Association between fasting glucose levels and adhesive capsulitis in a normoglycemic population: a case-control study

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.

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

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

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.

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.

Associations of normal fasting glucose levels and of insulin resistance with degenerative rotator cuff tear : Normoglycemia and rotator cuff tear

BACKGROUND

The upper normoglycemic range has been proposed as a risk factor for degenerative rotator cuff tendon tear (RCT), and insulin resistance has been suggested as a risk factor for tendinopathy. However, no research has established their association with degenerative RCT in the general population. This study aimed to determine whether fasting glucose levels and insulin resistance are risk factors for degenerative RCT in the normoglycemic population and identify the risk range for fasting glucose.

METHODS

This study included 418 normoglycemic participants from a rural cohort. Participants completed questionnaires, physical exams, blood tests, and MRI evaluations of both shoulders. Insulin resistance was assessed using a triglyceride/high-density-lipoprotein (TG/HDL) ≥ 3.5. Logistic regression analysis was used to determine the association between fasting glucose level, TG/HDL ≥ 3.5, and other factors and degenerative RCT. The study calculated the areas under the receiver operating characteristic curve (AUC) to determine the more appropriate predicting value between the scale and categorical values of fasting glucose levels, and compared the AUCs using the DeLong method.

RESULTS

In the multivariable analyses, both scale and categorical values of fasting glucose levels, and TG/HDL ≥ 3.5 were significantly associated with degenerative RCT. Fasting glucose levels ≥ 90.5 mg/dL (OR: 3.87, 95% CI: 2.10-7.06) in scale value and 90-99 mg/dL (OR: 4.13, 95% CI: 2.87-8.12) in categorical value were significantly associated with degenerative RCT (P < .001). The AUC of the scale value of fasting glucose levels ≥ 90.5 mg/dL was 0.68. The AUC of the categorical value of fasting glucose levels of 90-99 mg/dL was 0.70. Because of the significantly larger AUC of the categorical value of fasting glucose levels of 90-99 mg/dL, those fasting glucose levels were determined to be independently associated with degenerative RCT (P < .001).

CONCLUSIONS

High fasting glucose levels within the normal range may link to increase insulin resistance and risk of degenerative RCT. Normoglycemic levels of 90-99 mg/dL and insulin resistance may be risk factors for degenerative RCT.

LEVEL OF EVIDENCE

Level III, prognostic study.

Suprascapular Nerve Block (SSNB) improves the outcome in exercise based management of Primary Adhesive Capsulitis (PAC): A prospective randomized comparative study

Background and Aims

Increased pain and associated stiffness hinders the advantages of exercise and process of recovery in primary adhesive capsulitis. We hypothesized that suprascapular nerve block may positively affect the outcome due to its role in pain relief of acute or chronic shoulder pain. We compared the effect of suprascapular nerve block and exercise with only exercise on the recovery of primary adhesive capsulitis.

Material and Methods

A total of 96 patients of both sexes presenting with primary adhesive capsulitis were divided by computer randomization in two equal groups (n = 48). Group A received exercise only and Group B received suprascapular nerve block followed by exercise. Oral paracetamol was given for analgesia as desired. Patients were followed up at 4, 8, 16, and 24 weeks. Pain was assessed by visual analog scale; functional outcome by Shoulder Pain and Disability Index and range of movement by goniometer.

Results

The pain scores and Shoulder Pain and Disability Index scores were significantly lower at all observation points of 4, 8,16, and 24 weeks in Group B than Group A (P < 0.05). The range of movement in all the ranges of forward flexion, extension, internal and external rotation, and abduction at all observation points was significantly higher in Group-B (P < 0.05) compared to Group A. The consumption of analgesics was significantly more in Group A than Group B at 4 and 8 weeks (P = 0.020 and P = 0.044) but comparable at 12 and 24 weeks (P = 0.145 and P = 0.237 respectively).

Conclusion

Combining SSNB with exercise is more effective in treatment of primary adhesive capsulitis than exercise alone and reduces the use of analgesics. SSNB it is effective and safe to use in primary adhesive capsulitis.

Trends in Practice Among Shoulder Specialists in the Management of Frozen Shoulder: A Consensus Survey

Background:

The management of frozen shoulder (FS) differs depending on experience level and variation between scientific guidelines and actual practice.

Purpose:

To determine the current trends and practices in the management of FS among shoulder specialists and compare them with senior shoulder specialists.

Study Design:

Consensus statement.

Methods:

A team of 15 senior shoulder specialists (faculty group) prepared a questionnaire comprising 26 questions regarding the definition, terminology, clinical signs, investigations, management, and prognosis of FS. The questionnaire was mailed to all the registered shoulder specialists of Shoulder and Elbow Society, India (SESI) (specialist group; n = 230), as well as to the faculty group (n = 15). The responses of the 2 groups were compared, and levels of consensus were determined: strong (>75%), broad (60%-74.9%), inconclusive (40%-59.9%), or disagreement (<40%).

Result:

Overall, 142 of the 230 participants in the specialist group and all 15 participants in the faculty group responded to the survey. Both groups strongly agreed that plain radiographs are required to rule out a secondary cause of FS, routine magnetic resonance imaging is not indicated to confirm FS, nonsteroidal anti-inflammatory drugs should be administered at bedtime, steroid injection (triamcinolone or methylprednisolone) is the next best option if analgesics fail to provide pain relief, passive physical therapy should be avoided in the freezing phase, <10% of patients would require any surgical intervention, and patients with diabetes and thyroid dysfunction tend to fare poorly. There was broad agreement that routine thyroid dysfunction screening is unnecessary for women, a single 40-mg steroid injection via intra-articular route is preferred, and arthroscopic capsular release (ACR) results in a better outcome than manipulation under anesthesia (MUA). Agreement was inconclusive regarding the use of combined random blood sugar (RBS) and glycosylated hemoglobin versus lone RBS to screen for diabetes in patients with FS, preference of ACR versus MUA to treat resistant FS, and the timing of surgical intervention. There was disagreement over the most appropriate term for FS, the preferred physical therapy modality for pain relief, the most important movement restriction for early diagnosis of FS, and complications seen after MUA.

Conclusion:

This survey summarized the trend in prevalent practices regarding FS among the shoulder specialists and senior shoulder surgeons of SESI.

Involvement of inflammatory lipoproteinemia with idiopathic adhesive capsulitis accompanying subclinical hypothyroidism

BACKGROUND

Thyroid functional abnormalities are considered risk factors for idiopathic adhesive capsulitis (IAC) though that relationship remains uncertain. Although dyslipidemias are associated with IAC, no readily accessible study has reported associations between dyslipidemias and IAC patients with subclinical hypothyroidism. The purposes of this study were to investigate whether subclinical hypothyroidism is an independently associated factor for IAC and to determine the differences in prevalence of dyslipidemias between two groups of persons with subclinical hypothyroidism: one composed of IAC patients and the other of individuals without IAC.

METHODS

This case-control study included a case group of 412 IAC patients without intrinsic shoulder lesions, extrinsic causes, or medication for thyroid dysfunction. The control group comprised 1236 age- and sex-matched persons seeking general checkups at the authors' health promotion center during the same period as the case group. Control subjects had normal shoulder function and no previously diagnosed adhesive capsulitis, no medication for thyroid dysfunction, and no history of trauma or of shoulder surgery. The studied variables were age, gender, obesity, diabetes, dyslipidemias, subclinical hypothyroidism, hypothyroidism, and hyperthyroidism. A conditional logistic regression analysis evaluated the matched sets of subjects to determine odds ratios and 95% confidence intervals for the studied variables. The differences in the prevalence of dyslipidemias between IAC patients with subclinical hypothyroidism and individuals with subclinical hypothyroidism but without IAC were determined with generalized estimating equations, using covariates of age, sex, and diabetes. The P values were set at < 0.05.

RESULTS

Subclinical hypothyroidism (odds ratio, 2.10; 95% confidence interval, 1.36-3.15; P = .001) was significantly associated with IAC. Patients with IAC and subclinical hypothyroidism had a significantly higher prevalence of hyper-low-density lipoproteinemia, an inflammatory lipoproteinemia, than individuals with subclinical hypothyroidism but without IAC (P = .002).

CONCLUSIONS

Subclinical hypothyroidism is significantly associated with IAC. Hyper-low-density lipoproteinemia, an inflammatory lipoproteinemia, is involved in IAC accompanied by subclinical hypothyroidism.

Radial shock-wave therapy for frozen shoulder patients with type 2 diabetes mellitus: a pilot trial comparing two different energy levels

BACKGROUND

Extracorporeal shock-wave therapy (ESWT) is highly recommended for the management of orthopedic shoulder pathologies. Yet, the clinical relevance of the dose difference effect of radial ESWT approaches in the management of frozen shoulder patients with type 2 diabetes mellitus remains uncertain.

AIM

The aim was to examine the short-term effects of medium-and high-energy levels of radial ESWT (rESWT) in the treatment of frozen shoulder patients with type 2 diabetes mellitus.

DESIGN

Prospective clinical pilot study.

SETTING

This study was conducted in an outpatient clinic.

POPULATION

Thirty-nine patients who had frozen shoulder untreated for at least 3 months, diagnosed with type 2 diabetes mellitus for ≥3 years were included.

METHODS

The patients were randomly allocated to receive either high-energy rESWT (hrESWT), or medium-energy rESWT (mrESWT) or placebo at 8 Hz twice a week for six weeks. The primary outcome measure was pain, evaluated by the Visual Analog Scale (VAS) Score. Secondary outcome measures were function evaluated by the Shoulder Pain and Disability Index (SPADI) Score, and shoulder active range of motion (AROM). The mechanical properties of the deltoid and trapezius muscles were assessed using the MyotonPRO (Myoton AS, Tallinn, Estonia).

RESULTS

The mrESWT resulted in statistically significant reductions in night pain at 6 weeks (η<inf>p</inf>²=0.27, P=0.003). Significantly improved function (SPADI scores: -35.42±21.29 vs.-29.59±22.60; η<inf>p</inf>²=0.39, P˂0.001) was found in both hrESWT and mrESWT group by 6 weeks. Significantly higher mean shoulder AROM values were recorded for external rotation (η<inf>p</inf>²=0.53, P<0.001), and internal rotation (η<inf>p</inf>²=0.21, P=0.020), in the hrESWT group at the 6^th week. A significantly improved resting tone (η<inf>p</inf>²=0.58) and stiffness of deltoid muscle (η<inf>p</inf>²=0.62) were found in the mrESWT group (P<0.001). The trapezius muscle resting tone reduced with hrESWT (η<inf>p</inf>²=0.17, P=0.033).

CONCLUSIONS

Regardless of the energy levels, rESWT appears to be an effective therapeutic intervention for frozen shoulder patients with type 2 diabetes mellitus in the short-term results.

CLINICAL REHABILITATION IMPACT

Our results suggest that this rESWT can be a useful strategy for the rehabilitation of frozen shoulder patients with type 2 diabetes mellitus. This is the first study on dose difference effectiveness in terms of the clinical significance of rESWT which is key to transfer research evidence into practice.

Causes of Shoulder Dysfunction in Diabetic Patients: A Review of Literature

Objective: Understanding the underlying mechanisms behind shoulder dysfunctions in patients with diabetes mellitus. Study Design: Systematic qualitative literature review. Participants: Patients with shoulder dysfunctions and diagnosed with impaired glucose tolerance or diabetes mellitus. Intervention: Published scientific literature containing evidence about the mechanisms of shoulder dysfunctions in the diabetic population. Articles were selected based on criteria containing diabetic population, shoulder dysfunction, methodological quality ≥ 6/9 and >20 subjects. Main Outcome measures: range of motion; questionnaires (QoL, UCLA-m, SPADI, DASH); blood glucose, blood HbA1C; calculated capsular stiffness (Kcap); calcification shoulder joint; shoulder dysfunction in patients with glucose metabolism disorders and diabetes mellitus. Results: We found 17 published articles with level 2 and 3 evidence. Multiple factors such as age, duration of diabetes mellitus (DM), glycated hemoglobin (HbA1c), advanced glycation end products (AGE), vascular endothelial growth factor (VEGF), interleukin-1ß (IL-1ß) were shown to be associated with tendon changes and increased capsular stiffness (Kcap) conceivably leading to limited range of motion (ROM) or frozen shoulder. Decreased ROM and frozen shoulder have a significantly higher prevalence in DM than in non-DM. Conclusions: Based on the current literature we confirm a high prevalence of shoulder dysfunctions in patients with diabetes mellitus. The cause of the shoulder complications is unknown, and more research is mandatory to shed more light on the complex interplay between the multifactorial causes of shoulder dysfunction in diabetes mellitus.

Adhesive capsulitis: A review for clinicians

ABSTRACT

Adhesive capsulitis, a common primary care and orthopedic diagnosis often referred to as frozen shoulder, is a painful inflammatory process that leads to a mechanical block in active and passive range of shoulder motion. Risk factors include diabetes and thyroid dysfunction. Diagnosis is made based on physical examination, but can be augmented by diagnostic imaging. Nonsurgical management is the mainstay of treatment because the disease is self-limiting. However, some patients may need surgical intervention.

Keratin-inorganic hybrid nanoflowers decorated with Fe3O4 nanoparticles as enzyme mimics for colorimetric detection of glucose

Fe₃O₄ magnetic nanoparticles (MNPs) are highly active enzyme-like catalysts. However, low stability is still a big challenge for Fe₃O₄-based enzyme mimics because the Fe₃O₄ MNPs can be easily dissolved when exposed to acidic conditions. Inspired by the numerous catalytic sites of a flower-like structure and the biological functions of amino acids in structural proteins, herein, by employing keratin as a protein component, stable Fe₃O₄-based MNP embedded keratin-Cu₃(PO₄)₂ nanoflowers were constructed, from which hierarchical nanostructures with a three-dimensional petal-like morphology were selected for subsequent studies owing to their excellent enzymic catalytic activity. The keratin-nanoflower@Fe₃O₄ exhibited significantly enhanced catalytic activity compared with that of keratin-Cu₃(PO₄)₂ nanoflowers and individual Fe₃O₄ MNPs. Remarkably, keratin-nanoflower@Fe₃O₄ exhibited superior long-term stability to Fe₃O₄ MNPs under more acidic conditions and favorable reusability. This method has been successfully exploited for the colorimetric determination of glucose in human serum with satisfactory sensitivity and specificity, offering a novel approach for glucose detection.

Clinical Guidelines in the Management of Frozen Shoulder: An Update!

Among all the prevalent painful conditions of the shoulder, frozen shoulder remains one of the most debated and ill-understood conditions. It is a condition often associated with diabetes and thyroid dysfunction, and which should always be investigated in patients with a primary stiff shoulder. Though the duration of 'traditional clinicopathological staging' of frozen shoulder is not constant and varies with the intervention(s), the classification certainly helps the clinician in planning the treatment of frozen shoulder at various stages. Most patients respond very well to combination of conservative treatment resulting in gradual resolution of symptoms in 12-18 months. However, the most effective treatment in isolation is uncertain. Currently, resistant cases that do not respond to conservative treatment for 6-9 months could be offered surgical treatment as either arthroscopic capsular release or manipulation under anaesthesia. Though both invasive options are not clinically superior to another, but manipulation could result in unwarranted complications like fractures of humerus or rotator cuff tear.

The Serum from Patients with Secondary Frozen Shoulder Following Rotator Cuff Repair Induces Shoulder Capsule Fibrosis and Promotes Macrophage Polarization and Fibroblast Activation

PURPOSE

Disorders with systematic inflammation were prognostic for secondary frozen shoulder (sFS) following rotator cuff repair (RCR); however, how systematic inflammation affects sFS remains unclear. The aim of this study was to observe the effect of pre-operative serum from patients with sFS and the serum from those without on shoulder capsule in mice, and on macrophages and fibroblasts in vitro.

METHODS

Serum samples of a consecutive cohort of patients for RCR were collected pre-operatively. Three months after RCR, patients who developed sFS (Group S) were identified. Serum samples from gender- and age-matched controls without sFS (group NS) were also picked out. Firstly, the effect of serum on shoulder capsule fibrosis was observed histologically and biomechanically in a mouse model of RCR. Secondly, the roles of the serum on macrophage polarization and fibroblast activation were investigated, and the potentially involved signaling pathways were identified. Finally, inflammation and fibrosis-related cytokines in serum were quantified.

RESULTS

In our cohort, all patients had free pre-operative shoulder range of motion. Seven patients developed sFS at 3 months after surgery. Seven matched patients without sFS were selected as control. The inter-group difference of basic characteristics was not significant. Compared to the serum of group NS, the serum of group S significantly induced hypercellularity, capsular thickening, and range of motion deficiency in mice shoulders after RCR. Compared to the serum of group NS, samples of group S significantly promoted M2 polarization of THP-1 human macrophages and the activation of human capsule-derived fibroblasts. Meanwhile, Smad3 and p-Smad3 in macrophages and fibroblasts were significantly up-regulated. On the other hand, levels of inflammation and fibrosis-related cytokines were not significantly different between serum in group S and group NS.

CONCLUSION

Although all patients in this cohort had free range of motion pre-operatively, the pre-operative serum from patients with sFS at 3 months after RCR could act as a trigger of shoulder capsule fibrosis post-operatively. This effect may be related to its promotion on macrophage polarization to M2 phenotype and fibroblast activation.