The os acromiale is frequently missed during the MR interpretation due to its similar appearances to the acromioclavicular joint on coronal sequences as well as sagittal sequences.

Meticulous analysis shows that the os acromiale is more lateral on coronal sequences and more posterior on sagittal sequences than the acromioclavicular joint. The axial sequence will resolve this dilemma by showing on a single cut both structures with an acromioclavicular joint anterior and medial to the os acromiale.

The majority of published articles consider that the os acromiale is a risk factor for developing an impingement syndrome.