Intratendinous tears of the Achilles tendon - a new pathology? Analysis of a large 4-year cohort

Ultrasound assessment of acute Achilles tendon rupture and measurement of the tendon gap

Achilles tendon rupture is a common sports-related injury which can carry significant morbidity to patients. Ultrasound remains the workhorse of imaging as it can confirm and localise the extent of Achilles tendon injury. The sonographic anatomy, both normal and ruptured sonographic appearances, as well as sonographic technique must be appreciated to accurately image and report findings, critical to patient management. Particular attention should be applied to the measurement of the diastasis between acutely ruptured tendon ends as this information can assist with informing the decision of conservative vs. operative management. Further work is necessary to standardise the measurement technique including correlating the degree of plantarflexion of the foot with the sonographic tendon gap measures.

Ultrasound Measurement of Local Deformation in the Human Free Achilles Tendon Produced by Dynamic Muscle-Induced Loading: A Systematic Review

Achilles tendinopathy is the most prevalent lower limb tendinopathy, yet it remains poorly understood, with mismatches between observed structure and reported function. Recent studies have hypothesised that Achilles tendon (AT) healthy function is associated with variable deformation across the tendon width during use, focusing on quantifying sub-tendon deformation. Here, the aim of this work was to synthesise recent advances exploring human free AT tissue-level deformation during use. Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, PubMed, Embase, Scopus and Web of Science were systematically searched. Study quality and risk of bias were assessed. Thirteen articles were retained, yielding data on free AT deformation patterns. Seven were categorised as high-quality and six as medium-quality studies. Evidence consistently reports that healthy and young tendons deform non-uniformly, with the deeper layer displacing 18%-80% more than the superficial layer. Non-uniformity decreased by 12%-85% with increasing age and by 42%-91% in the presence of injury. There is limited evidence of large effect that AT deformation patterns during dynamic loading are non-uniform and may act as a biomarker of tendon health, risk of injury and rehabilitation impact. Better considered participant recruitment and improved measurement procedures would particularly improve study quality, to explore links between tendon structure, function, aging and disease in distinct populations.

An equine tendon model for studying intra-tendinous shear in tendons that have more than one muscle contribution

Human Achilles tendon is composed of three smaller sub-tendons and exhibits non-uniform internal displacements, which decline with age and after injury, suggesting a potential role in the development of tendinopathies. Studying internal sliding behaviour is therefore important but difficult in human Achilles tendon. Here we propose the equine deep digital flexor tendon (DDFT) and its accessory ligament (AL) as a model to understand the sliding mechanism. The AL-DDFT has a comparable sub-bundle structure, is subjected to high and frequent asymmetric loads and is a natural site of injury similar to human Achilles tendons. Equine AL-DDFT were collected and underwent whole tendon level (n=7) and fascicle level (n=7) quasi-static mechanical testing. Whole tendon level testing was performed by sequentially loading through the proximal AL and subsequently through the proximal DDFT and recording regional strain in the free structures and joined DDFT and AL. Fascicle level testing was performed with focus on the inter-sub-bundle matrix between the two structures at the junction. Our results demonstrate a significant difference in the regional strain between the joined DDFT and AL and a greater transmission of force from the AL to the DDFT than vice versa. These results can be partially explained by the mechanical properties and geometry of the two structures and by differences in the properties of the interfascicular matrices. In conclusion, this tendon model successfully demonstrates that high displacement discrepancy occurs between the two structures and can be used as an easy-access model for studying intra-tendinous shear mechanics at the sub-tendon level. STATEMENT OF SIGNIFICANCE: Our study provides a naturally occurring and easily accessible equine model to study the complex behaviour of sub-tendons within the human Achilles tendon, which is likely to play a critical role in the pathogenesis of tendon disease. Our results demonstrate that the difference in material stiffness between the equine AL and DDFT stems largely from differences in the inter-fascicular matrix and furthermore that differences in strain are maintained in distal parts of the tightly joined structure. Furthermore, our results suggest that distribution of load between sub-structures is highly dependent on the morphological relationship between them; a finding that has important implications for understanding Achilles tendon mechanical behaviour, injury mechanisms and rehabilitation.

MRI of the Achilles tendon - a comprehensive pictorial review. Part two

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The abnormalities on MRI should be correlated with the clinical findings.

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Higher signal of the Achilles tendon is a common postoperative finding.

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The fluid signal within the Achilles tendon graft indicates a rupture.

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Postoperative complications of Haglund’s syndrome should be assessed on MRI.

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Elongation of the Achilles tendon is seen after surgical or conservative treatment.

The most common disorder affecting the Achilles tendon is midportion tendinopathy. A focal fluid signal indicates microtears, which may progress to partial and complete rupture. Assessment of Achilles tendon healing should be based on tendon morphology and tension rather than structural signal. After nonoperative management or surgical repair of the Achilles tendon, areas of fluid signal is pathologic because it indicates re-rupture. A higher signal in the postoperative Achilles tendon is a common finding and is present for a prolonged period following surgical intervention and needs to be interpreted alongside the clinical appearance.

Partial Achilles Tendon Rupture-A Neglected Entity: A Narrative Literature Review on Diagnostics and Treatment Options

Partial ruptures in the Achilles tendon are rather uncommon and are often misinterpreted as aggravated Achilles tendinopathy, and not always considered as a differential diagnosis. The aim of this literature review was to characterize typical symptoms, to provide an overview of available diagnosis and treatment options, and to give reference points for future research. There were few studies and sparse knowledge of scientific value, making it difficult to give evidence-based recommendations. Based on the few studies and the authors’ clinical experience, a diagnosis should be based on a patient’s history with a typical sharp onset of pain and inability to fully load the tendon. Previous intratendinous cortisone injections might be present. Clinical findings are a localized tender region in the tendon and often weakness during heel raises. Ultrasound and Doppler examinations show a region with an irregular and bulging superficial tendon line, often together with localized high blood flow. Magnetic resonance Imaging (MRI) shows a hyperintense signal in the tendon on T1 and T2-weighted sequences. First-line therapy should be a conservative approach using a 2 cm heel lift for the first 6 weeks and avoiding tendon stretching (for 12 weeks). This is followed by a reduced heel lift of 1 cm and progressive tendon loading at weeks 7–12. After 12 weeks, the heel lift can be removed if pain-free, and the patient can gradually start eccentric exercises lowering the heel below floor level and gradually returning to previous sport level. If conservative management has a poor effect, surgical exploration and the excision of the partial rupture and suturing is required. Augmentation procedures or anchor applications might be useful for partial ruptures in the Achilles insertion, but this depends on the size and exact location. After surgery, the 12 to 14-week rehabilitation program used in conservative management can be recommended before the patient’s return to full tendon loading activities.

Distribution of the subtendons in the midportion of the Achilles tendon revealed in vivo on MRI

The aim of the study was to check if the subtendons of the Achilles tendon can be identified in vivo on MRI in the midportion of the tendon. The relation of the plantaris tendon to the Achilles tendon was also examined. A retrospective study of 200 MRI of ankle joints including the Achilles tendon was conducted. Statistical analysis of the correlation between the possibility of identifying the subtendons and the side, gender, presence of the central soleus tendon and plantaris tendon variation was performed. The inter-observer agreement between two reviewers in their evaluation of the subtendons was assessed using kappa statistics. The subtendon from the lateral head of the gastrocnemius muscle was identified in 65% (k = 0.63) and was located in the anterior part of the Achilles tendon. The subtendon from the soleus muscle was recognized in 12% (k = 0.75) comprising anterior part of the tendon. In 6% the subtendon from the medial head of the gastrocnemius muscle was identified (k = 0.58). The central soleus tendon was identified in 85% of cases. Statistical analysis shows the weak correlation of the presence of the central soleus tendon and the possibility of identifying the subtendon from the soleus muscle. The plantaris tendon was directly related to the insertion of the Achilles tendon in 42.5%. Identification of the subtendons of the Achilles tendon on MRI is challenging, and most often it is only possible to find the subtendon of the lateral head of the gastrocnemius muscle.

Minimum 3.5-year outcomes of operative treatment for Achilles tendon partial tears in the midportion and retrocalcaneal area

BACKGROUND

Achilles tendon partial tears are not easy to diagnose and to manage. Most frequently, they are located in the midportion and insertional area. These entities result from different pathologic pathways, and different treatment strategies are applied. The outcome is rarely investigated.

METHODS

This study includes patients who underwent surgery for partial tears in the midportion or retrocalcaneal Achilles tendon area between the years 2009 and 2015 by a single surgeon. Patients were prospectively assessed preoperatively and 3, 6, and 12 months postoperatively, using the VISA-A-G questionnaire. The final retrospective follow-up was performed after a minimum of 3.5 years postoperatively. Forty-eight Achilles tendon partial tears at the level of the retrocalcaneal bursa (impingement lesions) and 27 midportion Achilles tendon partial tears were identified. After applying rigorous exclusion criteria, 21 and 16 cases, respectively, remained for the final follow-up. Results were analysed by inferential and descriptive statistics.

RESULTS

The VISA-A-G outcome scores improved significantly from preoperative to 6 months, 12 months, and final postoperative assessment. Preoperatively, the average VISA-A-G score was 42.1 (range, 18-73) for patients operated for Achilles tendon partial tears at the level of the retrocalcaneal bursa and 44.6 (range, 10-73) for the midportion Achilles tendon partial tear group, respectively. At final follow-up 88.8 (range, 15 to 100) and 96.9 (range, 71 to 100) were scored in the respective treatment groups. A repeated measures ANOVA determined that mean performance levels showed a statistically significant difference between measurements (p < 0.001). There was no systematic effect found between groups (p = 0.836).

CONCLUSIONS

In Achilles tendon partial tears recalcitrant to conservative treatment, operative intervention is highly successful in most cases, irrespective of the level of the injury. Results were statistically equal when comparing the midportion and retrocalcaneal Achilles tendon partial tear groups.

TRIAL REGISTRATION

DRKS, DRKS00014266. Registered 06 April 2018. 'Retrospectively registered', https://www.drks.de/drks_web/navigate.do?navigationId=results .

Biological and chemical changes in fluoroquinolone-associated tendinopathies: a systematic review

INTRODUCTION

The present systematic review investigates the biological and chemical mechanisms that affect the health and structure of tendons following the use of fluoroquinolones (FQs).

SOURCES OF DATA

A total of 12 articles were included, organized, and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

AREAS OF AGREEMENT

Five mechanisms were identified: arrest of proliferation through a decreased activity of cyclin B, CDK-1, CHK-1, and increased PK-1; decrease tenocytes migration through decreased phosphorylation of FAK; decrease type I collagen metabolism through increased MMP-2; chelate effect on ions that influence epigenetics and several enzymes; fluoroquinolones-induced ROS (radical oxygen species) production in mitochondria.

AREAS OF CONTROVERSY

There is no definite structure-damage relationship. The dose-effect relationship is unclear.

GROWING POINTS

Knowing and defining the damage exerted by FQs plays a role in clinical practice, replacing FQs with other antibacterial drugs or using antioxidants to attenuate their pathological effects.

AREAS TIMELY FOR DEVELOPING RESEARCH

Clinical and basic sciences studies for each FQs are necessary.

Partial mid-portion Achilles tear resulting in substantial improvement in pain and function in an amateur long-distance runner

This case presents symptom resolution for a long-distance runner with chronic Achilles tendinopathy (AT), following a partial tear of his Achilles tendon. The patient reported a sudden pain during a morning run, with preserved function. Three hours postinjury, he was reviewed in a musculoskeletal clinic. An ultrasound scan confirmed a partial Achilles tear, associated with significant Doppler activity. His index of AT severity The Victorian Institute of Sports Assessment - Achilles Questionnaire (VISA-A) 4 hours postinjury was markedly higher compared with 2 weeks preinjury, indicating reduced symptom severity. A follow-up scan 4 weeks postinjury showed minimal mid-portion swelling and no signs of the tear. His VISA-A score showed continued symptom improvement. This case represents resolution of tendinopathic symptomatology post partial Achilles tear. While the natural histories of AT and Achilles tears remain unknown, this case may indicate that alongside the known role of loading, inflammation may be a secondary mediator central to the successful resolution of AT pain.

Achilles Pain, Stiffness, and Muscle Power Deficits: Midportion Achilles Tendinopathy Revision 2018

The Orthopaedic Section of the American Physical Therapy Association (APTA) has an ongoing effort to create evidence-based practice guidelines for orthopaedic physical therapy management of patients with musculoskeletal impairments described in the World Health Organization's International Classification of Functioning, Disability, and Health (ICF). The purpose of these revised clinical practice guidelines is to review recent peer-reviewed literature and make recommendations related to midportion Achilles tendinopathy. J Orthop Sports Phys Ther 2018;48(5):A1-A38. doi:10.2519/jospt.2018.0302.

Outcomes of prolotherapy for intra-tendinous Achilles tears: a case series

BACKGROUND

The intra-tendinous tear is a new pathology that is defined as a discontinuity of fibres situated entirely within the tendon. Prolotherapy involves injecting an irritant, such as hyperosmolar dextrose, to stimulate a tissue healing response and ultimately reduce pain.

METHODS

43 consecutive patients diagnosed with an intra-tendinous tear were included (27 males: 16 females, mean (SD) age 41 (11.3). Patients were injected with 0.4ml-1.5ml (mean 0.8ml) of 50% dextrose and 0.5% marcaine mixed in a 1:1 ratio. A 4-6 week period of walking boot immobilisation was followed by progressive rehabilitation (6-8 weeks). Outcomes were assessed with a VISA-A questionnaire at baseline, 3 months and a mean 12.6 (7.0) months post-treatment. Ultrasound scans were conducted before treatment and 5.2 (2.3) weeks later to assess sonographic changes.

RESULTS

30 patients (70%) responded with VISA-A scores increasing by 31 (30.5) points after 3 months (f=0.62, p<0.05) and by 40 (29.3) points after 12.60 (7.0) months (f=0.87, p<0.05). After 5.2 (2.3) weeks, echogenicity was significantly reduced (p<0.05) and 27% of tears were no longer detectable. No significant differences were observed in remaining tears with respect to tear size, tendon thickness or neovascularisation.

CONCLUSION

Treatment resulted in clinically significant improvements and controlled trials are warranted.

LEVEL OF EVIDENCE

IV.