Deltoideal acromial enthesopathy in ankylosing spondylitis and in spondylarthropathies: Comment on the article by Lambert et al

Novel imaging modalities in spondyloarthritis

Novel imaging techniques have emerged in the field of spondyloarthritis. This article will cover the role of, and the sensitivity and specificity of magnetic resonance imaging (MRI) and ultrasound in the diagnosis and monitoring of axial and peripheral SpA. It will discuss how the definition of a 'positive MRI' of the sacroiliac joints and spine is evolving. Differential diagnoses of inflammatory lesions of both the sacroiliac joints and the spine are addressed due to their importance in image interpretation. The article will also discuss the role of sonography in assessing peripheral entheses, joints, tendon sheaths, nails and soft tissues. The utility for clinical as well as an outcome measure will be discussed. We finally aim to give guidance on when and how to use these new modalities and on how to analyse and interpret the imaging findings in daily practice.

Ultrasound of enthesopathy in rheumatic diseases

Enthesopathy is the pathologic change of the insertion of tendons, ligaments and joint capsules on the bone. It is a cardinal feature of spondyloarthropathies (SpA), but it can occur in other rheumatic disease. Recent studies using magnetic resonance imaging (MRI) and ultrasonography (US) have demonstrated that enthesopathy can often be asymptomatic, in both the axial and peripheral skeleton. Therefore, a systematic US study of peripheral entheses could be useful in the diagnostic process of patients with rheumatic diseases, in particular SpA. Recently, power Doppler US (PDUS) has been proved to be useful for differentiating mechanical/degenerative and inflammatory enthesopathy and for monitoring the efficacy of therapy. This article reviews the main histopathologic aspects of enthesopathy and describes the normal US features of enthesis and the basic US features of enthesopathy, in its various stages. The usefulness of US and PDUS in the diagnosis and assessment of enthesopathy is discussed on the basis of the literature and our experience.