Effect of Metabolic Syndrome on the Functional Outcome of Corticosteroid Injection for Lateral Epicondylitis: Retrospective Matched Case-Control Study

Effects of hyaluronic acid injections on pain and functioning in patients affected by tendinopathies: A narrative review

BACKGROUND

Tendinopathies are overuse tendon injuries showing load-dependant pain, stiffness, weakness of movement in the affected area, and impairment in the movements. The scientific interest on the role of Hyaluronic Acid (HA) for the management of tendinopathies has been increased due to its anti-inflammatory and lubricative properties.

OBJECTIVE

To collect evidence regarding the effectiveness and safety of HA injections in reducing pain in patients affected by tendinopathies.

METHODS

A scientific literature search was conducted using the PubMed, Medline and PEDro electronic databases. The databases were searched since their inception until July 2021. The search was limited to English language articles. Different combinations of the terms and MeSH terms "tendinopathy", "tendinosis", "tendinitis", "hyaluronic acid", "hyaluronate", "infiltration", "hyaluronic injections", "viscosupplementation" connected with various boolean operators were used for other electronic databases.

RESULTS

One hundred and one records were identified from the selected databases plus three additional papers identified by the authors through other sources. After removing duplicated papers and title/abstract screening, 19 studies were included in our review (eight papers on shoulder, three on elbow, four on hand, one on knee, and three on ankle).

CONCLUSION

The results showed that none of the studies report severe adverse effects and most of them support the use of HA injections in tendinopathies, with a special attention to pain reduction and functional assessment. Further studies are warranted to better investigate effects and methods of administration of HA in tendinopathies.

Clinical Impact of Metabolic Syndrome on Eccentric Exercises for Chronic Insertional Achilles Tendinopathy

Metabolic syndrome is one factor known to contribute to the development of tendinopathies. The aim of this study was to compare the clinical outcomes of eccentric calf-muscle exercise for treatment of chronic insertional Achilles tendinopathy in patients with or without metabolic syndrome. Twenty-eight patients with chronic insertional Achilles tendinopathy and metabolic syndrome who performed eccentric calf-muscle exercise were retrospectively compared with 28 age- and sex-matched controls without metabolic syndrome. Comparisons between the 2 groups were made by evaluating the Visual Analog Scale for pain, patient satisfaction, and amount of pain medications needed during 3 months of follow-up. Two-way analysis of variance with repeated measures showed that the pain scales in the metabolic syndrome group were higher than those in the control group during the follow-up period (F[1,54] = 24.45, p < .001). The patient satisfaction ratings were lower and the amount of required pain medication was higher in the metabolic syndrome group (p < .001 and p < .001, respectively). Eccentric calf-muscle exercises for chronic insertional Achilles tendinopathy were less effective in patients with metabolic syndrome. Therefore, these patients should be managed with a combination of other treatment modalities rather than eccentric exercise alone.

Evaluation of short-term and residual effects of Kinesio taping in chronic lateral epicondylitis: A randomized, double-blinded, controlled trial

BACKGROUND

Lateral epicondylitis is degenerative tendinosis of the extensor carpi radialis brevis muscle and is the most common work/sports-related chronic musculoskeletal problem affecting the elbow.

PURPOSE

This study aimed to evaluate the short term and residual effectiveness of the Kinesio taping method on pain, grip force, quality of life, and functionality.

STUDY DESIGN

Randomized, double-blinded, controlled study.

METHODS

Subjects were 50 patients diagnosed with chronic unilateral lateral epicondylitis with a symptom duration of at least 12 weeks. During the first four weeks, the study group received a true inhibitor Kinesio taping while the control group received sham taping. In both groups, progressive stretching and strengthening exercises were given as a home program for six weeks. The primary outcome measure was the Numerical Rating Scale (NRS) for self-report of pain intensity; secondary outcome measures were Cyriax resistive muscle test evaluation, maximal grip strength, Patient- Rated Tennis Elbow Evaluation (PRTEE), and Short Form-36 (SF-36). After the treatment, patients were evaluated by the first assessor who was blinded to taping types.

RESULTS

There was a significant decrease in NRS scores overtime during the first four weeks in both groups (P < .001,) and effect sizes were large. There was no significant difference in Cyriax muscle resistance test maximal grip strength between groups (P > .05). However, there was a significant improvement in muscle strength of elbow extension and pronation in the study group detected in the intragroup analysis. Intragroup comparisons also showed a significant improvement in all subunits of the PRTEE and SF-36 except energy/vitality, social functioning, and pain in both groups (P < .05) with moderate to high effect sizes. PRTEE pain scores were significantly decreased in the study group compared to the placebo group (P < .05, d = 0.48).

CONCLUSION

The effects of Kinesio taping on muscle strength, quality of life, and function in chronic lateral epicondylitis are not superior to placebo. However, NRS scores showed that in the two weeks after Kinesio taping treatment, pain reduction persisted as a residual effect which may improve the exercise adherence and functionality.

The impact of type 2 diabetes on the development of tendinopathy

Tendinopathy is a chronic and often painful condition affecting both professional athletes and sedentary subjects. It is a multi-etiological disorder caused by the interplay among overload, ageing, smoking, obesity (OB) and type 2 diabetes (T2D). Several studies have identified a strong association between tendinopathy and T2D, with increased risk of tendon pain, rupture and worse outcomes after tendon repair in patients with T2D. Moreover, consequent immobilization due to tendon disorder has a strong impact on diabetes management by reducing physical activity and worsening the quality of life. Multiple investigations have been performed to analyse the causal role of the individual metabolic factors occurring in T2D on the development of tendinopathy. Chronic hyperglycaemia, advanced glycation end-products, OB and insulin resistance have been shown to contribute to the development of diabetic tendinopathy. This review aims to explore the relationship between tendinopathy and T2D, in order to define the contribution of metabolic factors involved in the degenerative process and to discuss possible strategies for the clinical management of diabetic tendinopathy.

Altered Differentiation of Tendon-Derived Stem Cells in Diabetic Conditions Mediated by Macrophage Migration Inhibitory Factor

The purpose of our study was to evaluate the role of macrophage migration inhibitory factor (MIF) in the differentiation of tendon-derived stem cells (TdSCs) under hyperglycemic conditions. In the in vivo experiment, rats were classified into diabetic (DM) and non-DM groups depending on the intraperitoneal streptozotocin (STZ) or saline injection. Twelve-week after STZ injection, the supraspinatus tendon was harvested and prepared for histological evaluation and real-time reverse transcription polymerase chain reaction for osteochondrogenic (aggrecan, BMP-2, and Sox9) and tenogenic (Egr1, Mkx, scleraxis, type 1 collagen, and Tnmd) markers. For the in vitro experiment, TdSCs were isolated from healthy rat Achilles tendons. Cultured TdSCs were treated with methylglyoxal and recombinant MIF or MIF gene knockdown to determine the effect of hyperglycemic conditions and MIF on the differentiation function of TdSCs. These conditions were classified into four groups: hyperglycemic-control group, hyperglycemic-recombinant-MIF group, hyperglycemic-knockdown-MIF group, and normal-control group. The mRNA expression of osteochondrogenic and tenogenic markers was compared among the groups. In the in vivo experiment, the mRNA expression of all osteochondrogenic and tenogenic differentiation markers in the DM group was significantly higher and lower than that in the non-DM group, respectively. Similarly, in the in vitro experiments, the expression of all osteochondrogenic and tenogenic differentiation markers was significantly upregulated and downregulated, respectively, in the hyperglycemic-control group compared to that in the normal-control group. The hyperglycemic-knockdown-MIF group demonstrated significantly decreased expression of all osteochondrogenic differentiation markers and increased expression of only some tenogenic differentiation markers compared with the hyperglycemic-control group. In contrast, the hyperglycemic-recombinant-MIF group showed significantly increased expression of all osteochondrogenic differentiation markers, but no significant difference in any tenogenic marker level, compared to the hyperglycemic-control group. These results suggest that tendon homeostasis could be affected by hyperglycemic conditions, and MIF appears to alter the differentiation of TdSCs via enhancement of the osteochondrogenic differentiation in hyperglycemic conditions. These are preliminary findings, and must be confirmed in a further study.

Does glucocorticoid exposure explain the association between metabolic dysfunction and tendinopathy?

BACKGROUND

While metabolic health is acknowledged to affect connective tissue structure and function, the mechanisms are unclear. Glucocorticoids are present in almost every cell type throughout the body and control key physiological processes such as energy homeostasis, stress response, inflammatory and immune processes, and cardiovascular function. Glucocorticoid excess manifests as visceral adiposity, dyslipidaemia, insulin resistance, and type 2 diabetes. As these metabolic states are also associated with tendinopathy and tendon rupture, it may be that glucocorticoids excess is the link between metabolic health and tendinopathy.

OBJECTIVE

To synthesise current knowledge linking glucocorticoids exposure to tendon structure and function.

METHODS

Narrative literature review.

RESULTS

We provide an overview of endogenous glucocorticoid production, regulation, and signalling. Next we review the impact that oral glucocorticoid has on risk of tendon rupture and the effect that injected glucocorticoid has on resolution of symptoms. Then we highlight the clinical and mechanistic overlap between tendinopathy and glucocorticoid excess in the areas of visceral adiposity, dyslipidaemia, insulin resistance and type 2 diabetes. In these areas, we highlight the role of glucocorticoids and how these hormones might underpin the connection between metabolic health and tendon dysfunction.

CONCLUSIONS

There are several plausible pathways through which glucocorticoids might mediate the connection between metabolic health and tendinopathy.