Adhesive capsulitis: An age related symptom of metabolic syndrome and chronic low-grade inflammation?

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.

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.

Differences in biomechanical and metabolic factors between patients with frozen shoulder and asymptomatic individuals. A cross-sectional study

BACKGROUND

the pathogenesis of frozen shoulder (FS) is thought to be one of inflammation and fibrosis possibly influenced by hyperglycemia. Biomechanical changes of the shoulder joint in terms of muscle strength, scapular kinematics and proprioception might occur in FS.

OBJECTIVES

to compare muscle strength, scapular kinematics, proprioception, and blood glucose levels within patients with FS and to asymptomatic individuals.

DESIGN

cross-sectional study.

METHOD

Thirty-five patients with FS and 35 asymptomatic age and gender-matched individuals underwent physical assessment to determine muscle strength (abduction, external and internal rotation), scapular kinematics (both visually and with a plurimeter), proprioception (joint position sense), and blood glucose level.

RESULTS

Patients with FS showed a decrease in muscle strength in their affected shoulder compared to both the unaffected shoulder and asymptomatic individuals. Significant differences were found between the affected and unaffected shoulder in the FS group and between groups (FS versus controls) in scapular upward rotation (plurimeter) at 30° and 60° abduction. No difference in scapular kinematics (visual observation), proprioception, and blood glucose levels was found neither between shoulders in the FS group nor between groups.

CONCLUSION

A clinically relevant difference in muscle strength and increase in scapular upward rotation were found in the affected shoulder of patients with FS compared to their unaffected side and controls. However, no evidence of different levels of scapular kinematics (visual observation), proprioception, and blood glucose levels in the affected shoulder compared to the unaffected shoulder or controls is lacking.

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.

An Updated Overview of Risk Factors for Shoulder Stiffness

A painful reduction in shoulder mobility, known as "shoulder stiffness", can occur both as a primary idiopathic condition and as a secondary condition, for example, following surgical procedures. Various factors can contribute to the development of primary shoulder stiffness. In this review we summarize the pathophysiological mechanisms, genetic influences, endocrine disorders, metabolic conditions, as well as other diseases and medical-therapeutic approaches that might have an impact on the development of primary shoulder stiffness.

Progress in studying the impact of hyperlipidemia and statins on rotator cuff injury and repair

This review delves into the intersection of two prevalent conditions, hyperlipidemia and rotator cuff injuries, both of which bear substantial healthcare burdens. Our investigation begins with an exploration of rotator cuff injuries, common musculoskeletal disorders that severely impair shoulder functionality and quality of life. These injuries are notably pervasive among sports enthusiasts and the older adult, with an incidence rate estimated at 5-10% in the general population. Despite their widespread occurrence and the diverse, multifactorial etiological factors, effective treatment strategies remain elusive. We then examine hyperlipidemia, a metabolic disorder affecting approximately 40% of the global adult population. Characterized by elevated levels of cholesterol and triglycerides, hyperlipidemia can precipitate severe cardiovascular complications and presents a significant socioeconomic burden. Although current management strategies encompass lifestyle modifications and pharmacological interventions, the condition remains a formidable health challenge. Central to this review is the exploration of a potential association between hyperlipidemia and rotator cuff injuries. We aim to synthesize the current understanding of hyperlipidemia's role in the pathophysiology of rotator cuff injuries, thereby offering fresh insights into their common etiological underpinnings, potential therapeutic targets, and drugs, such as Statins. The influence of other lipid-lowering therapeutics on tendon health is also considered, and further research into the molecular pathways and potential therapeutic benefits of these drugs is required. This pursuit aligns with broader efforts to enhance patient outcomes, minimize healthcare burdens, and contribute to the global understanding of these prevalent conditions.

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 combined strategies of physical activity, diet and sleep disorders as treatment in patients with chronic shoulder pain. A systematic review

Introduction: The objective of this systematic review was to analyze the existing scientific evidence on the influence of dietary strategies, exercise, and sleep disorders on the symptomatology of patients with chronic shoulder pain, as well as to assess the methodological quality of the literature collected. Methods: The selection criteria were as follows: we included randomized controlled clinical trials written in English that investigated the effects of such interventions in patients with chronic shoulder pain and excluded studies where pre-operative rehabilitation or rehabilitation combined with corticosteroid injections was performed. We searched six databases Pubmed, Cochrane Library, Web of Science, CINAHL, Sportdiscus and Scopus, using the keywords "shoulder pain," "fasting," "physical therapy modalities," "rehabilitation," "exercise," "circadian clocks," and "chronic pain" to select randomized controlled clinical trials conducted in humans and written in English. The last search was conducted on 24/01/2023. (PROSPERO:CRD42023379925). Results: We used the tool proposed by the Cochrane Handbook to assess the risk of bias in the included studies of the 17 studies included, nine had a high risk of bias, two studies had an unclear risk of bias, and the remaining six studies had a low risk of bias. A total of 17 articles were selected, including 10 studies that showed a positive influences of exercise on chronic shoulder pain and five studies that showed a negative influence of sleep disorders on this patient profile. The remaining two articles analyzed the influence of nutritional strategies and metabolic problems in patients with chronic shoulder pain. The total sample size of the 17 included articles amounted to 9,991 individuals. Discussion: Studies confirm that exercise generates a hypoalgesic effect that improves chronic shoulder pain, functionality, and quality of life. Although dietary strategies and sleep disorders are known to influence chronic shoulder pain, there is a lack of studies that conduct interventions on these problems to assess how chronic shoulder pain varies.

Is there any benefit of adding a central nervous system-focused intervention to a manual therapy and home stretching program for people with frozen shoulder? A randomized controlled trial

BACKGROUND

Frozen shoulder (FS) is a highly disabling pathology of poorly understood etiology, which is characterized by the presence of intense pain and progressive loss of range of motion. The aim of this study was to evaluate the effect of adding a central nervous system (CNS)-focused approach to a manual therapy and home stretching program in people with FS.

METHODS

A total of 34 patients with a diagnosis of primary FS were randomly allocated to receive a 12-week manual therapy and home stretching program or manual therapy and home stretching program plus a CNS-focused approach including graded motor imagery and sensory discrimination training. The Shoulder Pain and Disability Index score, self-perceived shoulder pain (visual analog scale score), shoulder range of motion, and the Patient-Specific Functional Scale score were measured at baseline, after a 2-week washout period just before starting treatment, after treatment, and at 3 months' follow-up.

RESULTS

No significant between-group differences in any outcome were found either after treatment or at 3 months' follow-up.

CONCLUSION

A CNS-focused approach provided no additional benefit to a manual therapy and home stretching program in terms of shoulder pain and function in people with FS.

Diabetes as a risk factor for the onset of frozen shoulder: a systematic review and meta-analysis

OBJECTIVE

Summarise longitudinal observational studies to determine whether diabetes (types 1 and 2) is a risk factor for frozen shoulder.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

MEDLINE, Embase, AMED, PsycINFO, Web of Science Core Collection, CINAHL, Epistemonikos, Trip, PEDro, OpenGrey and The Grey Literature Report were searched on January 2019 and updated in June 2021. Reference screening and emailing professional contacts were also used.

ELIGIBILITY CRITERIA

Longitudinal observational studies that estimated the association between diabetes and developing frozen shoulder.

DATA EXTRACTION AND SYNTHESIS

Data extraction was completed by one reviewer and independently checked by another using a predefined extraction sheet. Risk of bias was judged using the Quality In Prognosis Studies tool. For studies providing sufficient data, random-effects meta-analysis was used to derive summary estimates of the association between diabetes and the onset of frozen shoulder.

RESULTS

A meta-analysis of six case-control studies including 5388 people estimated the odds of developing frozen shoulder for people with diabetes to be 3.69 (95% CI 2.99 to 4.56) times the odds for people without diabetes. Two cohort studies were identified, both suggesting diabetes was associated with frozen shoulder, with HRs of 1.32 (95% CI 1.22 to 1.42) and 1.67 (95% CI 1.46 to 1.91). Risk of bias was judged as high in seven studies and moderate in one study.

CONCLUSION

People with diabetes are more likely to develop frozen shoulder. Risk of unmeasured confounding was the main limitation of this systematic review. High-quality studies are needed to confirm the strength of, and understand reasons for, the association.

PROSPERO REGISTRATION NUMBER

CRD42019122963.

Current concepts in the diagnosis and treatment of adhesive capsulitis: role of diagnostic imaging and ultrasound-guided interventional procedures

Adhesive capsulitis is a common cause of painful shoulder, characterized by pain and restricted range of motion of the glenohumeral joint. With a well-known clinical presentation, and an increasing understanding of its clinical and radiologic features, early diagnosis of adhesive capsulitis is becoming a reality. Although often treated conservatively, for refractory cases arthroscopic release and open capsulotomy have been the only therapeutic option for a long time. Therefore, in the last years, a particular effort was put into the development of novel minimal-invasive techniques capable of pain relief and functional range improvement of the glenohumeral joint. The purpose of this literature review is to report the main updates on diagnosis and treatment for adhesive capsulitis with a focus on imaging diagnosis techniques and novel minimally invasive ultrasound-guided treatments. Results showed that ultrasound-guided procedures come with a high success rate in terms of pain reduction and improved range of motion, thus making the ultrasound a unique tool capable of giving the operator real-time diagnostic information confirming the clinical suspicion, and subsequently performing an interventional procedure.

Understanding the clinical profile of patients with frozen shoulder: a longitudinal multicentre observational study

INTRODUCTION

There is a large diversity in the clinical presentation of frozen shoulder (FS) and the clinical outcome is not always satisfactory. The aim of the current study was to examine to what extent range of motion (ROM) limitation, metabolic factors (diabetes mellitus and thyroid disorders), autonomic symptoms and pain sensitivity may contribute to the prognosis in terms of shoulder pain and disability and quality of life in patients with FS.

METHODS

Patients with stage 1 or 2 FS were longitudinally followed-up during 9 months after baseline assessment. They completed six questionnaires and underwent quantitative sensory testing (pressure pain thresholds, temporal summation and conditioned pain modulation) and ROM assessment.

RESULTS

One hundred and forty-nine patients with FS were initially recruited and 121 completed at least one follow-up measurement. Shoulder pain and disability improved over time and diabetes mellitus was found to be a prognostic factor for final outcome. Several domains of quality of life also improved over time and external rotation ROM, diabetes mellitus, thyroid disorder and autonomic symptoms were found to be prognostic factors for final outcome. These prognostic factors explained 2.5%-6.3% of the final outcome of shoulder pain and disability and quality of life.

DISCUSSION AND CONCLUSION

In patients with FS, prognostic variables were able to predict different outcomes, indicating that outcomes in this population can be variable-dependent. Other variables not explored in this study might contribute to the prognosis of patients with FS, which should be investigated in future research. In clinical practice, baseline assessment of prognostic factors and focusing on a more holistic approach might be useful to inform healthcare practitioners about progression of patients with FS during a 9-month period.

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.

Autonomic Nervous System Function and Central Pain Processing in People With Frozen Shoulder: A Case-control Study

OBJECTIVES

The pathophysiology of a frozen shoulder (FS) is thought to be related to chronic inflammation. Chronic inflammation may disturb the immune system and consequently the nervous system as part of an overarching system. The aim of this study was to determine the presence of disturbed autonomic nervous system function and altered central pain processing (CPP) in patients with FS. Secondarily, the presence of psychological variables (catastrophizing and hypervigilance) and self-reported associated symptoms of altered CPP in patients with FS were investigated.

METHODS

Patients with FS and healthy controls completed the Composite Autonomic Symptom Score (autonomic function) and underwent quantitative sensory testing to assess tactile sensitivity (ie, allodynia), pressure pain thresholds (PPTs, ie, hyperalgesia), temporal summation of pain, and Conditioned Pain Modulation (CPM). Psychological issues were explored with the Pain Catastrophizing Scale and the Pain Vigilance and Awareness Questionnaire, and self-reported symptoms associated with altered CPP were determined with the Central Sensitization Inventory.

RESULTS

Thirty-two patients with FS and 35 healthy controls were analyzed in the study. Patients with FS showed more self-reported autonomic symptoms and symptoms of altered CPP, higher levels of pain catastrophizing and hypervigilance, and are more sensitive to tactile touches and mechanical pressure compared with controls.

DISCUSSION

On the basis of the effect sizes, between-group differences in allodynia, hyperalgesia, catastrophizing, and hypervigilance were clinically relevant, but only local allodynia, hyperalgesia, catastrophizing, and hypervigilance were statistically different. Therefore, obvious altered CPP was not present at the group level in patients with FS compared with controls.

A Review on Current Notion in Frozen Shoulder: A Mystery Shoulder

Frozen shoulder (FS) is a common condition affecting the population between the ages of 30 and 60; the causative agent is idiopathic, sedentary lifestyle, post-traumatic, or secondary to any pathological conditions. The pathology of FS is characterized by cytokine-mediated synovial inflammation with fibroblastic proliferation. The clinical features of FS vary depending on the phase in which the individual is present. The common clinical features are pain, and reduction in the range of motion in the capsular pattern. The available treatment options are medical therapy such as corticosteroid injection, physical therapy, joint mobilization, joint mobilization under anesthesia, and mirror therapy. When all the conservative methods fail then surgical procedures are used which include the surgical release of the restriction formed in the capsule. In conclusion, steroid injection along with physical therapy shows significant improvement in the range of motion and reduction in pain in the shoulder.

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.

Post-surgical physiotherapy in frozen shoulder: A review

Despite its prevalence, the optimal management of frozen shoulder is unclear. A range of conservative measures are often undertaken with varying degrees of success. In cases of severe and persistent symptoms, release procedures which could include any combination of manipulation under anaesthetic, arthroscopic capsular release or hydrodilatation are frequently offered, none of which has been shown to offer superior outcome over the others. When surgical release is performed a period of rehabilitation is normally recommended but no best practice guidelines exist resulting in considerable variations in practice which may or may not directly affect patient outcome. During this narrative review, we hypothesise that these differing responses to treatment (both conservative and surgical options) are potentially the result of different causal mechanisms for frozen shoulder and may also suggest that post-release rehabilitation may need to take this into account.

Using Nonlinear Vibroartrographic Parameters for Age-Related Changes Assessment in Knee Arthrokinematics

Changes in articular surfaces can be associated with the aging process and as such may lead to quantitative and qualitative impairment of joint motion. This study is aiming to evaluate the age-related quality of the knee joint arthrokinematic motion using nonlinear parameters of the vibroarthrographic (VAG) signal. To analyse the age-related quality of the patellofemoral joint (PFJ), motion vibroarthrography was used. The data that were subject to analysis represent 220 participants divided into five age groups. The VAG signals were acquired during flexion/extension knee motion and described with the following nonlinear parameters: recurrence rate (RR) and multi-scale entropy (MSE). RR and MSE decrease almost in a linear way with age (main effects of group p<0.001; means (SD): RR=0.101(0.057)−0.020(0.017); and MSE=20.9(8.56)−13.6(6.24)). The RR post-hoc analysis showed that there were statistically significant differences (p<0.01) in all comparisons with the exception of the 5th−6th life decade. For MSE, statistically significant differences (p<0.01) occurred for: 3rd−7th, 4th−7th, 5th−7th and 6th life decades. Our results imply that degenerative age-related changes are associated with lower repeatability, greater heterogeneity in state space dynamics, and greater regularity in the time domain of VAG signal. In comparison with linear VAG measures, our results provide additional information about the nature of changes of the vibration dynamics of PFJ motion with age.

A Central Nervous System Focused Treatment Program for People with Frozen Shoulder: A Feasibility Study

Background: Frozen shoulder (FS) is a highly disabling pathology of poorly understood etiology, which is characterized by the presence of intense pain and progressive loss of range of motion (ROM). The aim of this study is to evaluate the feasibility and clinical impact of a CNS-focused treatment program for people with FS. Methods: 10 subjects with primary FS received a 10-week CNS-focused intervention including sensory discrimination training and graded motor imagery techniques delivered as clinic sessions (60 min) and home therapy (30 min five times per week). Measurements were taken at baseline, after a 2-week “washout” period, after treatment, and at three months follow-up. The Shoulder Pain and Disability Index (SPADI) was the primary outcome. Secondary measures were feasibility-related outcomes, self-reported shoulder pain, active and passive range of motion, two-point discrimination threshold (TPDT), left/right judgement task (LRJT), fear-avoidance (Tampa Scale for Kinesiophobia), pain catastrophization (Pain Catastrophizing Scale), and pain sensitization (Central Sensitization Inventory). A Student’s t-test was used to assess the “washout” period. A repeated measure analysis of variance (ANOVA) was used to evaluate within-subjects’ differences for all outcome measures in the different assessment periods and a pairwise analysis was used to compare between the different assessment points. Statistical significance was set at p < 0.05. Results: 70% of participants completed the treatment. No significant changes were found after “washout” period except for TPDT (p = 0.02) and SPADI (p = 0.025). Improvements in self-reported shoulder pain (p = 0.028) and active shoulder flexion (p = 0.016) were shown after treatment (p = 0.028) and follow-up (p = 0.001) and in SPADI at follow-up (p = 0.008). No significant changes were observed in TPDT, LRJT, fear-avoidance, pain catastrophization, and pain sensitization. Conclusions: a CNS-focused treatment program might be a suitable approach to improve pain and disability in FS, but further research is needed to draw firm conclusions.

Does the Presence of Metabolic Syndrome Alter Serum Uric Acid Concentrations, Pain, and Well-Being in Patient with Chronic Musculoskeletal Pain?

Objective: To compare serum uric acid concentrations, pain and well-being in patients having chronic musculoskeletal pain with and without MetS, and investigate cut-off values. Methods: Patients having chronic musculoskeletal pain with (MetS group, n=48) and without MetS (control group, n=52) were included. The serum uric acid concentration, pain intensity, body composition, physical activity level, quality of life, and psychological status were evaluated by a uric acid blood test, Visual Analogue Scale, Bio-impedance Analyzer, International Physical Activity Questionnaire-7 (IPAQ-7), Nottingham Health Profile, and Hospital Anxiety and Depression Scale, respectively. Results: Uric acid level, fat mass, waist/hip ratio were found higher in the MetS group in comparison to the control group (P

Comparison of Gene Expression of Inflammation- and Fibrosis-Related Factors Between the Anterior and Posterior Capsule in Patients With Rotator Cuff Tear and Shoulder Stiffness

Background

Arthroscopic capsular release is an effective treatment for refractory shoulder stiffness, yet there are no basic studies that can explain the extent of the release.

Purpose

This study aimed to compare the genetic expression of inflammation- and fibrosis-related factors between the anterior and posterior capsules in patients with shoulder stiffness and rotator cuff tear.

Study Design

Descriptive laboratory study.

Methods

Enrolled in this study were 35 patients who underwent arthroscopic capsular release for shoulder stiffness along with the rotator cuff repair. Anterior and posterior glenohumeral joint capsular tissues were obtained during the capsular release. For the control tissue, anterior capsule was obtained from 40 patients without stiffness who underwent arthroscopic rotator cuff repair. The gene expression of collagen types I and III, fibronectin, extracellular matrix, basic fibroblast growth factor, transforming growth factor-β, connective tissue growth factor, matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, intercellular adhesion molecule 1, interleukin 1, and tumor necrotizing factor-α were analyzed using real-time reverse transcription polymerase chain reaction. Differences in gene expression between the anterior capsule, the posterior capsule, and the control tissue were compared with the Kruskal-Wallis test.

Results

The expression levels of collagen types I and III were significantly higher in the anterior capsule with stiffness com (pared with both the posterior capsule with stiffness (P = .010 for both) and the control (P = .038 and .010, respectively). The levels of fibronectin, MMP-2, and MMP-9 in the anterior capsule were significantly higher than in both the posterior capsule (P = .013, .003, and .006, respectively) and the control (P = .014, .003, and .005, respectively).

Conclusion

Genetic analysis of the shoulder capsule revealed that more fibrogenic processes occur in the anterior capsule compared with the posterior capsule in patients with shoulder stiffness.

Clinical Relevance

Capsular release for shoulder stiffness should be more focused on the anterior capsule than on the posterior capsule.

An overview of effective and potential new conservative interventions in patients with frozen shoulder

Frozen shoulder (FS) is a pathology that is difficult to understand and difficult to manage. Over the last ten years, contradictory and new evidence is provided regarding the recovery and its natural course. This narrative review provides new information about the diagnosis and conservative treatment of patients with FS and ongoing research hypotheses that might provide new insights in the pathology and treatment options. FS has a characteristic course. People with Diabetes Mellitus and thyroid disorders have a higher risk of developing a FS. The diagnosis FS is based on pattern recognition and physical examination. Additionally, 'rule-in' and 'rule-out' criteria can be used to increase the likelihood of the frozen shoulder diagnosis. Recommended and most common physical therapy interventions are mobilization techniques and exercises, in which tissue irritability can guide its intensity. In addition, physical therapy is often complementary with patient education and pharmacotherapy. The latest evidence-based practice related to FS is proprioceptive neuromuscular facilitation and mirror therapy. In addition, interventions like pain neuroscience education, high-intensity interval training and lifestyle changes are still hypothetical. Finally, better insight in the involvement of biochemical processes, function of myofibroblasts and matrix metalloproteinases can provide better understanding in the pathophysiology and will be addressed in current review.

A Comprehensive View of Frozen Shoulder: A Mystery Syndrome

Frozen shoulder is a common epidemiological affliction. Data acquired from people who suffer from this type of damage in other joints such as the hip, wrist and ankle also exist; although these syndromes are less common. Treatment for frozen shoulder is primarily physical (physiotherapy, manual therapy), secondary medical (corticosteroid injections) and finally surgical but with limited success. The difficulty in treating this type of condition successfully lies in the lack of knowledge about the risk factors involved and the pathophysiology underlying this mysterious syndrome. This review gives an overview of the current scientific position of frozen shoulder in terms of evolutionary factors, etiology, the different mechanisms of action involved, current treatment options and other possible interventions based on recent discoveries of pathophysiological mechanisms. The overall objective is to clarify several unknown aspects of a syndrome that affects up to 5% of the world's population.

The presence of gastroesophageal reflux disease increases the risk of developing postoperative shoulder stiffness after arthroscopic rotator cuff repair

BACKGROUND

Postoperative shoulder stiffness (SS) after arthroscopic rotator cuff (RC) repair has been reported with a variable incidence, and numerous preoperative risk factors have been described. This prospective study aimed to document the incidence of postoperative SS and to evaluate the role of preoperative risk factors in the development of this complication, with a special focus on the role of gastroesophageal reflux disease (GERD).

METHODS

Preoperative risk factors for SS were prospectively evaluated in 237 consecutive patients undergoing arthroscopic single-row RC repair. The presence of GERD was evaluated with the GerdQ diagnostic tool. Postoperative SS was diagnosed according to the criteria described by Brislin et al in 2007.

RESULTS

The incidence of postoperative SS was 8.02%. The presence of GERD was significantly associated with the development of postoperative SS (odds ratio [OR], 5.265; 95% confidence interval [CI], 1.657-1.731; P = .005). Older age (OR, 0.896; 95% CI, 0.847-0.949; P < .001), male sex (OR, 0.126; 95% CI, 0.0252-0.632; P = .012), and number of pregnancies (OR, 0.47; 95% CI, 0.228-0.967; P = .040) emerged as protective factors.

CONCLUSIONS

The presence of GERD significantly influences the development of postoperative SS after arthroscopic single-row RC repair. An underlying aspecific proinflammatory condition, characterized by increased expression of tumor necrosis factor α and transforming growth factor β, and disorders in retinoid metabolism are hypotheses that could explain this previously unknown association. The documented incidence of postoperative SS falls within previously reported ranges, with women being significantly more affected than men.

The puzzling pathophysiology of frozen shoulders - a scoping review

Purpose

The pathophysiology of frozen shoulders is a complex and multifactorial process. The purpose of this review is to scope the currently available knowledge of the pathophysiology of frozen shoulders.

Methods

A systematic search was conducted in Medline, Embase and the Cochrane library. Original articles published between 1994 and October 2020 with a substantial focus on the pathophysiology of frozen shoulders were included.

Results

Out of 827 records, 48 original articles were included for the qualitative synthesis of this review. Glenohumeral capsular biopsies were reported in 30 studies. Fifteen studies investigated were classified as association studies. Three studies investigated the pathophysiology in an animal studies. A state of low grade inflammation, as is associated with diabetes, cardiovascular disease and thyroid disorders, predisposes for the development of frozen shoulder. An early immune response with elevated levels of alarmins and binding to the receptor of advance glycation end products is present at the start of the cascade. Inflammatory cytokines, of which transforming growth factor-β1 has a prominent role, together with mechanical stress stimulates Fibroblast proliferation and differentiation into myofibroblasts. This leads to an imbalance of extracellular matrix turnover resulting in a stiff and thickened glenohumeral capsule with abundance of type III collagen.

Conclusion

This scoping review outlines the complexity of the pathophysiology of frozen shoulder. A comprehensive overview with background information on pathophysiologic mechanisms is given. Leads are provided to progress with research for clinically important prognostic markers and in search for future interventions.

Level of evidence

Level V.

Comparison of Clinical Outcomes between Idiopathic Frozen Shoulder and Diabetic Frozen Shoulder After a Single Ultrasound-Guided Intra-Articular Corticosteroid Injection

There is no consensus on the use of intra-articular corticosteroid injections in diabetic frozen shoulder (FS). Thus, we aimed to compare clinical outcomes after intra-articular corticosteroid injections in patients with diabetic FS and idiopathic FS. Data collected from 142 FS patients who received glenohumeral joint intra-articular corticosteroid injections were retrospectively reviewed. Thirty-two patients were diagnosed with diabetic FS and 110 patients with idiopathic FS. Data including visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES) score, subjective shoulder value (SSV), and passive range of motion (ROM) were compared before the injection and at 3, 6, and 12 weeks after the injection. There were significant improvements in all outcomes (p < 0.001 for all parameters) through 12 weeks in both groups. There were no significant differences in all outcomes, except for ASES scores, between both groups at 3 weeks. However, there were significant differences in VAS score, SSVs, ASES scores, and passive ROMs, except for angle of abduction, between the two groups at 6 weeks and 12 weeks after injection. A single intra-articular steroid injection can be used as a conservative treatment for diabetic FS, but less effective than for idiopathic FS.

Pathomechanics Underlying Femoroacetabular Impingement Syndrome: Theoretical Framework to Inform Clinical Practice

Over the last decade, there has been a marked increase in attention to, and interest in, femoroacetabular impingement syndrome (FAIS). Despite continued efforts by researchers and clinicians, the development, progression, and appropriate treatment of FAIS remains unclear. While research across various disciplines has provided informative work in various areas related to FAIS, the underlying pathomechanics, time history, and interaction between known risk factors and symptoms remain poorly understood. The purpose of this perspective is to propose a theoretical framework that describes a potential pathway for the development and progression of FAIS. This paper aims to integrate relevant knowledge and understanding from the growing literature related to FAIS to provide a perspective that can inform future research and intervention efforts.

Is there an association between metabolic syndrome and rotator cuff-related shoulder pain? A systematic review

Objectives

Rotator cuff-related shoulder pain (RCRSP) is a common upper limb complaint. It has been suggested that this condition is more common among people with cardiometabolic risk factors. This systematic review has synthesised evidence from case–control, cross-sectional and cohort studies on the association between metabolic syndrome (MetS) and RCRSP.

Design and data sources

Five medical databases (MEDLINE, EMBASE, SCOPUS, CINAHL and AMED) and reference checking methods were used to identify all relevant English articles that considered MetS and RCRSP. Studies were appraised using the Newcastle-Ottawa Scale (NOS). Two reviewers performed critical appraisal and data extraction. Narrative synthesis was performed via content analysis of statistically significant associations.

Results

Three cross-sectional, two case–control and one cohort study met the inclusion criteria, providing a total of 1187 individuals with RCRSP. Heterogeneity in methodology and RCRSP or MetS definition precluded a meaningful meta-analysis. Four of the included studies identified associations between the prevalence of MetS and RCRSP. Studies consistently identified independent cardiometabolic risk factors associated with RCRSP. All studies were level III evidence.

Summary and conclusion

The low-moderate quality evidence included in this review suggests an association between MetS and RCRSP. Most studies demonstrated moderate quality on appraisal. The direction of association and cardiometabolic factors influencing should be investigated by longitudinal and treatment studies. These preliminary conclusions and clinical utility should be treated with caution due to limitations of the evidence base.

Comparison of one-stage versus two-stage procedure for the management of patients with rotator cuff tear and concomitant shoulder stiffness

Background

To compare the clinical outcomes of one-stage and two-stage procedures for the management of patients with rotator cuff tear and concomitant shoulder stiffness.

Methods

From December 2013 to June 2016, we recruited 42 consecutive patients with rotator cuff tear and concomitant shoulder stiffness. Twenty-two patients underwent a one-stage procedure, including arthroscopic capsule release and concomitant rotator cuff repair, within 2 weeks of the diagnosis. For the remaining twenty patients, conservative treatment for the recovery of range of motion (ROM) was initially performed before arthroscopic rotator cuff repair. The ROM, visual analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score, and satisfaction rate were assessed preoperatively; 3, 6, 12, and 24 months after surgery; and at final follow-up.

Results

The mean follow-up period was 26.3 months (range, 24–33 months). No significant difference was noted in preoperative demographic data (age, sex, dominant/non-dominant, diabetes mellitus, thyroid disease, and duration of symptoms) between the two groups (P = 0.165, P = 0.580, P = 0.662, P = 0.716, P = 0.231, and P = 0.152, respectively). After treatment, all patients exhibited significant improvement in ROM and functional scores (P = 0.001 and P = 0.001, respectively). At 3 months postoperatively, the two-stage group exhibited significantly improved forward flexion and internal rotation compared with the one-stage group (P = 0.001 and P = 0.038, respectively). No significant difference in ROM was noted between the two groups at 6, 12, 24 months postoperatively and the final follow-up. In addition, no significant differences in VAS, ASES, Constant-Murley score and satisfaction rate were noted between the two groups at final follow-up (P = 0.319, P = 0.529, P = 0.711, and P = 0.085, respectively).

Conclusion

In the treatment of rotator cuff tear with concomitant stiffness, although the recovery of ROM took longer in patients who underwent the one-stage procedure, satisfactory results at final follow-up can be achieved using either the one-stage procedure or two-stage procedure.

Study design

Case-control study.

Effect of Resistance Exercise on Serum Osteoprotegerin Levels and Insulin Resistance in Middle-Aged Women with Metabolic Syndrome

Background

Osteoprotegerin (OPG) is a soluble glycoprotein that belongs to the tumor necrosis factor (TNF) receptor superfamily. OPG is mainly secreted by bone. The relationship between acute resistance training, serum OPG levels and metabolic syndrome, including insulin resistance, remains unclear. The purpose of this study was to determine the effect of resistance exercise on serum OPG levels and insulin resistance in middle-aged women with metabolic syndrome.

Material/Methods

Twenty-four middle-aged women were divided into those with metabolic syndrome (n=12) and a normal control group without metabolic syndrome or insulin resistance (n=12). Metabolic syndrome was diagnosed according to the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) criteria. The quantitative insulin-sensitivity check index (QUICKI) and the homeostatic model assessment (HOMA) index for assessing beta-cell function and insulin resistance were used. The intensity of the resistance exercise was 60–70% of the repetition maximum, for 40 minutes with 10–12 repetitions, performed three times per week. Venous blood samples were tested using standard laboratory procedures.

Results

Before exercise, the metabolic syndrome group showed a significant increase in waist circumference (P=0.030) and serum triglyceride (TG) (P=0.014), and lower high-density lipoprotein-cholesterol (HDL-C) (P=0.010) compared with the control group. After the eight-week resistance exercise program, waist circumference, and the QUICKI decreased and OPG levels were significantly increased in the metabolic syndrome group compared with the normal control group.

Conclusions

A resistance exercise program was effective in reducing factors associated with metabolic syndrome including insulin resistance and increases serum levels of OPG in middle-aged women.

Corticosteroid injection alone vs additional physiotherapy treatment in early stage frozen shoulders

AIM

To investigate the additional value of physiotherapy after a corticosteroid injection in stage one or two idiopathic frozen shoulders (FSs).

METHODS

A two center, randomized controlled trial was done. Patients with a painful early stage idiopathic FS were eligible for inclusion. After written consent, patients were randomly allocated into two groups. All patients received an ultrasound-guided intra-articular corticosteroid injection. One group underwent additional physiotherapy treatment (PT) and the other group did not (non-PT). The primary outcome measure was the Shoulder Pain and Disability Index (SPADI). Secondary outcomes were pain (numeric pain rating scale), range of motion (ROM), quality of life (RAND-36 score), and patient satisfaction. Follow-up was scheduled after 6, 12 and 26 wk.

RESULTS

Twenty-one patients were included, 11 patients in the non-PT and ten in the PT group, with a mean age of 52 years. Both treatment groups showed a significant improvement at 26 wk for SPADI score (non-PT: P = 0.05, PT: P = 0.03). At the 6 wk follow-up, median SPADI score was significant decreased in the PT group (14 IQR: 6-38) vs the non-PT group (63 IQR: 45-76) (P = 0.01). Pain decreased significantly in both groups but no differences were observed between both treatment groups at any time point, except for night pain at 6 wk in favor of the PT group (P = 0.02). Significant differences in all three ROM directions were observed after 6 wk in favor of the PT group (P ≤ 0.02 for all directions). A significantly greater improvement in abduction (P = 0.03) and external rotation (P = 0.04) was also present in favor of the PT group after 12 wk. RAND-36 scores showed no significant differences in health-related quality of life at all follow-up moments. At 26 wk, both groups did not differ significantly with respect to any of the outcome parameters. No complications were reported in both groups.

CONCLUSION

Additional physiotherapy after corticosteroid injection improves ROM and functional limitations in early-stage FSs up to the first three months.

Parkinson disease and musculoskeletal pain: an 8-year population-based cohort study

The aim of this study was to evaluate the incidence and clinical features of musculoskeletal pain (MSP) in patients with Parkinson disease (PD) compared with a control group without the disease. The retrospective cohort study used a subset of the Taiwan National Health Insurance Research Database (NHIRD) comprising information on 1 million beneficiaries randomly sampled from the entire population of Taiwan. A total of 490 patients aged 50 and above with newly diagnosed Parkinson disease were identified during a period from 2000 to 2005. Among them, 199 developed MSP after PD. The control group consisted of 1960 participants without PD over the study period randomly selected by matching PD cases according to the date of PD incidence, age, and sex. The study groups were then followed to the end of 2007. Musculoskeletal pain was the end point. The incidence rate ratios of MSP were higher in the PD group than in the control group, representing an adjusted hazard ratio of 1.31 (95% confidence interval 1.09 to 1.58). PD was associated with a significantly elevated risk of MSP in all sex and age stratifications, with the highest hazard ratio noted for middle-aged male patients with PD, followed by older male patients with PD. This study showed that the PD may significantly increase the risk of developing MSP. The risk of developing MSP seems to be greatest for middle-aged male patients with PD. Clinicians should be more alert for MSP in patients with PD, and early intervention should be considered.

Risk Factors for Shoulder Stiffness: Current Concepts

Shoulder stiffness is a condition of painful restriction of the glenohumeral range of motion. Numerous risk factors for primary and postoperative shoulder stiffness have been described. This article summarizes the known aspects of the pathophysiology of shoulder stiffness, with special attention to elements of molecular biology and genetics, which could influence the risk of developing shoulder stiffness. Furthermore, the role of hormonal and metabolic factors, medical disorders, drugs, and of other published risk factors for primary and postoperative shoulder stiffness is reviewed and discussed. Finally, aspects related to shoulder surgery and postoperative rehabilitation protocols, which could influence the development of postoperative stiffness are presented.