Ureteral injury following anterior thoracolumbar spinal instrumented fusion for adolescent idiopathic scoliosis: a case report with CT angiography analysis of surgically relevant anatomy.

Purpose: To report a rare ureteral injury following anterior spinal fusion for adolescent idiopathic scoliosis (AIS) that resulted in complete nephrectomy and to delineate the anatomical relationship between the proximal ureter and the anterior lumbar spine based on CT angiography (CTA).

Methods: Thoracolumbar spine CTAs of children with AIS were reviewed. We measured the following relationships to the ureters: lateral-most aspect of vertebral body, anterior psoas at intervertebral disc/vertebral body levels, and lateral psoas at vertebral body level. Spine level at which the renal arteries originated from the aorta was identified. Distance from origin to corresponding vertebral body/intervertebral disc also was measured.

Results: Forty-one girls and seven boys (mean age 12 years, range 7-18) were analyzed. Scoliosis lumbar convexity was left 94% and right 6%. From L1 to L4, ureter was identified within 1-2 cm of vertebral body. Distance between ureter and vertebral body and ureter and anterior psoas at intervertebral disc/vertebral body levels was less on left vs. right from L1 to L4 (p < 0.0001). Distance between ureter and lateral psoas was less on left vs. right from L1 to L2 (p = 0.0205; p = 0.0132) and greater on left vs. right from L3 to L4 (p = 0.0022; p = 0.0076). Renal artery originated at L1/L2 in > 50%. There was no difference in distance from renal artery origin to vertebral body/intervertebral disc (p = 0.4764).

Conclusion: Ureteral injury is a potentially morbid complication of anterior spine surgery. Injury can occur secondary to disrupted blood supply and mechanical tissue damage. Surgeons must clearly understand the juxta-spinal anatomy to limit dissection and modify retraction to reduce risk.

Level Of Evidence: Level IV.