The subtendinous suprascapularis muscle or supra-acromial bursa is located on the upper face of the acromion and usually does not communicate with the glenohumeral joint. Supra-acromial bursitis has not been receiving much attention from the literature and is still mainly described as reports of cases of presumptive diagnosis with no histopathological correlation. From the supra-acromial, non-supraclavicular bursa, fluid-filled masses located above the articular or distal acromioclavicular clavicle do not correspond to supra-acromial bursitis.
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