The occurrence of vascular displacement into intervertebral disc space following the compensated sagittal imbalance of the spine: a case report and review of literature.

Background: It is known that sagittal compensating mechanisms are created for counteracting sagittal imbalance problems; however, they can sometimes be associated with incidents which affect the plan of management.
Purpose: The purpose of this study was to report a case of the occurrence of common iliac vessel displacement into the intervertebral disc space following one of the spinal compensatory mechanisms.
Material and Methods: The authors demonstrated this case by showing the patient history, physical examination, imaging studies, and treatment strategy as well as by reviewing some related literature.
Results: An 81-year-old woman presented with a long history of low back pain with claudication. An upright plain radiograph and flexion-extension study demonstrated a progressive local thoracolumbar kyphosis and losing of lumbar lordosis with significant widening of the intervertebral disc space of L4-L5. An MRI scan and 3D volume rendering spiral computed tomography (3D-CT) revealed an abnormal content which was depicted as common iliac vessels inside the disc space of L4-L5. Consequently, a rare case of the occurrence of common iliac vessel displacement into the intervertebral disc space following one of the spinal compensatory mechanisms was reported.
Conclusion: The occurrence of vascular displacement into the intervertebral disc space related to lumbar hyperextension, as a compensating mechanism, is a rare incident but can occur. Consequently, when this mechanism presents with abnormal widening of the intervertebral disc space, especially at the low lumbar level, it should raise surgeon's concern about the probability of vascular injury when performing a disc procedure. Thorough investigation with imaging studies and selecting the optimum surgical treatment are warranted.