Frozen shoulder

A mussel-inspired, antibacterial, antioxidant, injectable composite hydrogel for the sustain delivery of salvianolic acid B for the treatment of frozen shoulder

Frozen shoulder (FS) manifests as progressively worsening pain and a reduction in shoulder range of motion (ROM). Salvianolic acid B (SaB) is recently expected to be used in the treatment of fibrosis diseases including FS. We firstly demonstrate that SaB can effectively hinder the progression of oxidative stress, inflammation, and pathological fibrosis within the synovial tissue in FS, potentially leading to the reduction or reversal of capsule fibrosis and joint stiffness. For further clinical application, we design and synthesize a novel, superior, antioxidant and antibacterial CSMA-PBA/OD-DA (CPDA) hydrogel for the delivery of SaB. In vitro experiments demonstrate that the CPDA hydrogel exhibits excellent biocompatibility and rheological properties, rendering it suitable for intra-articular injections. Upon injection into the contracted joint cavity of FS model rat, the SaB-CPDA hydrogel accelerate the recovery of ROM and exhibit superior anti-fibrosis effect, presenting the promise for the treatment of FS in vivo.

Bioinformatics analysis of ferroptosis in frozen shoulder

OBJECTIVES

Frozen shoulder is a common shoulder disease that significantly affects the patient's life and work. Ferroptosis is a new type of programmed cell death, which is involved in many diseases. However, there have been no studies reporting the relationship between frozen shoulders and ferroptosis. This study identified potential molecular markers of ferroptosis in frozen shoulders to provide more effective strategies for the treatment of frozen shoulders.

METHODS

GSE238053 was downloaded from the Gene Expression Omnibus (GEO) dataset and intersected with ferroptosis genes to obtain differentially expressed genes (DEGs). The signaling pathways and biological functions of DEGs were performed by WebGestalt and Metascape. The interactions related to these DEGs and the key genes between frozen shoulders and ferroptosis was performed by STRING and Cytoscape. A frozen shoulders rat model was used to validate our predicted genes, Western Blot and qRT-PCR was used to assess the expression levels of our genes of interest.

RESULTS

A total of 34 DEGs between GSE238053 and Ferroptosis Database were obtained, most of which were involved in the HIF-1 signaling pathway and inflammatory response. A protein-protein interaction network was obtained by Cytoscape and the key genes (IL-6, HMOX1 and TLR4) were screened by MCODE. Our results of Western Blot showed that the protein expression level of TLR4 and HMOX1 were elevated, and the protein level of IL-6 decreased in frozen shoulders rat model. The mRNA level after frozen shoulders showed that IL-6 was upregulated, whereas TLR4 and HMOX1were downregulated.

CONCLUSIONS

The results demonstrated that ferroptosis may affect the pathological process of frozen shoulders through these signaling pathways and genes. The identification of IL-6, HMOX1 and TLR4 genes can provide new therapeutic targets for frozen shoulders.

Frozen shoulder: subjects' needs and perspectives and clinicians' beliefs and management strategies: do they align? A cross-sectional study

OBJECTIVE

Physiotherapists (PTs) play a crucial role in managing individuals with Frozen Shoulder (FS), frequently being the first healthcare professionals involved in the treatment of this condition.

AIM

This study aimed to compare the beliefs, expectations, and perspectives of individuals with FS with the knowledge, skills, and strategies of PTs, highlighting similarities and differences.

METHOD

This study adhered to the Checklist for Reporting Results of Internet E-Surveys (CHERRIES). From May 1st to August 1st, 2023, a two-part survey was conducted involving PTs and individuals diagnosed with FS. The survey focused on comparing key areas such as clinical assessment, patient education, treatment expectations, and the psychological aspects of the patient-clinician relationship.

RESULTS

A total of 501 PTs and 110 subjects with FS participated in the survey. Most PTs showed proficiency in FS pathoanatomical conditions and were also attentive to psychological aspects (88.4%), describing the pathology evolution in three or two stages (68.2%). They also highlighted the importance of patient education (89.6%) and recognized the potential benefits of a multiprofessional collaboration in managing FS (82.2%). Reassurance was reported as a priority by 32.3% of PTs. Subjects with FS expressed a preference for PTs who are both expert and empathetic (73.6%). Regarding their understanding of FS, 29.09% of subjects reported receiving a three-phase explanation, while 26.36% felt inadequately informed. Nearly half of the subjects (49.09%) anticipated being managed independently by a PT, with 93.64% prioritizing the improvement of their range of motion.

CONCLUSION

This study revealed a general agreement between subjects with FS and PTs regarding aspects of the therapeutic relationship, patient education, pathology management, compliance and motivation strategies, and pain management preferences. However, significant differences emerged concerning the perception of physiotherapy effectiveness, primary treatment goals, subjects' priorities, and the importance of psychological assessment.

Arthroscopic Arthrolysis for Recalcitrant Frozen Shoulder: Double Posterior Approach

Arthroscopic capsular release is required in some patients with frozen shoulder (FS). In some cases of recalcitrant FS, arthroscopic capsular release is difficult because of the abnormal narrowing of the joint space. The aim of this article is to introduce an arthroscopic double posterior approach combined with lateral and anterior approaches that is used to complete release of the glenohumeral joint capsule at 360°, subacromial debridement, and long head of biceps tenotomy. This article shows that this double posterior technique is a safe and highly effective totally intra-arthroscopic release technique for recalcitrant FS.

Rehabilitation in subjects with frozen shoulder: a survey of current (2023) clinical practice of Italian physiotherapists

OBJECTIVE

Frozen Shoulder (FS) is a musculoskeletal pathology that leads to disability, functional decline, and a worsening in quality of life. Physiotherapists are the primary professionals involved in the treatment of FS, and it is essential to determine if their practice aligns with evidence-based suggestions.

AIM

The aim is to assess the knowledge, skills, and operational strategies of Italian physiotherapists regarding FS and compare them with the existing literature.

METHODS

A web-based, anonymous, and voluntary cross-sectional survey was developed and administered to Italian physiotherapists to evaluate their clinical practices.

RESULTS

A total of 501 physiotherapists (38.5% female), completed the survey. More than half were under 35 years old (67.8%), declared working in private practice settings or being self-employed (57.1%), and were primarily engaged with musculoskeletal patients (81.8%). For subjects with FS at their first access, 21.4% identified X-rays as the most useful imaging technique to recognize pathologies beyond rehabilitation competence. In terms of general management, the majority reported working with an orthopaedic or physiatrist (47.5%) or in a multidisciplinary team (33.5%). Regarding manual therapy techniques, 63.3% of physiotherapists preferred intense degree mobilization, posterior direction, and moderate pain at the end of the range of motion for low irritable/high stiffness FS; however, there is a lack of consensus for managing very irritable/low stiffness FS. The majority of physiotherapists (57.7%) concurred that stretching improves the balance between metalloproteinase and its inhibitors. Additionally, 48.3% of physiotherapists selected mobile phone videos and messages to improve patients' compliance with exercises at home and for motivational/educational purposes.

DISCUSSION AND CONCLUSION

The clinical practices of Italian physiotherapists in FS subjects sometimes deviate from evidence-based recommendations. While some discrepancies may be attributed to the existing uncertainties in the literature regarding knowledge and management strategies for FS patients, the authors recommend a stronger adherence to evidence-based practice.

Combined MediaPipe and YOLOv5 range of motion assessment system for spinal diseases and frozen shoulder

Spinal diseases and frozen shoulder are prevalent health problems in Asian populations. Early assessment and treatment are very important to prevent the disease from getting worse and reduce pain. In the field of computer vision, it is a challenging problem to assess the range of motion. In order to realize efficient, real-time and accurate assessment of the range of motion, an assessment system combining MediaPipe and YOLOv5 technologies was proposed in this study. On this basis, Convolutional Block Attention Module (CBAM) is introduced into the YOLOv5 target detection model, which can enhance the extraction of feature information, suppress background interference, and improve the generalization ability of the model. In order to meet the requirements of large-scale computing, a client/server (C/S) framework structure is adopted. The evaluation results can be obtained quickly after the client uploads the image data, providing a convenient and practical solution. In addition, a game of "Picking Bayberries" was developed as an auxiliary treatment method to provide patients with interesting rehabilitation training.

Risk factors and predictive models for frozen shoulder

This study aims to explore the risk factors associated with frozen shoulder (FS) and develop a predictive model for diagnosing FS, in order to facilitate early detection of the condition. A total of 103 patients diagnosed with FS and admitted to the Department of Joint Surgery at Suining Central Hospital between October 2021 and October 2023 were consecutively included in the study. Additionally, 309 individuals without shoulder joint diseases, matched for age and gender, who visited the department during the same time, were included as the control group.The complete recording of clinical data for all patients was followed by the utilization of statistical tests such as the Mann-Whitney U test, sample t test, and chi-square test to compare different groups. Additionally, multivariate binary logistic regression analysis was employed to identify risk factors associated with the occurrence of FS in patients, leading to the establishment of a prediction model and derivation of a simplified equation. The diagnostic effectiveness of individual indicators and prediction models was assessed through the use of receiver operating characteristic (ROC) curve analysis. In the sample of 103 individuals, 35 were identified as male and 68 as female, with an average age range of 40-70 years (mean age: 54.20 ± 6.82 years). The analysis conducted between different groups revealed that individuals with a low body mass index (BMI), in conjunction with other factors such as diabetes, cervical spondylosis, atherosclerosis, and hyperlipidemia, were more susceptible to developing FS. Logistic regression analysis further indicated that low BMI, diabetes, cervical spondylosis, and hyperlipidemia were significant risk factors for the occurrence of FS. These variables were subsequently incorporated into a predictive model, resulting in the creation of a simplified equation.The ROC curve demonstrated that the combined indicators in the predictive model exhibited superior diagnostic efficacy compared to single indicators, as evidenced by an area under the curve of 0.787, sensitivity of 62.1%, and specificity of 82.2%. Low BMI, diabetes, cervical spondylosis, and hyperlipidemia are significant risk factors associated with the occurrence of FS. Moreover, the utilization of a prediction model has demonstrated superior capability in forecasting the likelihood of FS compared to relying solely on individual indicators. This finding holds potential in offering valuable insights for the early diagnosis of FS.

Exploring the link between metformin use and adhesive capsulitis of the shoulder: a retrospective cohort study in Taiwan

The risk of adhesive capsulitis of shoulder in diabetic patients taking metformin has not been evaluated. We aimed for evaluating the relative risk of adhesive capsulitis of shoulder in diabetic patients taking metformin at the level of the whole country population. We conducted a retrospective cohort study using a national health insurance database in Taiwan from 2000 to2015. We used International Classification of Diseases, Ninth Revision, to categorise the medical condition for study group and comparison group. We used Cox proportional hazard regression analyses to determined adjusted hazard ratios (aHRs) of adhesive capsulitis of shoulder between study and comparison group after adjusting for sex, age, and comorbidities.Among 30,412 diabetic patients using metformin, 3020 patients were diagnosis with adhesive capsulitis of shoulder during follow up. Of the 121,648 patients without the use of metformin, 11,375 patients developed adhesive capsulitis of shoulder. Adhesive capsulitis of shoulder risk was elevated in patients taking metformin than in non-metformin group (adjusted hazard ratio [HR] 1.179, 95% confidence interval [95% CI] 1.022 to 1.268; p = 0.039). Risk of adhesive capsulitis of shoulder among the diabetic patients taking metformin was higher than those did not taking metformin.

Arthroscopic Capsular Release Versus Manipulation under Anesthesia for Refractory Frozen Shoulder: A Systematic Review with Meta-Analysis

OBJECTIVE

Frozen shoulder (FS) is a painful and debilitating condition affecting the shoulder joint. When patients fail to improve after conservative treatments, operative treatments including arthroscopic capsular release (ACR) and manipulation under anesthesia (MUA) are recommended. However, the comparison between these two interventions remains controversial. This study aimed to compare the efficacy and safety of ACR and MUA for refractory FS.

METHODS

A systematic review and meta-analysis was conducted following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. PubMed, EMBASE, Cochrane Library, and Web of Science were searched for eligible studies until December 10, 2023. Meta-analyses were conducted using Manager V.5.3.3. Pooled effect sizes were expressed as the weighted mean difference (WMD) or odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

A total of eight comparative studies with 768 patients were included. Compared with MUA, ACR had statistically better Δ VAS (WMD, -0.44; 95% CI, -0.71 to -0.18; I2 = 6%; p = 0.001) at over 12-month follow-up, which did not reach the minimal clinically important difference (MCID). Other outcomes regarding pain relief, function, and range of motion (ROM) improvements were not statistically different between the two groups at different follow-up timepoints. Compared with the MUA group, the ACR group had a significantly higher rate of severe complications (OR, 4.14; 95% CI, 1.01 to 16.94; I2 = 0%; p = 0.05), but comparable rates of mild complications and additional intervention.

CONCLUSIONS

In treating refractory FS, ACR demonstrated comparable pain relief, functional and ROM improvements, rates of mild complications and additional intervention but a higher risk of severe complications to MUA during short-term follow-up periods. Notably, ACR exhibited statistically superior improvement in the long-term pain relief compared to the MUA group, although it did not reach the MCID.

Efficacy of hydrodistension for frozen shoulder: A systematic review and meta-analysis

BACKGROUND

The aim of this study was to provide comprehensive and reliable evidence for the treatment of pain and motor function in patients with frozen shoulder (FS) with hydrodistension.

METHODS

The research including randomized controlled trials (RCTs) for FS that compared hydrodistension with routine treatments to controls was searched and screened in the PubMed, Library of congress, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data Knowledge Service Platform, China Science and Technology Journal Database. Constant-Murley score (CMS) for shoulder function and visual analog scale (VAS) for pain must be assessed. RevMan 5.3 software was used to evaluate the bias and quality of the included studies.

RESULTS

We found that analgesic effects (MD: -1.07; 95% CI: -1.94 to -0.20; P < .00001; I2 = 99%) and function (MD: 8.54; 95% CI: 3.35 to 13.71; P < .00001; I2 = 97%) were better in the groups where hydrodistension plus routine treatments were used to treat FS compared to other interventions.

CONCLUSION

The result suggests that hydrodistension is of great clinical significance in alleviating pain and improving function to patients with FS.

Targeting the Sweet Spot: A Systematic Review With Meta-Analysis of Anterior Versus Posterior Glenohumeral Joint Injections for Adhesive Capsulitis

OBJECTIVE

To compare clinical outcomes following steroid injections using the anterior and posterior approaches.

DESIGN

Systematic review with meta-analysis.

SETTING

Embase, Web of Science, and Cochrane Center Register of Controlled Trials were searched for randomized control trials (RCTs) and prospective comparative studies.

PATIENTS

Patients with adhesive capsulitis.

INTERVENTIONS

Glenohumeral steroid injections using either anterior or posterior approach.

MAIN OUTCOME MEASURES

Pain visual analog scale (VAS) and shoulder range of motion (ROM) at 12 weeks, accuracy, and adverse events. Standardized mean difference (SMD) for VAS and weighted mean difference (WMD) for ROMs.

RESULTS

We identified 6 RCTs and one prospective comparative study with a total of 468 patients. While there was no difference in pain VAS at 12 weeks between the 2 approaches (SMD, -0.86; 95% CI, -1.76 to 0.04), the anterior approach resulted in greater improvements in external rotation (WMD, 8.08; 95% CI, 0.79-15.38) and abduction (WMD, 6.76; 95% CI, 3.05-10.48) compared with the posterior approach. Subgroup analysis with RCTs that utilized steroid injection with hydrodilatation for both approaches demonstrated greater reduction in pain VAS at 12 weeks with the anterior approach (SMD, -0.52; 95% CI, -0.98 to -0.07). Overall, procedures were well tolerated without major complications.

CONCLUSIONS

While pain reduction is similar, the anterior approach may be more beneficial in restoring shoulder external rotation and abduction compared with the posterior approach at 12 weeks. Steroid injection combined with hydrodilatation may further improve pain control when performed with the anterior approach at 12 weeks.

The Feasibility and Efficacy of Remote App-Guided Home Exercises for Frozen Shoulder: A Pilot Study

Home exercise programs are beneficial in managing frozen shoulder (FS), yet adherence remains challenging. This pilot study introduces the remote app, Defrozen, designed for home exercises and assesses its feasibility and clinical outcomes in FS patients undergoing intra-articular and sub-acromial corticosteroid treatment. Over a four-week period, patients used the Defrozen-app, engaging in guided exercises. The feasibility of the intervention was assessed through several measurement scales, including adherence, the Technology Acceptance Model 2 (TAM2), the System Usability Scale (SUS), and User Satisfaction and Engagement (USE). Clinical outcomes included pain scale, Oxford Shoulder Score (OSS), Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) Score, and passive range of motion. The TAM2 results indicated high perceived usefulness (4.5/5), ease of use (4.8/5), and intention to use (4.4/5); the SUS score was high at 81.7/100, complemented by USE scores reflecting ease of learning (4.9/5) and satisfaction (4.3/5). Clinical outcomes showed significant pain reduction, improved shoulder function, reduced shoulder-related disability, and increased shoulder range of motion. These findings suggest the Defrozen-app as a promising solution for FS, significantly improving adherence and showing potential to enhance clinical outcomes. However, these clinical outcome results are preliminary and necessitate further validation through a large-scale randomized controlled trial to definitively confirm efficacy and assess long-term benefits.

Subacromial bursa in patients with rotator cuff tear with or without adhesive capsulitis exhibits a differential transcriptome with potential molecular biomarkers

Background

Although adhesive capsulitis (AC) is a common condition, the pathological mechanisms remain understudied. The purpose of our research was to evaluate variations in gene expression across the entire genome in the subacromial bursa tissue of individuals with rotator cuff tears (RCT), with or without AC, and to explore the factors that may influence the occurrence and progression of AC.

Methods

Transcription profiles of subacromial bursa samples from 12 RCT patients, of whom 6 had also AC, were evaluated. Data were generated using RNA-seq. DESeq2 was utilized to identify the differentially expressed genes (DEGs) in both groups. In order to conduct a more in-depth examination of the DEGs, we performed Gene Ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. A network of interactions between proteins was built, and the central genes were determined using Cytoscape. The hub genes were confirmed through qRT-PCR and immunohistochemistry.

Results

324 of the 16,251 detected genes were identified as DEGs. Analysis of GO functional enrichment showed that the DEGs were enriched in domains of biological process, molecule function and cellular component. Analysis of KEGG pathways revealed enrichment of DEGs in pathways like IL-17 signaling and ECM-receptor interaction. We verified that the association between AC and the increase in expression of the PPI network hub genes.

Conclusion

This study investigated the transcriptome differences of subacromial bursa in RCT patients with or without AC. Using bioinformatics technology, we identified the DEGs and screened out the hub genes. The research enhanced the data on gene expression profiles of DEGs in the subacromial bursa tissue of patients with RCT, offering fresh perspectives on the regulation of gene transcription.

Unveiling potential therapeutic targets for diabetes-induced frozen shoulder through Mendelian randomization analysis of the human plasma proteome

INTRODUCTION

This study aimed to assess the causal relationship between diabetes and frozen shoulder by investigating the target proteins associated with diabetes and frozen shoulder in the human plasma proteome through Mendelian randomization (MR) and to reveal the corresponding pathological mechanisms.

RESEARCH DESIGN AND METHODS

We employed the MR approach for the purposes of establishing: (1) the causal link between diabetes and frozen shoulder; (2) the plasma causal proteins associated with frozen shoulder; (3) the plasma target proteins associated with diabetes; and (4) the causal relationship between diabetes target proteins and frozen shoulder causal proteins. The MR results were validated and consolidated through colocalization analysis and protein-protein interaction network.

RESULTS

Our MR analysis demonstrated a significant causal relationship between diabetes and frozen shoulder. We found that the plasma levels of four proteins were correlated with frozen shoulder at the Bonferroni significance level (p<3.03E-5). According to colocalization analysis, parathyroid hormone-related protein (PTHLH) was moderately correlated with the genetic variance of frozen shoulder (posterior probability=0.68), while secreted frizzled-related protein 4 was highly correlated with the genetic variance of frozen shoulder (posterior probability=0.97). Additionally, nine plasma proteins were activated during diabetes-associated pathologies. Subsequent MR analysis of nine diabetic target proteins with four frozen shoulder causal proteins indicated that insulin receptor subunit alpha, interleukin-6 receptor subunit alpha, interleukin-1 receptor accessory protein, glutathione peroxidase 7, and PTHLH might contribute to the onset and progression of frozen shoulder induced by diabetes.

CONCLUSIONS

Our study identified a causal relationship between diabetes and frozen shoulder, highlighting the pathological pathways through which diabetes influences frozen shoulder.

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.

Psychometric properties of the Disability of Arm Shoulder and Hand (DASH) in subjects with frozen shoulder: a reliability and validity study

BACKGROUND

Frozen Shoulder (FS) is a painful condition characterized by severe pain and progressive restriction of shoulder movement, leading to functional impairment and reduced quality of life. While different Patient Reported Outcome Measurements (PROMs) tools exist for assessing shoulder diseases, few specific PROMs are validated for FS patients.

PURPOSE

This study aims to assess the psychometric properties of the Disability of Arm, Shoulder, and Hand (DASH) questionnaire in FS patients.

METHODS

One hundred and twenty-four subjects (mean ± SD age = 55.4 ± 7.9 years; 55.6% female) diagnosed with FS were included and completed the DASH questionnaire, the Numerical Pain Rating Scale (NPRS), the Shoulder Pain and Disability Index (SPADI), and the Short-Form Health Survey 36 (SF-36). Floor or ceiling effects were investigated. Structural validity was analysed through a unidimensional Confirmatory Factor Analysis (CFA), internal consistency through Cronbach's alpha, test-retest reliability through the Intraclass Correlation coefficient (ICC), measurement error through the Standard Error of Measurement (SEM), and the Minimum Detectable Change (MDC), and construct validity through the hypothesis testing with the correlation with the other outcome measures used.

RESULTS

No floor or ceiling effects were observed. CFA confirmed a one-factor structure after addressing local item dependency (Root Mean Square Error of Approximation = 0.055; Standardized Root Mean Square Residual = 0.077; Comparative Fit Index = 0.970; Tucker-Lewis Index = 0.968). Cronbach's alpha was high (= 0.951), and test-retest reliability was excellent (ICC = 0.999; 95% CI: 0.998-1.000). SEM was equal to 0.5 points, and MDC to 1.5 points. Construct validity was considered satisfactory as 80% of the a-priori hypotheses were met.

CONCLUSION

The DASH questionnaire demonstrated good psychometric properties in FS patients, supporting its use as a valuable tool for assessing the impact of FS in clinical and research settings.

Evaluating the Patterns of FAPI Uptake in the Shoulder Joint: a Preliminary Study Comparing with FDG Uptake in Oncological Studies

BACKGROUND

Fibroblast activation protein inhibitor (FAPI) targeting PET has been introduced as a novel molecular imaging modality for visualizing cancer-associated fibroblasts. There have also been reports suggesting incidental findings of localized accumulation in the shoulder joints. However, further characterization in a larger patient cohort is still lacking.

METHODS

77 consecutive patients (28 females; mean age, 63.1 ± 11.6) who underwent Ga-68 FAPI-04 PET/CT for diagnosis of solid tumors were included. The incidence and localization of tracer uptake in shoulder joints were investigated and compared with available F-18 FDG scans serving as reference.

RESULTS

Ga-68 FAPI-04 uptake was evaluated in 77 patients (154 shoulder joints), of whom 54 subjects (108 shoulder joints) also had available F-18 FDG scans for head-to-head comparison. On FAPI-targeted imaging, 67/154 shoulders (43.5%) demonstrated increased radiotracer accumulation in target lesions, which were distributed as follows: acromioclavicular (AC) joints in 25/67 (37.3%), followed by glenohumeral and subacromial (GH + SA) joints in 23/67 (34.3%), or both (AC and GH + SA joints) in the remaining 19/67 (28.4%). Ga-68 FAPI-04 correlated with quantified F-18 FDG uptake (r = 0.69, p < 0.0001). Relative to the latter radiotracer, however, in-vivo FAP expression in the shoulders was significantly increased (Ga-68 FAPI-04, 4.7 ± 3.2 vs F-18 FDG, 3.6 ± 1.3, p < 0.001).

CONCLUSION

Our study revealed focal accumulation of Ga-68 FAPI-04 in the shoulders, particularly in the AC joints, with higher uptake compared to the inflammatory-directed PET radiotracer F-18 FDG in oncological studies. As a result, further trials are warranted to investigate the potential of FAPI-directed molecular imaging in identifying chronic remodeling in shoulder joints. This could have implications for initiating anti-FAP targeted photodynamic therapy based on PET signal strength.

Structural and functional abnormalities in the medial prefrontal cortex were associated with pain and depressive symptoms in patients with adhesive capsulitis

Introduction

Chronic pain and depression have been shown to coexist in patients with adhesive capsulitis (AC). Recent studies identified the shared brain plasticity between pain and depression; however, how such neuroplasticity contributes to AC remains unclear. Here, we employed a combination of psychophysics, structural MRI, and functional MRI techniques to examine the brain's structural and functional changes in AC.

Methods

Fifty-two patients with AC and 52 healthy controls (HCs) were included in our study. Voxelwise comparisons were performed to reveal the differences in grey matter volume (GMV) and regional homogeneity (ReHo) between AC and HCs. Furthermore, region of interest to whole brain functional connectivity (FC) was calculated and compared between the groups. Finally, Pearson correlation coefficients were computed to reveal the association between clinical data and brain alterations. Mediation analyses were performed to investigate the path association among brain alterations and clinical measures.

Results

Three main findings were observed: (1) patients with AC exhibited a higher depression subscale of hospital anxiety and depression scale (HADS-D) score correlating with the GMV within the right medial prefrontal cortices (mPFC) compared with HCs; (2) relative to HCs, patients with AC exhibited lower ReHo within the right mPFC, which largely overlapped with the structural abnormalities; (3) the impact of pain duration on HADS-D score was mediated by ventral part of medial prefrontal cortices (vmPFC) GMV in patients with AC.

Conclusion

In summary, our current findings suggest that vmPFC alterations correlate with both the pain duration and the emotional comorbidities experienced by patients with AC. Our research provides an enhanced comprehension of the underlying mechanisms of AC, thereby facilitating the development of more effective treatment approaches for AC.

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.

A new perspective of frozen shoulder pathology; the interplay between the brain and the immune system

Frozen shoulder (FS), also known as adhesive capsulitis of the shoulder (FS), is a fibrotic inflammatory process of unknown etiology whose main symptoms are pain, stiffness and the loss of joint mobility. These symptoms may be associated with pathologies such as diabetes, Dupuytren's syndrome and the prevalence of today's sedentary lifestyle. This literature review provides an overview of the epidemiology and pathogenesis of this pathology, as well as the mechanisms of lowgrade chronic inflammation and infection, insulin resistance, and omics-science associated with it. We also propose a new hypothesis related to the possibility that the GABAergic system could play a decisive role in the development of frozen shoulder and that therefore diabetes type 1, endocrinological autoimmune disorders and frozen shoulder are connected by the same pathophysiological mechanisms. If that is true, the combined presence of psycho-emotional stress factors and pathogenic immune challenges could be the main causes of frozen shoulder syndrome. Finally, we propose a series of possible intervention strategies based on a multifactorial etiological and mechanistic concept.

Similar outcomes between arthroscopic capsular release and manipulation under anaesthesia for frozen shoulder: A meta-analysis

To compared the arthroscopic capsular release (ACR) with manipulation under anaesthesia (MUA) for the surgical treatment of frozen shoulder (FS) based on postoperative outcomes and complications. PubMed, Cochrane Library, Embase, and Web of Science were searched on October 2, 2023 to retrieve eligible studies that compared ACR with MUA in terms of clinical outcomes (pain visual analogue scale, external rotation, forward flexion and adverse events) for patients with FS. Mean differences (MD) were calculated for continuous outcomes and odds ratios (OR) were calculated for dichotomous outcomes. Six papers, including 5 clinical studies (a total of 690 shoulders), were included in the final meta-analysis. The forward flexion was found to be larger in the ACR group at 3 months (MD, 2.73; 95%CI, 0.42-5.04; I2 = 44%; P = 0.02) and 6 months (MD, 2.36; 95%CI, 1.29-3.44; I2 = 0%; P < 0.0001). Except for this, ACR was comparable with MUA in terms of pain visual analogue scale at 3, 6 and 12 months (p = 0.25, p = 0.11, p = 0.28, respectively), external rotation at 3, 6 and 12 months (p = 0.15, p = 0.52, p = 0.23, respectively), and forward flexion at 12 months (p = 0.08). There were no differences in complication rates between the two groups (OR, 0.82; 95%CI, 0.47-1.44; I2 = 0%; P = 0.50). In comparison with MUA, ACR demonstrated better outcomes for forward flexion at 3 and 6 months, while there were no significant differences between ACR and MUA in terms of pain visual analogue scale, external rotation and adverse events.

Impact of open bursectomy and biceps tendon release with closed manipulation in frozen shoulder

This retrospective observational study evaluated the efficacy of 2 different surgical approaches for the treatment of frozen shoulder (adhesive capsulitis). This study aimed to compare the efficacy, safety, and recovery times of the 2 treatment modalities. Fifty patients diagnosed with frozen shoulder and treated at Seyhan State Hospital were included in the study. The patients were retrospectively divided into 2 groups based on the treatment received. Group 1 consisted of 25 patients who underwent standard closed manipulation under anesthesia, a technique involving passive movements of the shoulder joint to tear the tight capsule and expand the range of motion (ROM). Group 2, which included 25 patients, underwent closed manipulation in addition to open bursectomy and biceps tendon capsule release. Open bursectomy involves surgical removal of the bursa to alleviate inflammation, while biceps tendon capsule release addresses chronic biceps tendonitis by partially removing the capsule of the tendon. Data on demographic information, operative details, preoperative and postoperative conditions, and patient-reported outcomes were collected and analyzed. Data analysis revealed that the combination of closed manipulation with open bursectomy and biceps tendon capsule release was more effective in reducing pain, increasing ROM, and improving quality of life than closed manipulation alone. The discussion would typically elaborate on how the results compare with existing literature, the clinical implications, and any potential limitations of the study. The results showed that the method that combined closed manipulation with open bursectomy and biceps tendon capsule release was better than closed manipulation alone in terms of reducing pain, increasing ROM, and improving quality of life.

Rotator cuff tears

Rotator cuff tears are the most common upper extremity condition seen by primary care and orthopaedic surgeons, with a spectrum ranging from tendinopathy to full-thickness tears with arthritic change. Some tears are traumatic, but most rotator cuff problems are degenerative. Not all tears are symptomatic and not all progress, and many patients in whom tears become more extensive do not experience symptom worsening. Hence, a standard algorithm for managing patients is challenging. The pathophysiology of rotator cuff tears is complex and encompasses an interplay between the tendon, bone and muscle. Rotator cuff tears begin as degenerative changes within the tendon, with matrix disorganization and inflammatory changes. Subsequently, tears progress to partial-thickness and then full-thickness tears. Muscle quality, as evidenced by the overall size of the muscle and intramuscular fatty infiltration, also influences symptoms, tear progression and the outcomes of surgery. Treatment depends primarily on symptoms, with non-operative management sufficient for most patients with rotator cuff problems. Modern arthroscopic repair techniques have improved recovery, but outcomes are still limited by a lack of understanding of how to improve tendon to bone healing in many patients.

Efficacy of combined ultrasound-guided hydrodilatation with hyaluronic acid and physical therapy in patients with adhesive capsulitis: A randomised controlled trial

OBJECTIVE

To evaluate the therapeutic effect of combining ultrasound-guided hydrodilatation with hyaluronic acid and physical therapy compared with physical therapy alone in patients with adhesive capsulitis.

DESIGN

A prospective, single-blinded, randomised controlled trial.

SETTING

Single medical centre.

PARTICIPANTS

Patients with adhesive capsulitis (N = 62) were divided into group A: ultrasound-guided hydrodilatation with hyaluronic acid + physical therapy (N = 31) and group B: physical therapy alone (N = 31).

INTERVENTIONS

Group A received three doses of ultrasound-guided hydrodilatation with hyaluronic acid-based injectates (20 mL in total). Both groups underwent structured physical therapy.

OUTCOME MEASURES

The primary outcome measure was Constant score, while secondary outcomes included Shoulder Pain and Disability Index score, numerical rating scale (at rest, night, and during motion), 36-item Short Form Health Survey, and range of motion of the shoulder. All measurements were collected at baseline, 6 weeks, and 12 weeks post-injection.

RESULTS

At week 12, the Constant scores were 68.29 ± 14.55 and 62.77 ± 14.44 for groups A and B, respectively. There was a greater reduction in the Constant score, Shoulder Pain and Disability Index, and numerical rating scale between the baseline and 6 weeks and between the baseline and 12 weeks in group A (Constant score: p < 0.05, Shoulder Pain and Disability Index: p < 0.01, and numerical rating scale: p < 0.05).

CONCLUSION

The combination of ultrasound-guided hydrodilatation with hyaluronic acid in conjunction with physical therapy provides additional benefits compared to physical therapy alone for the treatment of adhesive capsulitis at up to 12 weeks.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02708706.

Type 2 diabetes and fasting glycemic traits are causal factors of frozen shoulder: a 2-sample Mendelian randomization analysis

BACKGROUND

The causal relationship between type 2 diabetes (T2D) and frozen shoulder is unclear. This study aims to explore the genetic causal association between T2D and glycemic traits (fasting glucose [FG], fasting insulin [FI], glycated hemoglobin [HbA1c], and 2-hour postprandial glucose [2hGlu]) on frozen shoulder.

METHODS

Using 2-sample Mendelian randomization (MR), we analyzed nonconfounded estimates of the effects of T2D and glycemic traits on frozen shoulder. Single-nucleotide polymorphisms (SNPs) strongly associated (P < 5 × 10-8) with exposures from genome-wide association studies (GWAS) were identified. We employed fixed effect mode inverse variance weighting (IVW-FE), random effect mode IVW (IVW-MRE), MR-Egger, and weighted median to assess the association of exposures and outcome. Sensitivity analysis was conducted to test for heterogeneity and multidirectionality bias in MR.

RESULTS

We found a significant genetic causal correlation between T2D (IVW-MRE P = .007, odds ratio [OR] 1.093, 95% confidence interval [CI] 1.03-1.16), FG (IVW-FE P < .001, OR 1.455, 95% CI 1.173-1.806), and frozen shoulder, but no evidence for causal correlation between FI, HbA1c, and 2hGlu and frozen shoulder. Although there was certain heterogeneity, sensitivity analysis reveals no deviation from the MR assumptions.

CONCLUSION

This study supports a genetic causal relationship between T2D and FG and frozen shoulder.

Genetic causal association between frozen shoulder and carpal tunnel syndrome: a two-sample mendelian randomization

OBJECTIVE

Observational studies have suggested an association between frozen shoulder (FS) and carpal tunnel syndrome (CTS). However, due to challenges in establishing a temporal sequence, the causal relationship between these two conditions remains elusive. This study, based on aggregated data from large-scale population-wide genome-wide association studies (GWAS), investigates the genetic causality between FS and CTS.

METHODS

Initially, a series of quality control measures were employed to select single nucleotide polymorphisms (SNPs) closely associated with the exposure factors. Two-sample Mendelian randomization (MR) was utilized to examine the genetic causality between FS and CTS, employing methods including Inverse-Variance Weighted (IVW), MR-Egger, Weighted Median, Simple Mode, and Weighted Mode approaches. Subsequently, sensitivity analyses were conducted to assess the robustness of the MR analysis results.

RESULTS

IVW analysis results indicate a positive causal relationship between CTS and FS (p < 0.05, OR > 1), while a negative causal relationship between the two conditions was not observed. Heterogeneity tests suggest minimal heterogeneity in our IVW analysis results (p > 0.05). Multivariable MR testing also indicates no pleiotropy in our IVW analysis (p > 0.05), and stepwise exclusion tests demonstrate the reliability and stability of the MR analysis results. Gene Ontology (GO) pathway analysis reveals enrichment of genes regulated by the associated SNPs in the TGFβ-related pathways.

CONCLUSION

This study provides evidence of the genetic causal association between frozen shoulder and carpal tunnel syndrome and provides new insights into the genetics of fibrotic disorders.

Efficacy of Platelet-Rich Plasma Injection on Range of Motion, Pain, and Disability in Patients With Adhesive Capsulitis: A Systematic Review and Meta-analysis

OBJECTIVE

To investigate the therapeutic effects of platelet-rich plasma (PRP) injection on range of motion, pain, and disability in patients with adhesive capsulitis (AC).

DATA SOURCES

The authors performed the literature search in the PubMed, Embase, and Cochrane Library databases in February 2023.

STUDY SELECTION

Prospective studies comparing the outcomes of PRP with other intervention in patients with AC.

DATA EXTRACTION

The quality of included randomized trials was assessed using the revised Cochrane Risk of Bias (RoB 2.0) tool. The Risk of Bias in Non-Randomized Studies of Interventions tool was applied to assess the quality of nonrandomized trials. The mean difference (MD) or standardized mean difference (SMD) was determined as the effect size for continuous outcomes, and outcome accuracy was determined using 95% confidence intervals (CIs).

DATA SYNTHESIS

Fourteen studies involving 1139 patients were included. Our meta-analysis revealed that PRP injection can significantly improve passive abduction (MD=3.91; 95% CI, 0.84-6.98), passive flexion (MD=3.90; 95% CI, 0.15-7.84), and disability (SMD=-0.50; 95% CI, -1.29 to -0.74) within 1 month after intervention. Moreover, PRP injection can significantly improve passive abduction (MD=17.19; 95% CI, 12.38-22.01), passive flexion (MD=17.74; 95% CI, 9.89-25.59), passive external rotation (MD=12.95; 95% CI, 10.04-15.87), pain (MD=-8.40; 95% CI, -16.73 to -0.06), and disability (SMD=-1.02; 95% CI, -1.29 to -0.74) 3 months after intervention. PRP injection can also significantly improve pain (MD=-18.98; 95% CI, -24.71 to -13.26), and disability (SMD=-2.01; 95% CI, -3.02 to -1.00) 6 months after intervention. In addition, no adverse effects of PRP injection were reported.

CONCLUSIONS

PRP injection may serve as an effective and safe treatment for patients with AC.

The diagnostic value of physical examination tests in adhesive capsulitis: a systematic review

INTRODUCTION

Adhesive capsulitis, a condition marked by pain and stiffness of the shoulder, can have a frustrating clinical course for patients and health care professionals. Despite huge research interest, a universally accepted and used definition of clinical criteria for the diagnosis of adhesive capsulitis is currently still lacking. This systematic review aimed to identify diagnostic values for clinical examinations tests used in the diagnosis of adhesive capsulitis.

EVIDENCE ACQUISITION

A total of 5 electronic databases (PubMed, Web of Science, Embase, Cochrane Central Register of Controlled Trials [CENTRAL] and PEDro) were searched for relevant studies from 2002 until October 2022 using the terms: "adhesive capsulitis AND diagnosis" and "frozen shoulder AND diagnosis." The Downs and Black Checklist (modified) was used to assess the risk of bias. The study protocol was prospectively registered at the International prospective register of systematic reviews (PROSPERO, CRD42022365993).

EVIDENCE SYNTHESIS

The initial database search identified 1799 studies, of which 9 (0.50%) were eventually included in the systematic review. Non-intrusive shoulder range of motion measurements in patients with adhesive capsulitis using the Kinect for Windows (Microsoft, Redmond, WA, USA) showed high correlation with clinical range of motion measurement. Two specific clinical tests, the affected-unaffected shoulder approach of the Coracoid Pain Test and the Distension Test in Passive External Rotation, were identified and presented excellent sensibility and specificity in the diagnosis of adhesive capsulitis, in their original study. Comparison between clinical tests was not possible due to the heterogeneity in clinical tools.

CONCLUSIONS

This systematic review identified several physical examination tests developed for the diagnosis of adhesive capsulitis but could not compare them nor advance a set of clinical diagnostic tests that are scientifically validated. Further research is warranted to obtain validation of clinical diagnosis tools for adhesive capsulitis.

A multi-center, single-blinded, randomized, parallel-group, superiority study to compare the efficacy of manipulation under anesthesia versus intra-articular steroid injection in the treatment of patients with frozen shoulder and a diagnosis of rotator cuff injury or tear by MRI: study protocol for a randomized controlled trial

BACKGROUND

Frozen shoulder (FS) is a common condition that can cause severe pain and limited range of motion in the shoulder joint. While intra-articular steroid injection has been shown to be an effective treatment for FS, manipulation under anesthesia (MUA) is an alternative treatment that has gained popularity in recent years. However, there is a lack of evidence regarding the effectiveness of MUA on FS patients with concomitant rotator cuff injury or tear. Though a few studies have shown that MUA is not associated with rotator cuff tears, and will not exacerbate the injury, more high-quality studies with bigger sample sizes are needed. Therefore, the aim of this multi-center, single-blinded, randomized, parallel-group, superiority study is to compare the efficacy of MUA versus intra-articular steroid injection in the treatment of FS patients with a diagnosis of rotator cuff injury or tear by MRI.

METHODS

A parallel, single-blinded, multi-center randomized controlled trial of 320 patients will be conducted at three hospitals of China. Eligible patients with frozen shoulder and rotator cuff injury or tear diagnosed by MRI will be randomly assigned to, in equal proportions, the manipulation under anesthesia group and the intra-articular steroid injection group via a central randomization system, undergoing a corresponding operation on day one and a sequent physical exercise for 14 days. The primary outcome is the comprehensive efficacy evaluation (total effective rate) and the change of Constant-Murley Score. Outcome assessors and data analysts will be blinded, and participants will be asked not to reveal their allocation to assessors.

DISCUSSION

This study aims to explore the superiority of manipulation under anesthesia in reducing pain and improving shoulder function in frozen shoulder patients accompanied with rotator cuff injury. To provide a scientific basis for the dissemination and application of manipulation under anesthesia, and a better knowledge for the role of MUA in the treatment of frozen shoulder accompanied with rotator cuff injury.

TRIAL REGISTRATION

Chictr.org.cn ChiCTR2200067122 . Registered on 27 December 2022. ChiCTR is a primary registry of the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) network and includes all items from the WHO Trial Registration data set in Trial registration.

Clinical and Biochemical Implications of Hyaluronic Acid in Musculoskeletal Rehabilitation: A Comprehensive Review

Hyaluronic acid (HA) naturally occurs as a biopolymer in the human body, primarily in connective tissues like joints and skin. Functioning as a vital element of synovial fluid, it lubricates joints, facilitating fluid movement and diminishing bone friction to protect articular well-being. Its distinctive attributes encompass notable viscosity and water retention capacities, ensuring flexibility and absorbing shock during motion. Furthermore, HA has gained significant attention for its potential benefits in various medical applications, including rehabilitation. Ongoing research explores its properties and functions, especially its biomedical applications in several clinical trials, with a focus on its role in improving rehabilitation outcomes. But the clinical and biochemical implications of HA in musculoskeletal rehabilitation have yet to be fully explored. This review thoroughly investigates the properties and functions of HA while highlighting its biomedical applications in different clinical trials, with a special emphasis on its role in rehabilitation. The presented findings provide evidence that HA, as a natural substance, enhances the outcomes of musculoskeletal rehabilitation through its exceptional mechanical and biochemical effects.

Increased Expression of Adipokines in Patients With Frozen Shoulder

BACKGROUND

Adipokines represent a spectrum of bioactive molecules that could modulate fibroblastic and inflammatory processes. The role of adipokines in the pathogenesis of frozen shoulder (FS), a common musculoskeletal disorder characterized by chronic inflammation, remains obscure.

PURPOSE

To evaluate whether adipokines contribute to the pathogenic mechanisms of FS and to evaluate any potential correlation of adipokines with patients' symptoms.

STUDY DESIGN

Controlled laboratory study.

METHODS

Shoulder capsule specimens were obtained from 10 patients with FS and 10 patients with shoulder instability (control group). The specimens were dyed using hematoxylin and eosin and immunohistochemically assessed with antibodies targeting adipokines, collagen I, collagen III, and tumor necrosis factor α. Immunoreactivity was graded from "no" to "strong" in a blinded manner. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) analysis was conducted. Before the surgery, patient-reported frequency of pain, severity of pain, stiffness, and shoulder range of motion were documented.

RESULTS

In comparison with the control group, patients with FS had significantly greater pain frequency, pain severity, and stiffness and more limited shoulder range of motion (P < .001). Hematoxylin and eosin- and Masson trichrome-stained samples from the FS group displayed hypercellularity and increased collagen fibers. Immunohistochemistry and RT-qPCR analyses indicated that expression of adipokines was significantly increased in FS capsules compared with the control group. The expression of collagen I, collagen III, and tumor necrosis factor α was also increased in FS capsules. No significant correlation was noted between adipokine expression and patient-reported outcomes in the control group, whereas in patients with FS, adiponectin expression was correlated with pain frequency (r = 0.78; P = .01) and stiffness (r = 0.73; P = .02). Visfatin was also correlated with pain frequency (r = 0.70; P = .02).

CONCLUSION/CLINICAL RELEVANCE

This study indicated a potential role for adipokines in the pathogenesis of FS and demonstrated a correlation between adipokine expression and patients' pain and stiffness.

Exploration of the clinical course and longitudinal correlations in frozen shoulder: The role of autonomic function, central pain processing, and psychological variables. A longitudinal multicenter prospective observational study

BACKGROUND

Altered central pain processing (CPP) and dysautonomia might play a role in the clinical course of frozen shoulder and psychological factors, like pain catastrophizing and hypervigilance, might influence clinical variables in frozen shoulder.

OBJECTIVES

To explore the clinical course of frozen shoulder regarding CPP, dysautonomia, pain catastrophizing, and hypervigilance and to explore whether longitudinal correlations between these outcomes and pain intensity were present.

DESIGN

prospective longitudinal observational study.

METHOD

Participants with frozen shoulder were recruited at hospitals and general practitioner practices and followed for 9 months. They completed six questionnaires (about demographics, shoulder pain and disability, pain intensity, pain catastrophizing, pain hypervigilance, and autonomic symptoms) and underwent tactile sensitivity (allodynia), pressure pain thresholds (hyperalgesia), temporal summation, and conditioned pain modulation during four timeframes (3-month intervals).

RESULTS

Initially, 149 participants with frozen shoulder were recruited and 88 completed all the measurements. An improvement from baseline to at least one follow-up measurement was found for shoulder pain and disability, pain intensity, pain catastrophizing, hypervigilance, and dysautonomia. A fair longitudinal correlation was found between pain intensity and catastrophizing and hypervigilance (r = 0.301-0.397). Poor longitudinal correlations were found between pain intensity and allodynia and hyperalgesia (r = -0.180-0.193), between pain catastrophizing and dysautonomia (r = 0.209) and between hypervigilance and hyperalgesia (r = -0.159).

CONCLUSION

Patients with frozen shoulder showed an early improvement that flattened with time in several pain and psychological variables over the course of 9 months. However, autonomic symptoms rather showed a late improvement over 9 months.

Efficacy of hydrodilatation in frozen shoulder: a systematic review and meta-analysis

INTRODUCTION

It is unclear whether hydrodilatation is beneficial in the management of frozen shoulder compared with other common conservative management modalities. This systematic review evaluates the efficacy of hydrodilatation for the management of frozen shoulder.

SOURCES OF DATA

A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An extensive search of PubMed, Embase, Scopus, Cochrane Central, Web of Science and CINAHL databases using multiple keyword combinations of 'shoulder', 'rotator', 'adhesive capsulitis', 'hydrodilatat*', 'distension' since inception of the databases to June 2023 was implemented.

AREAS OF AGREEMENT

Hydrodilatation leads to at least transient more marked improvements in shoulder disability and passive external rotation compared with intra-articular corticosteroid injections.

AREAS OF CONTROVERSY

Hydrodilatation improves passive external rotation in the longer term. Moreover, hydrodilatation may be a preferable option over manipulation under anaesthesia, given its lower cost and better patient convenience.

GROWING POINTS

Intensive mobilization after hydrodilatation is a promising adjuvant treatment option for patients suffering from a frozen shoulder.

AREAS TIMELY FOR DEVELOPING RESEARCH

Although current evidence suggests that hydrodilatation provides a transient improvement in disability in patients with frozen shoulder, its clinical relevance remains unclear. Further research is necessary to establish its role in the management of the condition.

Effectiveness of electrophysical agents in subjects with frozen shoulder: a systematic review and meta-analysis

PURPOSE

This systematic review with meta-analysis aimed to assess the effectiveness of electrophysical agents in improving pain, function, disability, range of motion, quality of life, perceived stiffness, and time to recovery in subjects with frozen shoulder (FS).

METHODS

A thorough search of MEDLINE, Cochrane Library, PEDro, and EMBASE yielded 1143 articles, of which 23 randomized controlled trials were included. Risk of bias (RoB) was assessed through Cochrane Risk of Bias 2 tool. The certainty of evidence was evaluated through the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).

RESULTS

The analysis included a total of 1073 subjects. None of the studies were judged as low RoB. Potentially clinically significant differences were observed in pain at 6 weeks and 5 months after extracorporeal shockwave therapy (ESWT), and in disability up to 3 months with laser therapy, albeit with uncertain results due to the high RoB and to the study heterogeneity. Ultrasound (US) therapy did not yield significant differences in any outcomes. The certainty of evidence was very low.

CONCLUSIONS

Based on the high heterogeneity and low quality and certainty of evidence, ESWT, laser, and US cannot be recommended for FS treatment. Caution should be exercised in interpreting the findings.

Relationship between pain and range of motion in frozen shoulder

Background

A frozen shoulder (FS) is characterized by pain and limited range of motion (ROM). Although physical assessment of ROM is important for diagnosing and staging FS, ROM cannot be accurately assessed in clinical practice because of pain and muscle contraction. This study aimed to measure changes in shoulder joint ROM before and after anesthesia (ΔROM) in patients with FS and investigate the factors affecting these changes.

Methods

This study included 54 patients (age, 55.6 ± 9.4 years; 17 males; disease duration, 6.6 ± 3.4 months) with FS before manipulation under transmission anesthesia. FS was defined as having a ROM in external rotation (ER) that was less than 50% of that in the unaffected shoulder. Pain at night and during motion was assessed using a numerical rating scale. Before anesthesia, the passive ROM of forward flexion (FF), abduction (AD), and ER were measured in the supine position. After confirming that the anesthesia was effective, passive ROM was measured again.

Results

The ROM in the FF, AD, and ER after anesthesia was significantly higher than that before anesthesia (P < .001). ΔROM in the FF, AD, and ER was significantly correlated with pain at night (r = 0.51, P < .001; r = 0.45, P < .001; and r = 0.39, P = .004, respectively). Furthermore, ΔROM in the ER was significantly correlated with pain during motion (r = 0.31, P = .023) and disease duration (r = -0.31, P = .021).

Conclusion

The ROM of the FS is susceptible to pain and muscle contraction. Interventions, such as physical therapy, may be recommended after pain relief.

Central sensitization syndrome in patients with rotator cuff tear: prevalence and associated factors

INTRODUCTION

A significant number of rotator cuff tear (RCT) patients developed chronic shoulder pain that did not correspond to physiological changes. Central sensitization syndrome (CSS) is a neurophysiological adaptation process that can result in hypersensitivity to peripheral stimuli. Although there is evidence of an association between CSS and musculoskeletal problems, no studies have focused on the association between CSS and RCT. The primary purpose of this study was to examine the prevalence of CSS in patients with RCT. The secondary purpose was to document the associated conditions and comorbidity that were associated with the CSS.

METHODS

This was a cross-sectional study of patients with RCT who completed the Central Sensitization Inventory (CSI). Patients with score of ≥ 40/100 were considered positive for CSS. Demographic and clinical data and CSI results were collected to analyze the prevalence and associated factors of CSS in RCT patients.

RESULTS

A total of 404 RCT patients were included, and the CSS prevalence was 39.4%. Compared to the non-CSS group, the CSS group had an odds ratio of 4.13 (95% CI, 2.70-6.32; p＜0.001) for ages 51-60, 3.07 (95% CI, 2.00-4.69; p＜0.001) for symptoms lasting more than 6 months, 6.08 (95% CI, 3.90-9.47; p＜0.001) for nonphysical laborers, 3.69 (95%CI, 2.42-5.61; p＜0.001) for long head of biceps (LHB) abnormality, 2.93 (95% CI, 1.93-4.45; p＜0.001) for concurrent shoulder stiffness, 4.82 (95% CI, 2.55-9.10; p＜0.001) for anxiety or panic episodes, and 2.11 (95% CI, 1.12, 4.00; p＜0.001) for depression.

CONCLUSIONS

The prevalence of CSS in patients with RCT was relatively high at 39.4%. The CSS was associated with higher age, female gender, and clinical findings of symptoms lasting over six months, nonphysical laborers, abnormal LHB, concurrent shoulder stiffness, anxiety, and depression.

Exploration of the clinical course of frozen shoulder: A longitudinal multicenter prospective study of functional impairments

BACKGROUND

Contradictory evidence exists regarding the clinical course of frozen shoulder (FS).

OBJECTIVES

To explore the clinical course of FS regarding disabilities, pain, range of motion (ROM), muscle strength, scapular upward rotation, and proprioception and to establish longitudinal correlations between these variables.

METHODS

Patients with FS were prospectively followed for 9 months at 3-month intervals. Assessment included the Disabilities of the Arm, Shoulder and Hand questionnaire; visual analogue scale for pain; an inclinometer for shoulder external rotation (ER), internal rotation (IR), flexion, and abduction ROM, and scapular upward rotation and proprioception, as well as handheld dynamometry for muscle strength in shoulder abduction, ER, and IR.

RESULTS

Initially, 149 patients (98 females; mean (SD) age 53 (9) years) were included, with 88 completing all follow-up assessments. Most variables showed early improvement in the clinical course of FS, particularly ER and IR at 90° abduction, which continued to improve from 6 to 9 months of follow-up. Associations were observed between disabilities and pain (r = 0.61), disabilities/pain and ROM (r=-0.62 to -0.59 and r=-0.47 to -0.39, respectively), disabilities/pain and muscle strength (r=-0.24 to -0.35 and r=-0.36 to -0.17, respectively), and between disabilities/pain and scapular upward rotation below shoulder level (r = 0.23 to 0.38 and r = 0.24 to 0.30, respectively). ROM correlated with muscle strength (r = 0.14 to 0.44), while both ROM and ER muscle strength correlated with scapular upward rotation below shoulder level (r=-0.37 to -0.23 and r=-0.17 to -0.12, respectively). Muscle strength correlated with scapular upward rotation above shoulder level (r = 0.28 to 0.38) and lift-off muscle strength correlated with joint repositioning (r=-0.17 to -0.15).

CONCLUSION

Almost all factors improved in the early phase (3-6 months) after baseline assessment, while ER and IR ROM at shoulder level continued to improve long term.

Vitamin C as a Potential Prophylactic Measure Against Frozen Shoulder in an In Vivo Shoulder Contracture Animal Model

BACKGROUND

Frozen shoulder is a common, painful, and movement-restricting condition. Although primary frozen shoulder is idiopathic, secondary frozen shoulder can occur after trauma or surgery. Prophylactic and therapeutic options are often unsatisfactory. Vitamin C (ascorbic acid) is a potent physiological antioxidant and likely inhibits the activation of nuclear factor κB, which plays a decisive role in inflammatory reactions.

HYPOTHESIS

Because of its anti-inflammatory effects, vitamin C may be valuable in the prevention of secondary frozen shoulder.

STUDY DESIGN

Controlled laboratory study.

METHODS

An in vivo shoulder contracture model was conducted by fixation of the right proximal limb of Sprague-Dawley rats. A treatment group (n = 8) receiving vitamin C orally was compared with a control group (n = 9) without vitamin C. The primary outcome was capsular thickness at the shoulder joint measured on magnetic resonance imaging (MRI) examination. Further histological examination was performed but was not statistically analyzed because of variability of the cutting plane through the glenoid.

RESULTS

Vitamin C treatment resulted in less thickening of the axillary fold of the operated shoulder at 2 of the 3 locations measured on MRI compared with untreated controls (insertion to the glenoid, P = .074; insertion to the humerus, P = .006; middle of the axillary recess, P = .008). The observed structural changes in histological examination corroborated the significant changes obtained from the MRI measurements.

CONCLUSION

Prophylactic vitamin C seemed to reduce the thickening of the axillary recess in secondary frozen shoulder in this preclinical study.

CLINICAL RELEVANCE

Vitamin C may be helpful as a noninvasive therapeutic measure to prevent secondary frozen shoulder (eg, within the context of surgery in the shoulder region or immobilization) or to treat primary frozen shoulder at an early stage. Further studies are required to evaluate the effect of this treatment in humans and the necessary dosage in humans.

Causal relationship between ischemic stroke and its subtypes and frozen shoulder: a two-sample Mendelian randomization analysis

Background

Previous epidemiological and other studies have shown an association between ischemic stroke (IS) and frozen shoulder (FS). However, the causal relationship between them remains unclear. Therefore, the present study aimed to investigate the causal relationship between IS and FS using a two-sample Mendelian randomization method.

Methods

Our research was divided into two stages: discovery and replication. The data were extracted from publicly available genome-wide association studies (GWAS). We selected a large sample of IS (n = 440, 328) and its subtypes (large-artery atherosclerotic stroke (LAS), cardioembolic stroke (CES), and stroke caused by small-vessel disease (SVS) and lacunar stroke (n = 254, 959) as exposure data. Additionally, we selected a large sample of FS as outcome data (n = 451, 099). Inverse variance weighting (IVW) was applied as the primary analysis method. The weighted median, MR-Egger, simple model, and weighted model were used as complementary analysis methods to assess causal effects. Moreover, heterogeneity was analyzed using Cochran's Q-test with IVW and MR-Egger. The MR-Egger intercept and MR-PRESSO analysis methods were used for pleiotropy testing. The stability of the results was also assessed using a leave-one-out analysis.

Results

In the discovery stage, the IVW approach revealed an odds ratio (OR) of 1.207 with a 95% confidence interval (CI) of 1.027-1.417 and a P-value of 0.022. This suggests a causal association between IS levels and an increased risk of FS. In the subtype studies of IS, the findings were negative. However, during the replication stage, a significant causal link was found between selected lacunar strokes and FS with an OR of 1.252, a 95% CI of 1.105-1.419, and a P-value of 0.0004. All studies had no pleiotropy or heterogeneity, and the findings were robust.

Conclusions

Our study confirmed the causal relationship between any IS level and increased risk of FS. Furthermore, the same results were obtained in the replication stage with lacunar stroke as an exposure factor. However, there was no direct causal relationship between the subtypes of IS and FS. Our study provides theoretical support for shoulder care for patients with IS.

Deficits in the thalamocortical pathway associated with hypersensitivity to pain in patients with frozen shoulder

Background and purpose

Frozen shoulder (FS) is a chronic pain condition and has been shown to be associated with pain sensitization. However, the underyling brain mechanisms remain unclear. Here, we aimed to explore brain alterations and their association with pain sensitization in patients with FS.

Materials and methods

A total of 54 FS patients and 52 healthy controls (HCs) were included in this study. Here, we applied both structural and functional magnetic resonance imaging (MRI) techniques to investigate brain abnormalities in FS patients. Voxel-wise comparisons were performed to reveal the differences in the gray matter volume (GMV) and amplitude of low-frequency fluctuation (ALFF) between FS patients and HCs. Furthermore, the region of interest (ROI) to whole-brain functional connectivity (FC) was calculated and compared between groups. Finally, Pearson's correlation coefficients were computed to reveal the association between clinical data and brain alterations.

Results

Four main findings were observed: (1) FS patients exhibited decreased thalamus GMV, which correlated with pain intensity and pain threshold; (2) relative to HCs, FS patients exhibited a higher level of ALFF within the anterior cingulate cortex (ACC) and the thalamus; (3) FS patients exhibited a significant increase in Tha-S1 FC compared to HCs; and (4) the effect of thalamus GMV on pain intensity was mediated by pain threshold in FS patients.

Conclusion

The dysfunctional thalamus might induce pain hypersensitivity, which further aggravates the pain in FS patients.

Living with frozen shoulder. 'Here are the risks. I want the injection'. An interpretative phenomenological analysis

BACKGROUND

Frozen shoulder is a disabling condition characterised by severe pain and loss of shoulder movement and may affect up to 5% of the population. Qualitative research documents debilitating pain and how treatment to reduce pain is a priority for people diagnosed with frozen shoulder. Corticosteroid injections are a principal treatment to reduce the pain of frozen shoulder, however little is known about the patient experience.

OBJECTIVES

This study aims to address this gap in the knowledge by exploring the lived experience of people with frozen shoulder who have undergone an injection and to highlight other novel findings.

DESIGN

This is a qualitative study using interpretative phenomenological analysis. One-to-one, semi-structured interviews were conducted with seven people diagnosed with frozen shoulder who had received a corticosteroid injection as part of their management.

METHODOLOGY

A purposive sample of participants were interviewed via MSTeams™ due to Covid-19 restrictions. Data was collected through semi-structured interviews and analysed in accordance with interpretive phenomenological analysis methods.

RESULTS

Three group experiential themes were identified: the dilemma surrounding injections; the challenges of understanding the causes of frozen shoulder; the impact on self and others.

CONCLUSION

Participants conveyed a strong desire in seeking a corticosteroid injection whilst seemingly dismissing the risks. A novel concept was illuminated as frozen shoulder seemed inextricably linked with the ageing process, which negatively impacted body-image. The impact on others is driven by a sense of the unfamiliar nature of illness and it is incumbent on healthcare professionals to seek opportunities to explore the individual's beliefs.

Analysis of risk factors for advanced age in patients with frozen shoulder

OBJECTIVE

To explore the risk factors of elderly patients with frozen shoulder.

METHODS

262 cases of scapulohumeral periarthritis treated in our hospital from January 2020 to December 2020 were analyzed retrospectively. According to the age of patients, patients younger than 60 years old were divided into middle-aged group (101 cases), patients between 60 and 75 years old were divided into old-aged group (91 cases), and patients ≥ 75 years old were divided into old-aged group (70 cases). The general demographic data and clinical data of the three groups were compared. Visual analogue scale (VAS) was used to evaluate the degree of pain. Finally, the dependent variable is set as whether the onset age of scapulohumeral periarthritis patients is advanced. Univariate and multivariate Logistic regression was used to analyze the risk factors of frozen shoulder patients at an advanced age.

RESULTS

There were no significant differences in general demographic data, fixed position, hypertension history, smoking history, drinking history, supraspinatus muscular atrophy and physical exercise among the three groups (all P > 0.05). The course of disease, diabetes, surgical treatment, pain degree, operation time, cholecystitis, coronary heart disease, pain degree three months after operation and cervical spondylosis in the elderly group were all higher than those in the middle-aged group and the elderly group, and the differences were statistically significant (all P < 0.05). The course of scapulohumeral periarthritis, the degree of pain and the degree of pain 3 months after operation in the elderly group were higher than those in the middle-aged group, with significant differences (all P < 0.05). Univariate Logistic regression analysis showed that the risk factors of scapulohumeral periarthritis in the elderly included diabetes mellitus (OR = 3.067, 95% CI 1.881-4.587, P < 0.001), operative treatment (OR = 3.076, 95% CI 1.365-6.765, P = 0.006), VAS score (OR = 2.267, 95% CI 1.117-3.887, P = 0.013), operation time (OR = 1.537, 95% CI 1.305-2.579, P < 0.001), cholecystitis (OR = 2.143, 95% CI 1.019-4.876, P = 0.023), coronary heart disease(OR = 3.128, 95% CI 1.428-7.019, P = 0.005), VAS at 3 months after operation (OR = 1.537, 95% CI 0.786-2.635, P = 0.002), and cervical spondylosis(OR = 1.162, 95% CI 1.029-1.321, P = 0.012). Multivariate logistic regression analysis showed that the risk factors for the onset of the disease at advanced age included fatty infiltration (OR = 4.021, 95% CI 2.981-9.682, P < 0.001), surgical treatment (OR = 4.109, 95% CI 1.419-7.832, P = 0.008), VAS score (OR = 3.081, 95% CI 1.042-7.931, P = 0.046) and operation time (OR = 1.537, 95% CI 1.305-2.579, P < 0.001).

CONCLUSION

Risk factors of frozen shoulder at advanced age include fat infiltration, surgical treatment, VAS score and surgical time. In clinical practice, we should refer to the above indicators to help patients with early medical intervention and prevent their onset.