the main pathology of FS is inflammation initially and fibrosis later. There are inflammatory cytokines, immune cells, fibrotic growth factors, and type-III collagen in the synovium and the joint capsule. The immune cell landscape switches from the macrophages to T cells. Activated fibroblasts seem to regulate the inflammatory and fibrotic processes. The imbalance between matrix metalloproteinases and tissue inhibitors of metalloproteases might promote fibrosis. Additionally, advanced glycation end-products are noted in the FS synovium. Diabetes mellitus and hypothyroidism are closely related to the development of FS. In terms of nonsurgical treatment, oral or intra-articular glucocorticoids are the only drugs that provide early benefit. Some other anti-inflammatory or antifibrotic drugs may potentially control the FS, but have not been proven effective in the clinical setting. Future studies should be targeted to develop steroid-sparing agents that inhibit biological events in FS.

Adhesive Capsulitis

Adhesive capsulitis, colloquially known as "frozen shoulder," is a relatively common disorder, affecting approximately 2% to 5% of the general population. The incidence may be higher as the condition can be relatively mild and self-limited and thus many patients who experience it may never present for treatment. It involves a pathologic process of gradual fibrosis of the glenohumeral joint that leads to limited active and passive range of motion, contracture of the joint capsule, and shoulder pain.

Human bone marrow mesenchymal stem cell-derived extracellular vesicles inhibit shoulder stiffness via let-7a/Tgfbr1 axis

Shoulder stiffness (SS) is a common shoulder disease characterized by increasing pain and limited range of motion. SS is considered to be an inflammatory and fibrotic disorder pathologically. However, there is no consensus on the most effective conservative treatment for fibrosis. Given that human Bone Marrow Mesenchymal Stem Cell-derived extracellular vesicles (BMSC-EVs) displayed promising therapeutic effects for various tissues, we investigated the therapeutic effect of BMSC-EVs on fibrosis in a mice immobilization model and two cell models. By conducting a series of experiments, we found that BMSC-EVs can significantly inhibit the fibrogenic process both in vitro and in vivo. In detail, BMSC-EVs suppressed the aberrant proliferation, high collagen production capacity, and activation of fibrotic pathways in TGF-β-stimulated fibroblasts in vitro. Besides, in vivo, BMSC-EVs reduced cell infiltration, reduced fibrotic tissue in the shoulder capsule, and improved shoulder mobility. In addition, via exosomal small RNA sequencing and qPCR analysis, let-7a-5p was verified to be the highest expressed miRNA with predicted antifibrotic capability in BMSC-EVs. The antifibrotic capacity of BMSC-EVs was significantly impaired after the knockdown of let-7a-5p. Moreover, we discovered that the mRNA of TGFBR1 (the membrane receptor of transforming growth factor β) was the target of let-7a-5p. Together, these findings elucidated the antifibrotic role of BMSC-EVs in shoulder capsular fibrosis. This study clarifies a new approach using stem cell-derived EVs therapy as an alternative to cell therapy, which may clinically benefit patients with SS in the future.

Frozen shoulder

Frozen shoulder is a common debilitating disorder characterized by shoulder pain and progressive loss of shoulder movement. Frozen shoulder is frequently associated with other systemic conditions or occurs following periods of immobilization, and has a protracted clinical course, which can be frustrating for patients as well as health-care professionals. Frozen shoulder is characterized by fibroproliferative tissue fibrosis, whereby fibroblasts, producing predominantly type I and type III collagen, transform into myofibroblasts (a smooth muscle phenotype), which is accompanied by inflammation, neoangiogenesis and neoinnervation, resulting in shoulder capsular fibrotic contractures and the associated clinical stiffness. Diagnosis is heavily based on physical examination and can be difficult depending on the stage of disease or if concomitant shoulder pathology is present. Management consists of physiotherapy, therapeutic modalities such as steroid injections, anti-inflammatory medications, hydrodilation and surgical interventions; however, their effectiveness remains unclear. Facilitating translational science should aid in development of novel therapies to improve outcomes among individuals with this debilitating condition.