Delayed Ureter Stricture and Kidney Atrophy After Oblique Lumbar Interbody Fusion

BACKGROUNDOblique lumbar interbody fusion (OLIF) is a surgical technique for lumbar interbody fusion that allows surgeons to use a large cage while preserving the spine muscles. The surgical corridor of OLIF is close to the ureter in the retroperitoneal space and therefore entails a potential for injury to this organ. Although there are some published cases of ureteral injury that were identified during OLIF, to our knowledge, there have been no reports about delayed ureteral strictures and kidney atrophy after OLIF. We report a case of ureter stricture and ipsilateral kidney atrophy that was incidentally identified a few months postoperatively without signs of ureter injury during the operation. CASE DESCRIPTIONA 49-year-old woman presented with low back and right leg pain. On lumbar magnetic resonance imaging, a Meyerding grade 1 spondylolisthesis of L4 on L5 with L4 nerve root encroachment was confirmed. The patient underwent L4/L5 OLIF and was discharged on the 10th day after surgery with improved symptoms. Three months later, an abdominopelvic computed tomography performed for an unrelated condition showed left kidney atrophy. A retrograde ureteropyelogram confirmed a stricture near the operation site. A ureter stent was successfully inserted to overcome the stricture, but renal atrophy was not reversed. CONCLUSIONSUreter injury may be observed with several months' delay after OLIF in patients without symptoms or laboratory abnormalities, even if no direct injury was noted during the procedure.