Radiographic and Magnetic Resonance Imaging-based Evaluation of Supraspinatus Impingement Syndrome – A Narrative Review

Shoulder pain is a common debilitating problem affecting both young as well as elderly people. Its prevalence varies from 6-11% in young adults to 16-25% in elderly. Supraspinatus Impingement syndrome is the most common impingement syndrome causing shoulder pain. Primary or secondary reduction of subacromial distance due to morphological differences of acromion, acromial osteophytes, superior migration of humeral head etc. are predisposing factor for supraspinatus impingement. The aim of this review article is to understand the relevant anatomy of subacromial space and review supraspinatus impingement syndrome and its association with subacromial distance and acromion morphology. Literature search was conducted on PubMed and Google Scholar databases using MeSH terms – 'subacromial distance', 'Supraspinatus Impingement syndrome', 'Acromion', 'MRI'. 8 studies from 2006 to 2021 have been included for review. It was observed that subacromial distance and lateral acromial angle are lower in patients with supraspinatus impingement compared to the general population. Whereas the acromion index is higher in impingement syndrome. Evaluation of supraspinatus impingement syndrome can be done reliably using specialized radiographic views and MRI. Extrinsic factors like reduced subacromial distance and acromion morphology are predisposing factors for impingement of supraspinatus tendon.