Insidious intraoperative ureteral injury as a complication in oblique lumbar interbody fusion surgery: a case report

BACKGROUND: Oblique lumbar interbody fusion surgery is a recently introduced minimally invasive lateral interbody fusion surgery for degenerative lumbar disease. There have been no reports of associated ureteral injury. CASE PRESENTATION: A 77-year-old Japanese woman underwent oblique lumbar interbody fusion surgery for lumbar spondylolisthesis with refractory low back pain and pain in both legs. The patient experienced abdominal pain 2 days after surgery. Delayed contrast-enhanced computed tomography and retrograde urography revealed leakage of contrasted urine from the ureter into the retroperitoneal space, indicating a ureteral injury. Immediate percutaneous nephrostomy was performed to recover her condition, followed by additional ureteral stenting. She is now free from preoperative symptoms but requires periodic changing of the ureteral stent, with no urinary symptoms. CONCLUSION: The current report described a rare but possible case of ureteral injury following oblique lumbar interbody fusion surgery. Iatrogenic ureteral injury, as reported in the current case, is uncommon following oblique lumbar interbody fusion surgery, and the injury may have been caused by a procedural error. Considering the findings from urological examinations, we speculate that the thread pin that fixates the retractor injured the ureter during its installation. This case highlights the importance of careful attention while exposing the retroperitoneal space to avoid minor organs, including the ureters, as well as major organs. Ureteral injuries should ideally be detected and diagnosed as soon as possible by careful physical and radiological examinations, such as with delayed contrast-enhanced computed tomography and retrograde urography, to salvage the injured nephroureteral system. The current report also highlights that careful use of surgical instruments is key for preventing intraoperative complications, including ureteral injury.