A Technique for the Dynamical Evaluation of the Acromiohumeral Distance of the Shoulder in the Seated Position Under Open-Field MRI

Introduction Nowadays, the current understanding is that the shoulder impingement syndrome (SIS) is characterized by impairment and dysfunction of several structures, contained in the subacromial space, which alter normal shoulder movements of flexion and abduction and provoke pain. Currently, the SIS is a clinical diagnosis based on the patient’s history and physical findings which occurs at about 90 degrees of forward flexion and abduction of the arm. Unfortunately, with normal configuration MRI, only indirect signs of this condition can be described [1,2] due to the fact that the examination can not be performed with the patient in the position in which the SIS occurs.