Ultrasound morphology of the Achilles in asymptomatic patients with and without diabetes

Patellar tendon biomechanical and morphologic properties and their relationship to serum clinical variables in persons with prediabetes and type 2 diabetes

Tendon biomechanical properties and fibril organization are altered in patients with diabetes compared to healthy individuals, yet few biomarkers have been associated with in vivo tendon properties. We investigated the relationships between in vivo imaging-based tendon properties, serum variables, and patient characteristics across healthy controls (n = 14, age: 45 ± 5 years, body mass index [BMI]: 24 ± 1, hemoglobin A1c [HbA1c]: 5.3 ± 0.1%), prediabetes (n = 14, age: 54 ± 5 years, BMI: 29 ± 2; HbA1c: 5.7 ± 0.1), and type 2 diabetes (n = 13, age: 55 ± 3 years, BMI: 33 ± 2, HbA1c: 6.7 ± 0.3). We used ultrasound speckle-tracking and measurements from magnetic resonance imaging (MRI) to estimate the patellar tendon in vivo tangent modulus. Analysis of plasma c-peptide, interleukin-1β (IL-1β), IL-6, IL-8, tumor necrosis factor-α (TNF-α), adiponectin, leptin, insulin-like growth factor 1 (IGF-1), and C-reactive protein (CRP) was completed. We built regression models incorporating statistically significant covariates and indicators for the clinically defined groups. We found that tendon cross-sectional area normalized to body weight (BWN CSA) and modulus were lower in patients with type 2 diabetes than in healthy controls (p < 0.05). Our regression analysis revealed that a model that included BMI, leptin, high-density lipoprotein (HDL), low-density lipoprotein (LDL), age, and group explained ~70% of the variability in BWN CSA (R2 = 0.70, p < 0.001). For modulus, including the main effects LDL, groups, HbA1c, age, BMI, cholesterol, IGF-1, c-peptide, leptin, and IL-6, accounted for ~54% of the variability in modulus (R2 = 0.54, p < 0.05). While BWN CSA and modulus were lower in those with diabetes, group was a poor predicter of tendon properties when considering the selected covariates. These data highlight the multifactorial nature of tendon changes with diabetes and suggest that blood variables could be reliable predictors of tendon properties.

Power Doppler signal at the enthesis and bone erosions are the most discriminative OMERACT ultrasound lesions for SpA: results from the DEUS (Defining Enthesitis on Ultrasound in Spondyloarthritis) multicentre study

OBJECTIVES

To assess, in spondyloarthritis (SpA), the discriminative value of the Outcome Measures in Rheumatology (OMERACT) ultrasound lesions of enthesitis and their associations with clinical features in this population.

METHODS

In this multicentre study involving 20 rheumatology centres, clinical and ultrasound examinations of the lower limb large entheses were performed in 413 patients with SpA (axial SpA and psoriatic arthritis) and 282 disease controls (osteoarthritis and fibromyalgia). 'Active enthesitis' was defined as (1) power Doppler (PD) at the enthesis grade ≥1 plus entheseal thickening and/or hypoechoic areas, or (2) PD grade >1 (independent of the presence of entheseal thickening and/or hypoechoic areas).

RESULTS

In the univariate analysis, all OMERACT lesions except enthesophytes/calcifications showed a significant association with SpA. PD (OR=8.77, 95% CI 4.40 to 19.20, p<0.001) and bone erosions (OR=4.75, 95% CI 2.43 to 10.10, p<0.001) retained this association in the multivariate analysis. Among the lower limb entheses, only the Achilles tendon was significantly associated with SpA (OR=1.93, 95% CI 1.30 to 2.88, p<0.001) in the multivariate analyses. Active enthesitis showed a significant association with SpA (OR=9.20, 95% CI 4.21 to 23.20, p<0.001), and unlike the individual OMERACT ultrasound lesions it was consistently associated with most clinical measures of SpA disease activity and severity in the regression analyses.

CONCLUSIONS

This large multicentre study assessed the value of different ultrasound findings of enthesitis in SpA, identifying the most discriminative ultrasound lesions and entheseal sites for SpA. Ultrasound could differentiate between SpA-related enthesitis and other forms of entheseal pathology (ie, mechanical enthesitis), thus improving the assessment of entheseal involvement in SpA.

Ultrasonographic Finding of Contralateral Achilles Tendon in Patients With Acute Achilles Tendon Rupture: A Prospective Observational Study

OBJECTIVE

Although the incidence of contralateral Achilles tendon in patients with Achilles tendon rupture is higher than in the general population, there are no studies evaluating the status of the contralateral Achilles tendon. The aim of this study was to investigate the status of the contralateral Achilles tendon in patients with acute Achilles tendon rupture.

DESIGN

Prospective observational cohort study.

SETTING

University hospital foot and ankle clinic.

PARTICIPANTS

Seventy-five patients with acute Achilles tendon rupture who met the inclusion criteria.

INTERVENTION

Ultrasonography performed by an orthopedic surgeon who had 8 years of experience in musculoskeletal ultrasonography.

MAIN OUTCOME MEASURES

Ultrasonographic abnormalities of the contralateral Achilles tendon at the time of diagnosis of acute Achilles tendon rupture. Abnormalities were categorized as intratendinous lesions, peritendinous lesions, changes in retrocalcaneal bursa, and Achilles tendon thickening.

RESULTS

The maximal Achilles tendon thickness had a mean of 4.8 ± 1.0 mm. Nine patients (12%) showed ultrasonographic abnormalities on the contralateral Achilles tendon, and the presence of exertional pain was the sole associating variable with ultrasonographic abnormalities.

CONCLUSION

The prevalence of ultrasonographic abnormalities in the contralateral Achilles tendon shown in this study was not higher than that reported in healthy or asymptomatic Achilles tendon. Therefore, routine evaluation of the contralateral Achilles tendon is unnecessary at the time of acute Achilles tendon rupture.

Effect of Diabetes on Tendon Structure and Function: Not Limited to Collagen Crosslinking

Diabetes mellitus (DM) is associated with musculoskeletal complications-including tendon dysfunction and injury. Patients with DM show altered foot and ankle mechanics that have been attributed to tendon dysfunction as well as impaired recovery post-tendon injury. Despite the problem of DM-related tendon complications, treatment guidelines specific to this population of individuals are lacking. DM impairs tendon structure, function, and healing capacity in tendons throughout the body, but the Achilles tendon is of particular concern and most studied in the diabetic foot. At macroscopic levels, asymptomatic, diabetic Achilles tendons may show morphological abnormalities such as thickening, collagen disorganization, and/or calcific changes at the tendon enthesis. At smaller length scales, DM affects collagen sliding and discrete plasticity due to glycation of collagen. However, how these alterations translate to mechanical deficits observed at larger length scales is an area of continued investigation. In addition to dysfunction of the extracellular matrix, tendon cells such as tenocytes and tendon stem/progenitor cells show significant abnormalities in proliferation, apoptosis, and remodeling capacity in the presence of hyperglycemia and advanced glycation end-products, thus contributing to the disruption of tendon homeostasis and healing. Improving our understanding of the effects of DM on tendons-from molecular pathways to patients-will progress toward targeted therapies in this group at high risk of foot and ankle morbidity.

Human Achilles tendon mechanical behavior is more strongly related to collagen disorganization than advanced glycation end-products content

Diabetes is associated with impaired tendon homeostasis and subsequent tendon dysfunction, but the mechanisms underlying these associations is unclear. Advanced glycation end-products (AGEs) accumulate with diabetes and have been suggested to alter tendon function. In vivo imaging in humans has suggested collagen disorganization is more frequent in individuals with diabetes, which could also impair tendon mechanical function. The purpose of this study was to examine relationships between tendon tensile mechanics in human Achilles tendon with accumulation of advanced glycation end-products and collagen disorganization. Achilles tendon specimens (n = 16) were collected from individuals undergoing lower extremity amputation or from autopsy. Tendons were tensile tested with simultaneous quantitative polarized light imaging to assess collagen organization, after which AGEs content was assessed using a fluorescence assay. Moderate to strong relationships were observed between measures of collagen organization and tendon tensile mechanics (range of correlation coefficients: 0.570-0.727), whereas no statistically significant relationships were observed between AGEs content and mechanical parameters (range of correlation coefficients: 0.020-0.210). Results suggest that the relationship between AGEs content and tendon tensile mechanics may be masked by multifactorial collagen disorganization at larger length scales (i.e., the fascicle level).

Advanced glycation end productions and tendon stem/progenitor cells in pathogenesis of diabetic tendinopathy

Tendinopathy is a challenging complication observed in patients with diabetes mellitus. Tendinopathy usually leads to chronic pain, limited joint motion, and even ruptured tendons. Imaging and histological analyses have revealed pathological changes in various tendons of patients with diabetes, including disorganized arrangement of collagen fibers, microtears, calcium nodules, and advanced glycation end product (AGE) deposition. Tendon-derived stem/ progenitor cells (TSPCs) were found to maintain hemostasis and to participate in the reversal of tendinopathy. We also discovered the aberrant osteochondrogenesis of TSPCs in vitro. However, the relationship between AGEs and TSPCs in diabetic tendinopathy and the underlying mechanism remain unclear. In this review, we summarize the current findings in this field and hypothesize that AGEs could alter the properties of tendons in patients with diabetes by regulating the proliferation and differentiation of TSPCs in vivo.

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.

Diabetes and treatment with orally administrated corticosteroids negatively affect treatment outcome at follow-up after acute Achilles tendon rupture

PURPOSE

Studies investigating the influence of comorbidities on patient-reported outcomes after acute Achilles tendon ruptures (ATR) are lacking. In this study, the aim was to investigate the effect of comorbidity and medical treatment on the patient-reported outcome measure Achilles tendon total rupture score (ATRS).

METHODS

The study was performed as a registry study from the Danish Achilles tendon Database (DADB). In the DADB, ATRS was registered at baseline (prior to rupture), at 3-6 month, 1-year and 2-year follow-ups. The outcomes were ATRS at follow-up and the change in ATRS from baseline to follow-up. Variables of interest were diabetes, hypertension, rheumatic disease and treatment with orally administrated corticosteroids. Linear mixed-effects models including all follow-up time points in the same model were used adjusting for sex, age group, treatment (operative or non-operative) and the investigated comorbidities.

RESULTS

Data were collected from 2012 to 2019. Two thousand and four patients with ATR were included. Patients with the investigated comorbidities and treatment with orally administrated corticosteroid scored 10.6-19.1 points lower in mean ATRS at baseline (prior to rupture) compared to patients without the respective disease or treatment. At follow-up, patients with diabetes (mean difference, [95% CI]) (- 6.2, [- 11.7; - 0.8]; P = 0.03) and patients in treatment with orally administrated corticosteroids (- 10.9, [- 16.2; - 5.7]; P < 0.01) had a statistically significantly worse ATRS than patients without the respective disease. However, change in ATRS from baseline to follow-up was not affected. Hypertension and rheumatic disease did not affect ATRS at follow-up but had a positive effect on change in ATRS (4.3, [0.5; 8.1]; P = 0.03) and (12.0, [5.0; 19.9]; P < 0.01), respectively. No other statistically significant differences were found.

CONCLUSION

This study showed that patients with diabetes, hypertension, rheumatic disease and patients in treatment with orally administrated corticosteroids had a lower ATRS at baseline (prior to the rupture) when compared to patients without the respective disease or treatment. Diabetes and treatment with orally administrated corticosteroids did negatively affect ATRS at follow-up, but none of the investigated comorbidities or treatment with orally administrated corticosteroids did negatively affect change in ATRS from baseline to follow-up.

LEVEL OF EVIDENCE

Level III.

Achilles tendon degeneration on ultrasound in type 2 diabetic patients

Aim of study

The main goal of this study was to compare the various degenerative changes in the Achilles tendon of type 2 diabetic patients to that of controls. The influence of diabetic peripheral neuropathy, duration of diabetes mellitus, age, and body mass index on the occurrence of degenerative changes was also evaluated.

Materials and methods

The Achilles tendons of both limbs were evaluated with high-resolution ultrasound in 80 type 2 diabetics and 80 age/sex-matched controls. A 10 g Semmes Weinstein monofilament was used to examine for peripheral neuropathy. Anthropometric measurements and biochemical assessment of glycemic control (fasting plasma glucose and glycated hemoglobin) were also done.

Results

The mean age of type 2 diabetic subjects and healthy controls was 60.9 ± 10.3 years (range 41–79 years) and 61.0 ± 10.3 years (range 40–79 years), respectively (p = 0.963). The median duration of diabetes mellitus was 42.0 months (range = 1–456 months). The prevalence of degenerative changes (calcifications, disorganized fibers and/or hypoechoic foci) was significantly higher in type 2 diabetic subjects than controls in both the right (55.0% vs. 18.8%, p <0.001) and left (52.5% vs. 18.8%, p <0.001) feet.

Conclusion

The Achilles tendons of type 2 diabetic subjects have significantly more degenerative changes than their age/sex-matched controls in our locality. Disorganized Achilles tendon fibers occur significantly more often among male than female type 2 diabetic subjects. Disorganization of Achilles tendon fibers and hypoechoic foci are significantly more prevalent in type 2 diabetic subjects with peripheral neuropathy than those without peripheral neuropathy. Body mass index did not affect the occurrence of degenerative changes in the Achilles tendon of participants.

Heel pain in female patients with early knee osteoarthritis

Background

Multiple lower limb joint involvement is one of the most common and debilitating musculoskeletal conditions, while the complaints from both heel and knee pain are considered the most frequent. For that reason, in this cross-sectional study, the association between heel pain (HP) and early knee osteoarthritis (EKOA) was investigated; the most painful site and side of HP, the prevalence, and risk factors for disabling HP in patients with EKOA were identified.

Results

Bilateral HP (56%) and posterior HP (54%) were found to be the most prevalent complaints, and 66% of patients reported the HP to be non-disabling. There was a very high positive statistically significant correlation between the Manchester Foot Pain Disability Index (MFPDI) and both the Health Assessment Questionnaire (HAQ) and the total Western Ontario and McMaster University Osteoarthritis (WOMAC) score (p ≤ 0.001), while there was a high negative statistically significant correlation between MFPDI and quadriceps angle of the most affected knee (p = 0.002). A higher total WOMAC score (OR 1.077, 95% CI 1.014 to 1.145) significantly increases the risk of developing disabling HP, while wearing 2–3-cm heels during the past month was found to be protective against the development of disabling HP (odds ratio < 1).

Conclusion

Disabling HP was present in a third of patients with EKOA and HP, and it was associated with flat shoe wear as well as a high total WOMAC score. Also, it had a statistically significant correlation with varus knee mal-alignment. Furthermore, decreased functional ability in the presence of HP was found to lead to significant disability. Moreover, a striking finding in this study was the longer mean duration of HP compared to the duration of knee symptoms.

Outcome after acute Achilles tendon rupture is not negatively affected by female sex and age over 65 years

PURPOSE

Studies suggest that women have worse treatment outcome than men after acute Achilles tendon rupture (ATR). The aim of this study was to investigate if sex and age affect treatment outcome after ATR.

METHODS

The study was performed as a registry study in the Danish Achilles tendon Database. The primary outcome was change in the Achilles tendon Total Rupture Score (ATRS) from baseline to 4 months, 1 year and 2 years follow-up. Variables of interest were sex and age group (< 40 years, 40-65 years and > 65 years).

RESULTS

Data were collected from April 2012 to March 2018. Five-hundred and sixteen patients (416 men, 100 women) were included in the study population. At baseline, women scored 4.3 points lower in ATRS compared to men. No statistically significant difference between the sexes regarding change in ATRS were found. Women scored statistically significantly less in absolute ATRS at 1 year follow-up (mean difference 9.4; 95% CI 3.8, 14.9; P = 0.03). Patients older than 65 years scored statistically significantly more in ATRS change compared to patients between 40-65 years (mean difference 12.8; 95% CI 6.1-19.5; P < 0.001).

CONCLUSION

This study did not show a statistically significant or clinically relevant difference between the sexes in ATRS change from baseline to follow-up. The mean difference in ATRS change between patients older than 65 years and patients between 40-65 years was clinically relevant with better outcome for patients older than 65 years. When comparing ATRS between groups with an unequal sex distribution, the findings of a baseline difference and a difference in absolute ATRS at 1 year follow-up between the sexes, advocate for reporting of sex-specific data or for use of change in ATRS from baseline to follow-up instead of absolute ATRS.

LEVEL OF EVIDENCE

Level III.

Sonoelastographic Evaluation of the Achilles Tendon in Patients With Type 2 Diabetes Mellitus

Diabetic foot is one of the dreaded complications of diabetes mellitus (DM). Alterations of the Achilles tendon (AT) may contribute to development of foot ulcers in diabetic patients. We evaluated the sonoelastographic abnormalities of the AT in 61 healthy volunteers and 81 patients with type 2 DM. The patients were further divided into those with and without peripheral neuropathy (PN). The AT thickness was measured in the proximal, middle and distal portions. Alterations in echo pattern were noted. The patients were found to have thicker tendons than the healthy volunteers (p < 0.01). Alterations in the echo pattern of the AT were more common in patients compared with healthy volunteers (p < 0.01). The shear wave velocity in the distal one-third of the AT was measured using shear wave elasticity imaging. Mean shear wave velocity values obtained were lower in patients compared with healthy volunteers (p < 0.001). No significant difference was found in the sonoelastographic findings of the AT in patients with and without PN. We conclude that there is softening, thickening and alterations in echo pattern of the AT in the form of hypoechogenicity, loss of fibrillar pattern and calcification at insertion in patients with type 2 DM, and these alterations could occur independent of onset of PN.

[CME Sonography 93: Ultrasound of the Enthesis - Not Every "Enthesitis" Signals a Spondyloarthritis]

CME Sonography 93: Ultrasound of the Enthesis - Not Every "Enthesitis" Signals a Spondyloarthritis Abstract. In this CME we will focus on the ultrasound anatomy of the enthesis. In addition, we describe the terms enthesopathy and enthesitis and discuss related differential diagnostic considerations. It is important to know all the diseases that can manifest themselves at the enthesis, so that diagnoses can be made, and patients classified correctly. At this point it is worth mentioning that the findings of enthesitis do not necessarily need to be associated with spondylarthritis.

Effects of Type II Diabetes Mellitus on Tendon Homeostasis and Healing

Over 300,000 tendon repairs are performed annually in the United States to repair damage to tendons as a result of either acute trauma or chronic tendinopathy. Individuals with type II diabetes mellitus (T2DM) are four times more likely to experience tendinopathy, and up to five times more likely to experience a tendon tear or rupture than non-diabetics. As nearly 10% of the US population is diabetic, with an additional 33% pre-diabetic, this is a particularly problematic health care challenge. Tendon healing in general is challenging and often unsatisfactory due to the formation of mechanically inferior scar-tissue rather than regeneration of native tendon structure. In T2DM tendons, there is evidence of an amplified scar tissue response, which may be associated with the increased the risk of rupture or impaired restoration of range of motion. Despite the dramatic effect of T2DM on tendon function and outcomes following injury, there are few therapies available to promote improved healing in these patients. Several recent studies have enhanced our understanding of the pro-inflammatory environment of T2DM healing and have assessed potential treatment approaches to mitigate pathological progression in pre-clinical models of diabetic tendinopathy. This review discusses the current state of knowledge of diabetic tendon healing from molecular to mechanical disruptions and identifies promising approaches and critical knowledge gaps as the field moves toward identification of novel therapeutic strategies to maintain or restore tendon function in diabetic patients. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:13-22, 2020.

Normal Ultrasonographic Parameters of the Posterior Tibial, Peroneal, and Achilles Tendons

Tendinopathy of the foot and ankle is common and can lead to pain or functional limitations. The most frequently affected tendons in the foot and ankle are the posterior tibial, peroneal, and Achilles. We used ultrasound to determine normal values for these tendons. From 2015 to 2016, a prospective, standardized bilateral lower extremity ultrasound examination protocol was performed by a musculoskeletal ultrasonographer of the 4 tendons and above and below the malleoli as appropriate. A total of 199 patients with 398 extremities were identified, consented, and participated in the study. Most tendons were normally distributed. The average size of the tendons was as follows: Achilles 5.0 mm (range 2.8-11.2 mm); peroneus long above the malleolus 2.1 mm (range 0.7-3.6 mm), below the malleolus 2.9 mm (range 0.8-6.3 mm); peroneus brevis above the malleolus 1.2 cm (range 0.3-4.0 mm), below the malleolus 1.3 mm (range 0.5-4.8 mm); posterior tibial tendon above the malleoli 3.7 mm (range 1.9-8.1 mm), below the malleolus 4.6 cm (range 1.8-11.8 mm). Standard deviations and distribution curves were similarly calculated for each tendon. This baseline data can assist clinicians in their diagnostic ability with ultrasound. Given its low cost, lack of ionizing radiation and dynamic ability along with an improved understanding of normative data it may become an increasingly used diagnostic modality. Levels of Evidence: Level II: Diagnostic.

Impaired function of tendon-derived stem cells in experimental diabetes mellitus rat tendons: implications for cellular mechanism of diabetic tendon disorder

Background

Patients with diabetes mellitus (DM) often suffered with many musculoskeletal disorders, such as tendon rupture and tendinopathy. However, the understanding of the pathogenesis of these alternations is limited. This study was designed to investigate the role of tendon-derived stem cells (TDSCs) in histopathological alterations of DM tendons.

Methods

Forty-two SD rats were randomly and equally divided into a diabetes group (DG) and control group (CG). DM was induced by streptozotocin (65 mg/kg). The patellar tendons were isolated at weeks 1, 2, and 4 for histological analysis. TDSCs were isolated at week 2 for osteo-chondrogenic differentiation analysis. Mann-Whitney U test was used with SPSS. p < 0.050 was statistically significant.

Results

Micro-tears of collagen fibers and altered appearance of tendon cells were observed in DG tendons. DG tendons exhibited significantly higher expression of OPN, OCN, SOX9, and Col II and decreased expression of Col I and tenomodulin (TNMD) at week 2. Diabetic TDSCs (dTDSCs) demonstrated significantly decreased proliferation ability and increased osteogenic and chondrogenic differentiation ability. Osteo-chondrogenic markers BMP2, ALP, OPN, OCN, Col II, and SOX9 were also significantly increased while tenogenic markers Col I and TNMD were decreased in dTDSCs.

Conclusion

These results suggested the erroneous differentiation of dTDSCs might account for the structural and non-tenogenic alternations in DM tendons, which provided new cues for the pathogenesis of tendon disorders in DM.

Electronic supplementary material

The online version of this article (10.1186/s13287-018-1108-6) contains supplementary material, which is available to authorized users.

Plantar fascia enthesopathy is highly prevalent in diabetic patients without peripheral neuropathy and correlates with retinopathy and impaired kidney function

BACKGROUND

Aim of this study was to evaluate the prevalence of plantar fascia (PF) enthesopathy in Type 2 diabetes mellitus (T2DM) patients without distal peripheral neuropathy (DPN).

METHODS

We recruited 50 T2DM patients without DPN and 50 healthy controls. DPN was excluded using the Michigan Neuropathy Screening Instrument (MNSI). All patients underwent a bilateral sonographicevaluation of the enthesealportion of the PF.

RESULTS

PF thickness was significantly higher in T2DM patients (p<0.0001). T2DM patients presented a higher prevalence of entheseal thickening (p = 0.002), enthesophyte (p = 0.02) and cortical irregularity (p = 0.02). The overall sum of abnormalities was higher in T2DM patients (p<0.0001), as was the percentage of bilateral involvement (p = 0.005). In a logistic regression analysis, retinopathy predicted entheseal thickening (OR 3.5, p = 0.05) and enthesophytes (OR 5.13, p = 0.001); reduced eGFR predicted enthesophytes (OR 2.93, p = 0.04); body mass index (BMI) predicted cortical irregularity (OR 0.87, p = 0.05); mean glucose predicted enthesophyte (OR 1.01, p = 0.03); LDL cholesterol predicted cortical irregularity (OR 0.98, p = 0.02).

CONCLUSIONS

Our data suggest that T2DM is associated with PF enthesopathyindependently of DPN.

High Prevalence of Achilles Tendon Enthesopathic Changes in Patients with Type 2 Diabetes Without Peripheral Neuropathy

BACKGROUND

Metabolic disorders are known to alter the mechanical properties of tendons. We sought to evaluate the prevalence of asymptomatic Achilles tendon enthesopathic changes in patients with type 2 diabetes mellitus (T2DM) without peripheral neuropathy.

METHODS

We recruited 43 patients with T2DM and 40 controls. Neuropathy was excluded with the Michigan Neuropathy Scoring Instrument. Bilateral ultrasonography of the Achilles tendon enthesis was performed.

RESULTS

Patients with T2DM had a higher prevalence of hypoechogenicity (26.7% versus 2.5%; P = .0001), entheseal thickening (24.4% versus 8.7%; P = .007), and enthesophytes (74.4% versus 57.5%; P = .02). No differences were found in the number of patients with erosions (1.2% versus 0%; P > .99), cortical irregularities (11.6% versus 3.7%; P = .09), bursitis (5.8% versus 3.7%; P = .72), or tears (2.3% versus 1.2%; P > .99). The mean ± SD sum of abnormalities was higher in patients with T2DM (1.5 ± 1.1 versus 0.7 ± 0.6; P < .0001), as was the percentage of bilateral involvement (72.1% versus 45.0%; P = .01). Mean ± SD thickness did not differ between patients and controls (4.4 ± 1.1 mm versus 4.2 ± 0.8 mm; P = .07).

CONCLUSIONS

According to our data, there is an elevated prevalence of asymptomatic Achilles tendon enthesopathic changes in patients with T2DM independent of peripheral neuropathy.

Tendinopathy in diabetes mellitus patients-Epidemiology, pathogenesis, and management

Chronic tendinopathy is a frequent and disabling musculo-skeletal problem affecting the athletic and general populations. The affected tendon is presented with local tenderness, swelling, and pain which restrict the activity of the individual. Tendon degeneration reduces the mechanical strength and predisposes it to rupture. The pathogenic mechanisms of chronic tendinopathy are not fully understood and several major non-mutually exclusive hypotheses including activation of the hypoxia-apoptosis-pro-inflammatory cytokines cascade, neurovascular ingrowth, increased production of neuromediators, and erroneous stem cell differentiation have been proposed. Many intrinsic and extrinsic risk/causative factors can predispose to the development of tendinopathy. Among them, diabetes mellitus is an important risk/causative factor. This review aims to appraise the current literature on the epidemiology and pathology of tendinopathy in diabetic patients. Systematic reviews were done to summarize the literature on (a) the association between diabetes mellitus and tendinopathy/tendon tears, (b) the pathological changes in tendon under diabetic or hyperglycemic conditions, and (c) the effects of diabetes mellitus or hyperglycemia on the outcomes of tendon healing. The potential mechanisms of diabetes mellitus in causing and exacerbating tendinopathy with reference to the major non-mutually exclusive hypotheses of the pathogenic mechanisms of chronic tendinopathy as reported in the literature are also discussed. Potential strategies for the management of tendinopathy in diabetic patients are presented.

Achilles or biceps tendon rupture in women and men with type 2 diabetes: A population-based case-control study

AIMS

Previous studies suggest that diabetes causes alterations in tendon collagen structure, but evidence on how such findings translate into clinical practice is scarce. We aimed to analyze the association between type 2 diabetes and the risk of tendon rupture.

MATERIALS AND METHODS

We conducted a matched case-control analysis using the UK-based Clinical Practice Research Datalink. Cases (n=7895) were aged 30-89years and had an incident diagnosis of Achilles- or biceps tendon rupture between 1995 and 2013. In multivariable logistic regression analyses we compared the odds of tendon rupture between patients with or without type 2 diabetes, in men and women separately, and taking into account diabetes severity (HbA1c), duration, and antidiabetic drug treatment.

RESULTS

Within 165 (7.1%) female cases with type 2 diabetes, odds ratios (ORs) were increased with poorer diabetes control (OR 2.03, 95% CI 1.20-3.41, HbA1c ≥9% [≥75mmol/mol]), longer disease duration (OR 1.60, 95% CI 0.93-2.74, ≥10years), and current insulin use (OR 2.25, 95% CI 1.30-3.90, ≥20 prescriptions). Among 372 (6.7%) male cases, there was no effect of type 2 diabetes on the risk of tendon rupture.

CONCLUSIONS

Our results suggest that the risk of tendon ruptures may be increased in women with poorly controlled type 2 diabetes, but not in men.

Achilles tendinopathy in elderly subjects with type II diabetes: the role of sport activities

BACKGROUND

Exercise is an important therapeutic tool in the management of diabetes in older people. Aim of this study was to assess the relationship among type II diabetes, sport, overweight, and symptomatic Achilles tendinopathy in elderly subjects.

METHODS

Thirty-eight patients suffering from Achilles tendinopathy and thirty-eight controls were enrolled. The prevalence of diabetes and sport practice as well as BMI and Glycated Hemoglobin (HbA1c) values were registered. An ultrasound evaluation of Achilles tendon was performed.

RESULTS

Patients showed an increased prevalence of diabetes (42 vs. 13.1 %, p = 0.004), and practice of sport (60.5 vs. 28.9 %, p = 0.0001), and higher BMI values (26.8 ± 3 vs. 24.8 ± 2.3, p = 0.001). Sonographic abnormalities, being diagnostic criteria, were present in all the patients with Achilles tendinopathy, but signs of degeneration were also found in 36.8 % of asymptomatic controls. Symptomatic subjects with diabetes, compared to those without, showed a higher prevalence of severe degeneration (75 vs. 36.3 %, p = 0.01). HbA1c values were significantly lower in sport practitioners, both diabetics and non-diabetics. Moreover, patients practicing sport showed a trend towards lower BMI values, compared to the sedentary counterpart.

CONCLUSIONS

Sport practice in elderly diabetics provides relevant metabolic advantages, reducing HbA1c and BMI. However, some sport activities (e.g., speed walking, jogging or tennis) can expose to the risk of Achilles tendinopathy. So, sport practice should be encouraged, but practitioners should follow individual training programs and be submitted to periodic sonographic controls.

Hormones and tendinopathies: the current evidence

BACKGROUND

Tendinopathies negatively affect the quality of life of millions of people, but we still do not know the factors involved in the development of tendon conditions.

SOURCES OF DATA

Published articles in English in PubMed and Google Scholar up to June 2015 about hormonal influence on tendinopathies onset. One hundred and two papers were included following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

AREAS OF AGREEMENT

In vitro and in vivo, tenocytes showed changes in their morphology and in their functional properties according to hormonal imbalances.

AREAS OF CONTROVERSY

Genetic pattern, sex, age and comorbidities can influence the hormonal effect on tendons.

GROWING POINTS

The increasing prevalence of metabolic disorders prompts to investigate the possible connection between metabolic problems and musculoskeletal diseases.

AREAS TIMELY FOR DEVELOPING RESEARCH

The influence of hormones on tendon structure and metabolism needs to be further investigated. If found to be significant, multidisciplinary preventive and therapeutic strategies should then be developed.

Acquired midfoot deformity and function in individuals with diabetes and peripheral neuropathy

BACKGROUND

Diabetes mellitus related medial column foot deformity is a major contributor to ulceration and amputation. However, little is known about the relationship between medial column alignment and function and the integrity of the soft tissues that support and move the medial column. The purposes of this study were to determine the predictors of medial column alignment and function in people with diabetes and peripheral neuropathy.

METHODS

23 participants with diabetes and neuropathy had radiographs, heel rise kinematics, magnetic resonance imaging and isokinetic muscle testing to measure: 1) medial column alignment (Meary's angle--the angle between the 1st metatarsal longitudinal axis and the talar head and neck), 2) medial column function (forefoot relative to hindfoot plantarflexion during heel rise), 3) intrinsic foot muscle and fat volume, ratio of posterior tibialis to flexor digitorum tendon volume, 4) plantar fascia function (Meary's angle change from toes flat to extended) and 5) plantarflexor peak torque. Predictors of medial column alignment and function were determined using simultaneous entry multiple regression.

FINDINGS

Posterior tibialis to flexor digitorum tendon volume ratio and intrinsic foot muscle volume were significant predictors of medial column alignment (P<.05), accounting for 44% of the variance. Intrinsic foot fat volume and plantarflexor peak torque were significant predictors of medial column function (P<.05), accounting for 37% of the variance.

INTERPRETATION

Deterioration of medial column supporting structures predicted alignment and function. Prospective research is required to monitor alignment, structure, and function over time to inform early intervention strategies to prevent deformity, ulceration, and amputation.

Complications of Tendon Surgery in the Foot and Ankle

This article discusses four subsets of patients that have an increased risk of complications from tendon surgery in the foot and ankle: smokers, diabetics, and patients with peroneal or Achilles tendon pathology. Very little has been published on the complications of other tendon surgeries in the foot and ankle other than Achilles tendon repair. Data can be extrapolated from the general orthopedic literature and animal studies to help guide therapy and treatment options. The foot and ankle surgeon must take into account the entirety of the history and physical examination to develop a treatment plan that optimizes each patient's chance for a complication-free recovery.

Real-time sonoelastography and ultrasound evaluation of the Achilles tendon in patients with diabetes with or without foot ulcers: a cross sectional study

BACKGROUND

Diabetes mellitus (DM) is an endocrine disease characterized by metabolic abnormalities and long-term complications. The Achilles tendon (AT) plays an important role in foot biomechanics. We aimed to investigate the effect of DM on the Achilles tendon, which may contribute to long-term complications in the foot-ankle complex.

METHODS

Seventy-eight patients with diabetes, with (35 patients, group I) or without (43 patients, group II) foot ulcers were recruited from the endocrinology clinic. Thirty-three age-, gender-, and BMI-matched healthy individuals were selected as controls. All participants underwent ultrasonography and sonoelastography of their AT in order to evaluate Achilles tendon thickness (ATT) and stiffness (ATS). Each patient was also tested for fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1C) as a measure of diabetes control. Other chronic complications were also evaluated in all patients with diabetes.

RESULTS

The AT was significantly thicker in group I compared to group II and the controls. HbA1C, FPG, and duration of diabetes were higher in group I. We observed that ATT was positively correlated with neuropathy, retinopathy, nephropathy, peripheral arterial disease and coronary arterial disease in group II while this correlation was not detected in group I. ATS was reduced in group I more than group II and control groups.

CONCLUSION

Changes in the structure of the AT may precede foot ankle disorders in patients with diabetes. This is the first study that reported the results of sonoelastosonography of AT in patients with diabetes and revealed the correlation between ATT and other chronic complications of diabetes.

Entheseal involvement in systemic disorders

The objective of this study is to review the data on entheseal involvement in systemic disorders. A Pubmed search utilizing the indexing terms "enthesis" and "enthesitis" was conducted and the data pertinent to the aim of the review was extracted and organized in accordance with the preplanned structure of the manuscript. A number of cadaver-based studies, as well as studies using ultrasonography and magnetic resonance imaging, have detailed new distinct aspects of enthesis physiology and pathology in a variety of rheumatic and non-rheumatic systemic disorders. Major progress has been done in characterization of separate components of the enthesis organ, imaging of entheses, elaboration of the role and features of entheseal disease in spondyloarthropathies, juvenile idiopathic arthritis, osteoarthritis, familial Mediterranean fever, hyperuricemia, and other systemic conditions. The knowledge acquired and summarized herein shows that entheses can be affected in various ways in variety of medical disorders with different pathogenesis. Better understanding of the risk factors, mechanisms and natural history of enthesopathies is warranted. The current progress in the understanding of entheseal involvement in systemic disorders represents just the first step in resolving the entheses-related enigmas.

Epidemiology of posterior heel pain in the general population: cross-sectional findings from the clinical assessment study of the foot

Objective

To identify the population prevalence of posterior heel pain (HP), related disability, and associated factors.

Methods

A total of 9,334 adults ages ≥50 years were mailed a questionnaire. Participants reporting foot pain in the last month shaded the foot pain location on a manikin. The Manchester Foot Pain and Disability Index assessed disabling foot pain. Population prevalence of any, bilateral, and disabling posterior HP was estimated using weighted logistic regression accounting for nonresponse. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated between posterior HP and age, sex, neighborhood deprivation, occupational class (professional, intermediate, and manual), body mass index (BMI, kg/m²), physical activity, heel height, and diabetes mellitus.

Results

A total of 5,109 questionnaires were received (adjusted response 56%). Six hundred seventy‐five respondents (13%) reported posterior HP, of whom 382 had bilateral symptoms. A total of 398 (8%) reported disabling posterior HP. Posterior HP in either foot was associated with increasing BMI (25.0–29.9 [OR 1.58], 30.0–34.9 [OR 2.13], and ≥35.0 [OR 4.09]) and with manual occupations (OR 1.96, 95% CI 1.47–2.62). Bilateral posterior HP was associated with increasing BMI (25.0–29.9 [OR 1.79], 30.0–34.9 [OR 2.43], and ≥35.0 [OR 5.79]), diabetes mellitus (OR 1.48, 95% CI 1.07–2.05), and manual occupations (OR 2.21, 95% CI 1.48–3.30). Disabling posterior HP was associated with increasing BMI (25.0–29.9 [OR 1.44], 30.0–34.9 [OR 2.50], and ≥35.0 [OR 4.69]), age (≥75 years OR 1.41, 95% CI 1.01–1.96), manual occupations (OR 1.97, 95% CI 1.35–2.88), and diabetes mellitus (OR 1.56, 95% CI 1.04–1.95). High physical activity was negatively associated with posterior HP in either heel (OR 0.43, 95% CI 0.33–0.56), bilateral posterior HP (OR 0.35, 95% CI 0.25–0.49), and disabling posterior HP (OR 0.33, 95% CI 0.23–0.46).

Conclusion

Posterior HP is prevalent and associated with obesity, manual occupations, and physical inactivity. Prospective studies should assess the roles of obesity in causation and weight loss in treatment.

Alterations of tendons in diabetes mellitus: what are the current findings?

As a connective tissue, tendon connects the muscle and bone, and plays the key role in the locomotor system. Some previous studies have shown the pathological alternations in diabetic tendons, which might result in the structural and functional changes, and even accelerate the process of diabetic foot. In this review, we examined the current findings of the diabetic tendons in the form of various aspects, and summarized the clinical presentation, imaging, biomechanical, histopathological, cellular and molecular abnormalities in the diabetic tendons. The progress of diabetic tendon damage is complicated and the main hypotheses include the excessive accumulation of AGEs, the altered inflammatory response, neovascularization and insensitive neuropathy. However, the cellular and molecular mechanisms of these alterations are still ambiguous. Tendon stem/progenitor cells (TSPCs) have been discovered to play important roles in both tendon physiology and tendon pathology. Recently, we identified TSPCs from patellar tendons in our well-established diabetic rat model and found impaired tenogenic differentiation potential of these cells. We proposed a new hypothesis that the impaired cell functions of diabetic TSPCs might be the underlying cellular and molecular mechanism of the diabetic tendon alternations. These findings should be helpful to establish a better therapeutic strategy for diabetic tendon repair and regeneration.

Achilles tendons in people with type 2 diabetes show mildly compromised structure: an ultrasound tissue characterisation study

BACKGROUND

Musculotendinous overuse injuries are prevalent in people with type 2 diabetes. Non-enzymatic glycosylation of collagen resulting in tendon stiffening may play a role. In this case-control study we determined whether patients with diabetes had poorer ultrasonographic structure in their Achilles tendons compared to age-matched controls.

METHODS

People with type 1 diabetes or type 2 diabetes, and age-matched controls, had computerised ultrasound tissue characterisation of both Achilles tendons. In contiguous ultrasonographic images of the tendon, echopatterns were quantified and categorised into four echo-types. Tendon abnormality was quantified as sum of echo-types III+IV. Furthermore, skin autofluorescence (AF) of the forearm (AF-value) was gathered.

RESULTS

Twenty four type 2 diabetes patients, 24 controls, 24 type 1 diabetes patients and 20 controls were included. AF-value was higher in type 1 diabetes (1.55±0.17) than in their controls (1.39±0.18, p<0.001) and in type 2 diabetes (2.28±0.38) compared to their controls (1.84±0.32, p<0.001) Achilles tendons of type 2 diabetes patients contained more echo-types III+IV (14.1±7.9%) than matched controls (8.0±5.4%, p<0.001). There was a trend towards a difference in echo-types III+IV between type 1 diabetes patients (9.5±5.3%) and their controls (6.5±3.7%, p=0.055). In a stepwise linear regression analysis, body mass index (BMI) was moderately associated with tendon abnormality in patients with diabetes and controls (β=0.393, p<0.001).

CONCLUSIONS

Type 2, and possibly type 1, diabetes patients showed poorer ultrasonographic Achilles tendon structure that may be a risk factor for tendinopathy. Although markers for accumulation of advanced glycation end products were elevated in both diabetes populations, only BMI was associated with these abnormalities.

TRIAL REGISTRATION NUMBER

NTR2209.