Imaging Review of Subscapularis Tendon and Rotator Interval Pathology

As the largest rotator cuff muscle, the subscapularis plays a major role in stabilizing the glenohumeral joint, in conjunction with surrounding rotator cuff structures. Injury to the subscapularis tendon can be isolated, but more commonly is seen in conjunction with supraspinatus tendon pathology. Injury can be associated with biceps pulley instability, superior labral anterior-posterior (SLAP) tears, humeral head subluxation, and anterosuperior and coracoid impingements. The involvement of the rotator interval can lead to what is called “the hidden lesion,” due to its difficulty to diagnose during arthroscopy. Understanding the anatomical relations of the subscapularis tendon with the rest of the rotator cuff and rotator interval, as well as common patterns of injury that involve the subscapularis tendon, can aid in proper diagnosis of these injuries leading to prompt surgical repair. This review describes the anatomy of the subscapularis muscle and tendon, and the magnetic resonance imaging (MRI) patterns of subscapularis tendon injury.

Tendon and multiomics: advantages, advances, and opportunities

Tendons heal by fibrosis, which hinders function and increases re-injury risk. Yet the biology that leads to degeneration and regeneration of tendons is not completely understood. Improved understanding of the metabolic nuances that cause diverse outcomes in tendinopathies is required to solve these problems. ‘Omics methods are increasingly used to characterize phenotypes in tissues. Multiomics integrates ‘omic datasets to identify coherent relationships and provide insight into differences in molecular and metabolic pathways between anatomic locations, and disease stages. This work reviews the current literature pertaining to multiomics in tendon and the potential of these platforms to improve tendon regeneration. We assessed the literature and identified areas where ‘omics platforms contribute to the field: (1) Tendon biology where their hierarchical complexity and demographic factors are studied. (2) Tendon degeneration and healing, where comparisons across tendon pathologies are analyzed. (3) The in vitro engineered tendon phenotype, where we compare the engineered phenotype to relevant native tissues. (4) Finally, we review regenerative and therapeutic approaches. We identified gaps in current knowledge and opportunities for future study: (1) The need to increase the diversity of human subjects and cell sources. (2) Opportunities to improve understanding of tendon heterogeneity. (3) The need to use these improvements to inform new engineered and regenerative therapeutic approaches. (4) The need to increase understanding of the development of tendon pathology. Together, the expanding use of various ‘omics platforms and data analysis resulting from these platforms could substantially contribute to major advances in the tendon tissue engineering and regenerative medicine field.

Neovascularization in Meniscus and Tendon Pathology as a Potential Mechanism in Regenerative Therapies: Special Reference to Platelet-Rich Plasma Treatment

Neovascularization is a complex, multistep process that includes the activation of endothelial cells, degradation of the basement membrane surrounding the blood vessel, formation of tip cells, the sprouting, migration and proliferation of endothelial cells into the interstitial space, and then the generation of space in the matrix to allow for the formation of a new, proper lumen of a newly formed blood vessel. Abundant neovascularization can be found in tendinous tissue obtained from asymptomatic athletes or the meniscus early after the injury. The concept of neovascularization in musculoskeletal system disorders seems to be mainly associated with pain and poor clinical outcomes. On the one hand, this phenomenon allows for tissue regeneration, but on the other, it is present during the degeneration process in connective tissue. Establishing the current concept on neovascularization is also needed. A narrative review of the current literature was conducted using databases including Embase, PubMed and Cochrane. This review aims to investigate the exact role of the neovascularization process in tendon and meniscus lesions and its role as a potential target in clinics, specifically in platelet-rich plasma (PRP) therapy. The stabilization of the neovessels required to achieve the healed tissue, together with the standardization of the PRP injections, can offer an alternative future therapeutic approach for the treatment of tendinopathy and meniscal injuries.

Comparison Between Ultrasonography and Magnetic Resonance Imaging in Achilles Tendon

Purpose: This study aims was to compared the effectiveness of Magnetic Resonance Imaging (MRI) and Ultrasonography (US) imaging techniques in the diagnosis of tendon pathology. Method: The databases search of PubMed, Scopus, and Embase extracted 567 articles for a title and abstract review. After removing and evaluating, a total of 6 articles were collected. Results and conclusion: There are three views on the diagnosis of Achilles tendon (AT) by US and MRI: US has higher sensitivity and reliability than MRI; MRI is more effective than the US, and there is a similar diagnosis result between US and MRI. It may not be necessary to distinguish between the diagnostic role of US and MRI, since US and MRI tools can be used as effective means to provide valuable information for the diagnosis and treatment of AT.