Drs Iyengar and Nottage are from The Sports Clinic Orthopaedic Medical Associates, Inc, Laguna Hills, and Dr Burnett is from Laguna Niguel MRI, Inc, Laguna Niguel, California.
Drs Iyengar, Burnett, and Nottage have no relevant financial relationships to disclose.
The authors thank Arif Ali, MD, Eric M. Price, MD, Gen Marayama, MD, and Anthony Stauffer, MD, for their preliminary work on this article, and Phil Pador, MRI technician, for his assistance in providing the images for the article.
Correspondence should be addressed to: Keith R. Burnett, MD, Laguna Niguel MRI, Inc, 25500 Rancho Niguel Rd, Ste 140, Laguna Niguel, CA 92677 (firstname.lastname@example.org).
Shoulder magnetic resonance imaging (MRI) is the gold standard imaging modality for evaluating soft tissue in the shoulder joint. The abduction external rotation (ABER) view has been discussed in the literature as an excellent tool beyond the conventional 3 sequences (coronal, sagittal, and axial) for accurately assessing anteroinferior labral detachment and both partial- and full-thickness tears of the rotator cuff tendons.1–5 Placing the arm in an abducted and externally rotated position tensions the anteroinferior glenohumeral ligament and labrum. If a labral detachment is present, contrast solution defines the defect. Likewise, abduction and external rotation of the arm releases tension on the cuff relative to the normal coronal view obtained with the arm in adduction. As a result, subtle articularsided partial thickness flap tears will not lie apposed to the adjacent intact fibers of the remaining rotator cuff nor be effaced against the humeral head, and intra-articular or intravenous contrast can enhance visualization of the tear.6 In addition, tears with a horizontal component are identified and characterized with increased sensitivity with the ABER view.4
The ABER view is a modified axial view. Because the orientation of the ABER view differs from the traditional images that orthopedists are accustomed to viewing, its interpretation can be confusing for those with limited or no experience. Furthermore, the execution of the ABER view can be a challenge for the technologist unfamiliar with its use. This article addresses the method by which the ABER technique is performed and the regional anatomy that can be seen on these MRI scans.
Orthopedists consider 90° of abduction and 90° of external rotation the position of apprehension. However, most conventional bore-style MRI scanners do not allow for the shoulder to be placed in this position. The narrow confines of a closed tube usually necessitate use of the more commonly performed position for the ABER view with the arm abducted and the hand tucked beneath the patient’s head, so as to lessen the mediolateral dimension of the patient’s upper torso (Figure 1).
Despite the clear diagnostic advantages of the ABER sequence, adoption has not been ubiquitous.8,9 This fact is confirmed by the informal polling of our sports medicine fellows and the attendees and faculty at a yearly international conference exclusively devoted to shoulder surgery (K. Burnett, oral communication, 2005–2008). While the issue has not been systematically investigated, we postulate several responsible factors. Adding the sequence prolongs examination time by approximately 25% (including positioning), potentially detracting from time available to other patient needs and decreasing efficient use of limited scanner resources.
Also, the ABER positioning is uncomfortable for some patients and can detract from the patient’s perception of the testing experience. For a few patients, typically those with a history of multiple shoulder dislocations, the positioning itself may be intolerable due to apprehension. Nevertheless, the ABER noncompliance rate for all MRI remains low, but is likely between 1% and 3% (K. Burnett, oral communication, 2003–2009). Busy departments may not wish to add time to their scans, and low-volume facilities may…