Imaging findings of spontaneous detachment of the deltoid muscle as a complication of massive rotator cuff tear

A tear at the origin of the deltoid muscle is uncommon and usually occurs as a complication of shoulder surgery. We report a case of spontaneous deltoid detachment as a complication of massive rotator cuff tear in a 70-year-old woman evaluated by standard radiographs, ultrasound, arthrography and MR-arthrography. We present the multimodality imaging findings with review of the literature. We found that ultrasound is an accurate modality in detecting and assessing spontaneous detachment of the deltoid muscle. As ultrasound is a noninvasive, low-cost, and universally available imaging modality we suggest using ultrasound as the first modality for evaluation of spontaneous detachment of the deltoid muscle.