Morphometric analysis of significant vascular structures in posterior disc surgery with computed tomography angiography.

BACKGROUND: Vascular injuries, which are rarely seen in all spinal area procedures, especially lumbar disc surgery, are vitally important. The relationship between the course of the iliac artery and vein and intervertebral disc distance was studied morphometrically in patients who had undergone computed tomography angiography for abdominal aorta.

METHODS: This study was carried out retrospectively. A total of 100 patients who had undergone computed tomography angiography participated in the study. The aorta bifurcation, right and left common iliac artery (R/LCIA) and vein (R/LCIV), and the location of the common iliac artery bifurcation were investigated. The location of these vascular structures at the level of the spinal vertebral body and at the intervertebral disc level, determination of a fat plane between them, and the anterior longitudinal ligament (ALL) were analyzed.

RESULTS: At the L4-5 intertransversarius dorsalis (IDL), the RCIV was determined to be at the 12 o'clock position RCIA in 51% of cases and between the ratio of 67% ALL. The LCIA was at the 1 o'clock position in 72% and adjacent to the ALL in 47%. The RCIV was located in the 11 o'clock position and there was no fat plane between the RCIV and the ALL in 92%. In 80%, the LCIV was located at the 11-12 o'clock position and in 18% transversely along the 12-1-2 o'clock region. There was no fat plane between the LCIV and the ALL in any patient. At the L5-S1 IDL, the RCIA was observed at the 10 o'clock position in 63%, and there was no fat plane between the RCIA and the ALL. The LCIA was at the 2 o'clock position in 72% and the LCIV was between the ALL and the LCIA in 92%. The RCIV was located at the 9-10 o'clock position in 95% and no fat plane was found between the ALL and the RCIV in 60%. The LCIV was located at the 1-2 o'clock position in 96% and there was no fat plane between the LCIV and the ALL in 92%; it was located close to the ALL.

CONCLUSION: The L4-5 IDL RCIA was located at the midline and at a 30° angle position. The LCIV was located between them. The L5-S1 IDL located at LCIA left at 60° position was quite close to ALL with LCIV. When the distance from the ALL was compared and the frequency of fat planes between the ALL and the CIAs are considered, it can be noted that the RCIA in the L4-L5 IDL (p<0.001) and the LCIA in the L5-S1 IDL (p<0.001) were located remotely and in a more protected position. It should be kept in mind that the LCIV can progress along the L4-5 ID level, adjacent to the ALL, as well as transversely.