Shoulder manifestations of diabetes mellitus

Involvement of TRPM7 Channel on the Induction of Diabetic Neuropathic Pain in Mice: Protective Role of Selenium and Curcumin

Excessive levels of the mitochondrial reactive oxygen radical (mitSOX) and Ca²⁺ influx were found to cause neuropathic pain in patients with diabetes mellitus (DM). Naltriben (NLT) and mitSOX activate the transient receptor (TRP) melastatin 7 (TRPM7) channel, but antioxidants and carvacrol inhibit it. Selenium (Se) and curcumin (CRC) have been thoroughly studied for their modulator effects on streptozotocin (STZ)-induced neuropathic pain, apoptosis, and oxidative stress through the blockage of TRP channels in dorsal root ganglion (DRG) neurons. It has not yet been fully understood how Se and CRC protect against STZ-induced neuropathic pain by modulating TRPM7. Here, we assessed how Se and CRC affected the Ca²⁺ influx, mitSOX-mediated oxidative damage, and apoptosis in the DRGs of mice through modifying TRPM7 activity. Seven groups (control, Se, CRC, STZ, STZ + Se, STZ + CRC, and STZ + Se + CRC) were induced from the 56 male mice. We observed that the STZ-induced stimulation of TRPM7 increased mechanical neuropathic pain (von Frey), thermal neuropathic pain (hot plate), cytosolic Ca²⁺, TRPM7 current density, TRPM7 expression, lipid peroxidation, mitSOX, cytosolic ROS, apoptosis, caspase-3, caspase-8, and caspase-9 concentrations, whereas Se and CRC therapies diminished the alterations. The STZ-mediated decreases of DRG viability, brain glutathione, glutathione peroxidase, vitamin A, and vitamin E concentrations were also upregulated in the treatment groups by the therapies. These findings collectively imply that an imbalance of neuropathic pain, oxidative neurotoxicity, and apoptosis in the mice is caused by the STZ-mediated activation of TRPM7. However, the downregulation of TRPM7 activity caused by the injections of Se and CRC reduced the neurotoxicity and apoptosis.

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.

The sonographic quantitative assessment of the deltoid muscle to detect type 2 diabetes mellitus: a potential noninvasive and sensitive screening method?

BACKGROUND

In our previous published study, we demonstrated that a qualitatively assessed elevation in deltoid muscle echogenicity on ultrasound was both sensitive for and a strong predictor of a type 2 diabetes (T2DM) diagnosis. This study aims to evaluate if a sonographic quantitative assessment of the deltoid muscle can be used to detect T2DM.

METHODS

Deltoid muscle ultrasound images from 124 patients were stored: 31 obese T2DM, 31 non-obese T2DM, 31 obese non-T2DM and 31 non-obese non-T2DM. Images were independently reviewed by 3 musculoskeletal radiologists, blinded to the patient's category. Each measured the grayscale pixel intensity of the deltoid muscle and humeral cortex to calculate a muscle/bone ratio for each patient. Following a 3-week delay, the 3 radiologists independently repeated measurements on a randomly selected 40 subjects. Ratios, age, gender, race, body mass index, insulin usage and hemoglobin A_1c were analyzed. The difference among the 4 groups was compared using analysis of variance or chi-square tests. Both univariate and multivariate linear mixed models were performed. Multivariate mixed-effects regression models were used, adjusting for demographic and clinical variables. Post hoc comparisons were done with Bonferroni adjustments to identify any differences between groups. The sample size achieved 90% power. Sensitivity and specificity were calculated based on set threshold ratios. Both intra- and inter-radiologist variability or agreement were assessed.

RESULTS

A statistically significant difference in muscle/bone ratios between the groups was identified with the average ratios as follows: obese T2DM, 0.54 (P < 0.001); non-obese T2DM, 0.48 (P < 0.001); obese non-T2DM, 0.42 (P = 0.03); and non-obese non-T2DM, 0.35. There was excellent inter-observer agreement (intraclass correlation coefficient 0.87) and excellent intra-observer agreements (intraclass correlation coefficient 0.92, 0.95 and 0.94). Using threshold ratios, the sensitivity for detecting T2DM was 80% (95% CI 67% to 88%) with a specificity of 63% (95% CI 50% to 75%).

CONCLUSIONS

The sonographic quantitative assessment of the deltoid muscle by ultrasound is sensitive and accurate for the detection of T2DM. Following further studies, this process could translate into a dedicated, simple and noninvasive screening method to detect T2DM with the prospects of identifying even a fraction of the undiagnosed persons worldwide. This could prove especially beneficial in screening of underserved and underrepresented communities.

Noopept Attenuates Diabetes-Mediated Neuropathic Pain and Oxidative Hippocampal Neurotoxicity via Inhibition of TRPV1 Channel in Rats

Neuropathic pain and oxidative neurotoxicity are two adverse main actions of diabetes mellitus (DM). The expression levels of calcium ion (Ca²⁺) permeable TRPV1 channels are high in the dorsal root ganglion (DRGs) and hippocampus (HIPPO). TRPV1 is activated by capsaicin and reactive free oxygen radicals (fROS) to mediate peripheral neuropathy and neurotoxicity. Noopept (NP) acted several protective antioxidant actions against oxidative neurotoxicity. As DM is known to increase the levels of fROS, the protective roles of antioxidant NP were evaluated on the DM-mediated neurotoxicity and neuropathic pain via the modulation of TRPV1 in rats. Thirty-six rats were equally divided into control, NP, DM (streptozotocin, STZ), and STZ + NP groups. A decrease on the STZ-mediated increase of neuropathic pain (via the analyses of Von Frey and hot plate) and blood glucose level was observed by the treatment of NP. A protective role of NP via downregulation of TRPV1 activity on the STZ-induced increase of apoptosis, mitochondrial fROS, lipid peroxidation, caspase -3 (CASP-3), caspase -9 (CASP-9), TRPV1 current density, glutathione (GSH), cytosolic free Zn²⁺, and Ca²⁺ concentrations in the DRGs and HIPPO was also observed. The STZ-mediated decrease of glutathione peroxidase, GSH, vitamin E, and β-carotene concentrations in the brain cortex, erythrocyte, liver, kidney, and plasma was also attenuated by the treatment of NP. The STZ-mediated increase of TRPV1, CASP-3, and CASP-9 expressions was decreased in the DRGs and HIPPO by the treatment of NP. In conclusion, the treatment of NP induced protective effects against STZ-induced adverse peripheral pain and HIPPO oxidative neurotoxicity. These effects might attribute to the potent antioxidant property of NP.

The Prevalence of Shoulder Pain and Its Functional Limitations Among Patients With Uncontrolled Diabetes

Objectives

To investigate the prevalence of shoulder pain and its functional limitations among patients with uncontrolled diabetes mellitus (DM).

Methods

This is a cross-sectional study that was conducted over a period of four months from October 2019 to January 2020 and included all patients with uncontrolled DM (HbA1c > 9) who are visiting the diabetes clinic at Security Forces Hospital during the study period. Telephone interviews were held by a physician from the Family Medicine Department using a previously validated questionnaire, that is, the American Shoulder and Elbow Surgeons Evaluation Form.

Results

A total of 285 patients were included in the study; 156 (54.7%) were females and 129 (45.3%) were males. Most (51.1%) of the patients aged 45-64 years. The majority of the patients 58.9% had type II DM and 41.1% of them had type I DM. The mean HbA1c level was 10.56. Of the patients are having shoulder pain (109; 38.2%), 42.5% were between 45 and 64 years of age and 44.1% were between 65 and 96 of years. While 176 (61.8%) of the participants had no pain at all, 70.5% males and 54.5% females did not have shoulder pain (p<0.001). The mean shoulder pain intensity for all patients was 5.81(SD=3.21), ranging from 4.71 (SD=3.15) to 6.13 (SD=3.29), according to different age groups, and showed a significant correlation (p<0.05).

Conclusions

Increasing prevalence of shoulder dysfunction is making physicians alert regarding early diagnosis and management of the disease. Thus, it should be mandatory to include screening, prevention, and rehabilitation strategies for shoulder dysfunction in diabetic care programs to improve the daily lifestyle of the patients.

The Hyperechoic Appearance of the Deltoid Muscle on Shoulder Ultrasound Imaging as a Predictor of Diabetes and Prediabetes

OBJECTIVES

To evaluate whether the ultrasound appearance of the deltoid muscle in diabetic patients differs from that in obese nondiabetic patients.

METHODS

Ultrasound images of the deltoid muscle from 137 type 2 diabetic patients (including 13 prediabetic patients) and 49 obese nondiabetic patients were blindly reviewed by 2 musculoskeletal radiologists, and by a third when arbitration was needed, to determine whether the appearance was "normal," "suspected diabetes," or "definite diabetes." Age, sex, race, body mass index (BMI), insulin use, and hemoglobin A_1c were analyzed. This retrospective study included patients presenting between October 2005 and November 2017. Statistical analyses included a 2-sided sample t test or Wilcoxon rank sum test and a χ² or Fisher exact test. Statistical significance was defined as P < .05.

RESULTS

The type 2 diabetic patients included 98 women and 39 men aged 29 to 92 years, and the nondiabetic patients included 19 women and 30 men aged 18 to 75 years. A consensus diagnosis of definite diabetes by the musculoskeletal radiologists based on a hyperechoic deltoid was a powerful predictor of diabetes, with a positive predictive value of 89%. A hyperechoic deltoid was also a powerful predictor of prediabetes. Of the 13 prediabetic patients, all had the same hyperechoic appearance of the diabetic deltoid, regardless of BMI. Although obese diabetic patients more often had a diagnosis of definite diabetes, the BMI alone could not explain the increased echogenicity, as obese nondiabetic patients' deltoid muscles did not appear as hyperechoic and were correctly categorized as not having definite diabetes with 82% specificity.

CONCLUSIONS

The characteristic hyperechoic deltoid appearance is a strong predictor of both diabetes and prediabetes and differs from that of obese nondiabetic patients.

The comparison of frequency of the upper limb musculoskeletal disorders among patients with diabetes type II with normal cases

Background and aim

Musculoskeletal disease, that is recognized in diabetes and diabetes mellitus (DM) has shown a higher prevalence of chronic musculoskeletal complications. This study aimed at assessing the frequency of upper limb musculoskeletal disorders among patients with diabetes type II with normal cases in Mashhad, Iran.

Methods

A cross-section of 100 patients with upper limb musculoskeletal disorders were enrolled in this study. The patients were examined by a unique physician considering carpal tunnel syndrome disorder, trigger finger, adhesive capsulitis, and Dupuytren's contracture at Ghaem hospital, Mashhad, Iran in 2015. All collected data were recorded by using SPSS version 21 and were analyzed through independent-samples t-test for comparing changes, and Chi-square.

Results

In this study, the mean age was 51.7±8.7 years old. Gender frequency was 114 (57%) male, and 86 (43%) female. There was no significant difference between groups in cases of gender frequency and mean of age (p>0.05). In evaluation of association between the two groups, there was significant difference for adhesive capsulitis, (p=0.04). Chi-square test showed significant association for age and adhesive capsulitis between the two groups, (p=0.040); but no other diabetes-related disorders, (p<0.05).

Conclusion

The results of this study showed that in patients with diabetes mellitus and musculoskeletal complications such as upper limb musculoskeletal abnormalities, it will lead to an increase in skeletal muscle effects in DM patients. It is recommended that musculoskeletal examination is done periodically in DM patients for identification of these disorders and necessary actions are carried out for prevention of the disorders as soon as possible.

Musculoskeletal manifestations in diabetic versus prediabetic patients

AIM

This study was carried out to evaluate the prevalence of musculoskeletal manifestations in a sample of patients with diabetes mellitus (DM) and those with prediabetes and compare the findings between the two groups.

METHODS

One hundred and eighty-eight patients with DM and 125 prediabetic subjects were randomly enrolled in this cross-sectional study. Demographic data and past history were recorded. Musculoskeletal physical examinations were done by a single rheumatologist. Regression analyses were employed to assess the crude and adjusted effects of determinants on DM musculoskeletal manifestations (DMMMs).

RESULTS

Female/male ratio was not significantly different between diabetic and prediabetic patients (4.4 vs. 4.7, respectively, P = 0.9). However, diabetic patients were significantly older than the prediabetic ones (56.6 vs. 52 years, respectively, P = 0.0001); 83.5% of diabetic patients and 52.8% of prediabetic ones had at least one musculoskeletal manifestation (P = 0.0001). The prevalence of knee osteoarthritis and shoulder involvement were almost two times more common (P = 0.0001 and P = 0.015) in diabetic patients than in prediabetic ones (73.4% vs. 38% and 21.2% vs. 9.5%, respectively). Prevalence of carpal tunnel syndrome (CTS) was 48% and 36.5% in patients with diabetes and prediabetes, respectively (P = 0.053). Multivariate backward regression analysis showed age, sex, BMI (body mass index) and DM as the significant determinants in development of musculoskeletal manifestations in all subjects. Age and BMI were the only significant factors associated with musculoskeletal manifestations in both diabetic and prediabetic patients.

CONCLUSION

Diabetic and prediabetic patients may show high prevalence of musculoskeletal manifestations. In non-diabetic patients diagnosed with CTS, prediabetes might be ruled out.

Modified suture-bridge technique to prevent a marginal dog-ear deformity improves structural integrity after rotator cuff repair

BACKGROUND

The arthroscopic suture-bridge technique has proved to provide biomechanically firm fixation of the torn rotator cuff to the tuberosity by increasing the footprint contact area and pressure. However, a marginal dog-ear deformity is encountered not infrequently when this technique is used, impeding full restoration of the torn cuff.

PURPOSE

To evaluate the structural and functional outcomes of the use of a modified suture-bridge technique to prevent a marginal dog-ear deformity compared with a conventional suture-bridge method in rotator cuff repair.

STUDY DESIGN

Cohort study; Level of evidence 2.

METHODS

A consecutive series of 71 patients aged 50 to 65 years who underwent arthroscopic rotator cuff repair for full-thickness medium-sized to massive tears was evaluated. Patients were divided into 2 groups according to repair technique: a conventional suture-bridge technique (34 patients; group A) versus a modified suture-bridge technique to prevent a marginal dog-ear deformity (37 patients; group B). Radiographic evaluations included postoperative cuff integrity using MRI. Functional evaluations included pre- and postoperative range of motion (ROM), pain visual analog scale (VAS), the University of California, Los Angeles (UCLA) shoulder rating scale, the Constant score, and the American Shoulder and Elbow Surgeons (ASES) score. All patients were followed up clinically at a minimum of 1 year.

RESULT

When the 2 surgical techniques were compared, postoperative structural integrity by Sugaya classification showed the distribution of types I:II:III:IV:V to be 4:20:2:4:4 in group A and 20:12:4:0:1 in group B. More subjects in group B had a favorable Sugaya type compared with group A (P < .001). The postoperative healed:retear rate was 26:8 in group A and 36:1 in group B, with a significantly lower retear rate in group B (P = .011). However, there were no significant differences in ROM and all functional outcome scores between the 2 groups postoperatively. When surgical techniques were compared across healed (n = 62) and retear (n = 9) groups, significantly fewer modified suture-bridge technique repairs were found in the retear group (P = .03). There were significant differences between healed and retear groups in functional outcome scores, with worse results in the retear group.

CONCLUSION

A modified suture-bridge technique to prevent a marginal dog-ear deformity provided better structural outcomes than a conventional suture-bridge technique for medium-sized to massive rotator cuff tears. This technique may ultimately provide better functional outcomes by decreasing the retear rate.

Effect of capsular release in the treatment of shoulder stiffness concomitant with rotator cuff repair: diabetes as a predisposing factor associated with treatment outcome

BACKGROUND

In spite of the high prevalence of shoulder stiffness during rotator cuff repair, optimal management remains unclear.

PURPOSE

To identify the effect of capsular release during rotator cuff repair on the outcomes of patients with both shoulder stiffness and a rotator cuff tear, based on subgroup analyses.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Forty-nine consecutive patients (mean age, 61.5 ± 8.3 years) were enrolled who underwent arthroscopic repair of a small- to large-sized full-thickness rotator cuff tear and manipulation for concomitant shoulder stiffness (passive forward flexion ≤120°, external rotation at the side ≤45°). The first 21 consecutive patients underwent manipulation alone to treat stiffness; the second 28 consecutive patients underwent capsular release with manipulation. Among the 49 patients, 25 showed severe stiffness (forward flexion ≤100°, external rotation at the side ≤30°; 11 in the first series and 14 in the second series), and 15 had diabetes mellitus (30.6%; 6 in the first series and 9 in the second series). Shoulder range of motion was measured 6 weeks, 3 months, 6 months, and 1 year postoperatively and at final follow-up visit. Simultaneously, functional outcome was evaluated by visual analog scale for pain, American Shoulder and Elbow Surgeons score, Constant score, and muscle strength ratio (involved/uninvolved), and cuff integrity was assessed ultrasonographically at least 1 year postoperatively.

RESULTS

All range of motion measurements, functional scores, and muscle strength ratios significantly improved postoperatively regardless of the treatment method of stiffness. No outcome measure differed significantly between patients who did and did not undergo capsular release, regardless of the severity of stiffness, except for a temporary improvement in external rotation at side 3 months postoperatively in favor of those who underwent capsular release in cases with severe stiffness. Among patients with diabetes mellitus however, those who underwent capsular release showed greater improvement in forward flexion after 3 months and 1 year and in external rotation at the side for all time points (all P < .05), except for 6 weeks postoperatively; these patients also had a significantly higher final American Shoulder and Elbow Surgeons score (P = .03). Of 21 patients who underwent manipulation alone and of 28 who underwent capsular release and manipulation, 2 and 1 developed retears, respectively.

CONCLUSION

Both manipulation and capsular release with manipulation significantly improved range of motion and produced satisfactory functional outcomes. The outcomes did not differ between treatment methods for stiffness regardless of the severity of stiffness. In patients with diabetes mellitus however, capsular release at the time of rotator cuff repair seems to be beneficial, especially for external rotation and final postoperative function.

Synergistic interaction between metformin and sulfonylureas on diclofenac-induced antinociception measured using the formalin test in rats

BACKGROUND

There is evidence that biguanides and sulfonylureas block diclofenac-induced antinociception (DIA) in rat models. However, little is known about the interaction between these hypoglycemics with respect to DIA.

OBJECTIVE

To determine whether metformin-sulfonylurea combinations affect DIA during the formalin test.

METHODS

Rats received the appropriate vehicle or diclofenac before 1% formaldehyde was injected into the paw. Rats were also pretreated with vehicle, glibenclamide, glipizide, metformin or glibenclamide⁄metformin and glipizide⁄metformin combinations before the diclofenac and formaldehyde injections, and the effect on antinociception was assessed. Isobolograms of the combinations were constructed to test for a synergistic interaction.

RESULTS

Systemic injection of diclofenac resulted in antinociception during the second phase of the test. Systemic pretreatment with the combinations of glibenclamide (0.56 mg⁄kg to 10 mg⁄kg)⁄metformin (10 mg⁄kg to 180 mg⁄kg) and glipizide (0.56 mg⁄kg to10 mg⁄kg)⁄metformin (10 mg⁄kg to 180 mg⁄kg) blocked DIA. The derived theoretical effective doses for 50% of subjects (ED50) for the glibenclamide⁄metformin and glipizide⁄metformin combinations were 32.52 mg⁄kg and 32.42 mg⁄kg, respectively, and were significantly higher than the actual observed experimental ED50 values (7.57 mg⁄kg and 8.43 mg⁄kg, respectively).

CONCLUSION

Pretreatment with glibenclamide, glipizide or metformin blocked DIA in a dose-dependent manner, and combining either sulfonylurea with metformin produced even greater effects. The observed ED50s for the combinations were approximately fourfold lower than the calculated additive effects. These data indicate that sulfonylureas interact to produce antagonism of DIA. Combination therapy is a common second-line treatment for patients with diabetes and metabolic syndrome, a group that experiences pain from multiple sources. The results suggest that at least some anti-inflammatory agents may not be effective in this group.

Management of limited joint mobility in diabetic patients

Several rheumatologic manifestations are more pronounced in subjects with diabetes, ie, frozen shoulder, rotator cuff tears, Dupuytren's contracture, trigger finger, cheiroarthropathy in the upper limb, and Achilles tendinopathy and plantar fasciitis in the lower limb. These conditions can limit the range of motion of the affected joint, thereby impairing function and ability to perform activities of daily living. This review provides a short description of diabetes-related joint diseases, the specific pathogenetic mechanisms involved, and the role of inflammation, overuse, and genetics, each of which activates a complex sequence of biochemical alterations. Diabetes is a causative factor in tendon diseases and amplifies the damage induced by other agents as well. According to an accepted hypothesis, damaged joint tissue in diabetes is caused by an excess of advanced glycation end products, which forms covalent cross-links within collagen fibers and alters their structure and function. Moreover, they interact with a variety of cell surface receptors, activating a number of effects, including pro-oxidant and proinflammatory events. Adiposity and advanced age, commonly associated with type 2 diabetes mellitus, are further pathogenetic factors. Prevention and strict control of this metabolic disorder is essential, because it has been demonstrated that limited joint motion is related to duration of the disease and hyperglycemia. Several treatments are used in clinical practice, but their mechanisms of action are not completely understood, and their efficacy is also debated.