In Reply: We appreciate Dr. Hirsch’s comments and are pleased to expand the discussion of this important point.
He is correct in his assertion that dissection and aneurysm are distinct processes. But the goal of this review was to remind practitioners to consider the aorta as a possible source of pain when it occurs acutely or in an atypical manner.
A number of aortic processes can cause back pain, and aneurysm and dissection are two of them, aneurysm being more common than aortic dissection. But the pain can also be from aortic ulceration, aortitis, contained rupture of an aneurysm, and other more esoteric problems.
Aortic dissection often presents as a tearing, severe, thoracic back pain. Pain from a progressive abdominal aneurysm is more commonly referred to the lower back or flank and can be severe and unrelenting. It is rarely described as a tearing pain like that of dissection.
It is difficult on initial physical examination to distinguish aneurysm from dissection. The key to diagnosing aneurysm is to detect the pulsatile abdominal mass. A pulsatile, tender abdominal mass with hypotension and back pain is classically associated with rupture of an abdominal aortic aneurysm. The combination of back pain, a deficit in peripheral pulses, and hypertension is more often associated with dissection.
Without imaging and appropriate consultation, it is difficult for even an experienced provider to definitively diagnose these disorders. Without a bit of suspicion, even with a careful physical examination either disorder might be overlooked entirely, with disastrous effect. The purpose of our review was to remind the reader that these conditions, while uncommon or even rare, do occur and should be sought out in patients presenting with acute, atypical lumbar and thoracic back pain. As with each of the conditions discussed in this review, the decision to linger a bit over the patient’s history and then perform a basic, focused physical examination can be life-saving.