Iatrogenic spondylolysis leading to contralateral pedicular stress fracture and unstable spondylolisthesis - A case report

Study Design. A case report of iatrogenic spondylolysis as a complication o f microdiscectomy leading to contralateral pedicular stress fracture and un stable spondylolisthesis. Objective. To improve understanding of this condition by presenting a case history and roentgenographic findings of a patient that differ from those a lready reported and to propose an effective method of surgical management. Methods. A 67-year-old woman with no history of spondylolysis or spondyloli sthesis underwent an L4-L5 microdiscectomy for a left herniated nucleus pul posus 1 year before the current consultation. For the preceding 8 months, s he had been experiencing low back and bilateral leg pain. Imaging studies r evealed a left L4 spondylolytic defect and a right L4 pedicular stress frac ture with an unstable Grade I spondylolisthesis. Results. The patient was treated with posterior spinal fusion, which result ed in complete resolution of her clinical and neurologic symptoms. Conclusions. Iatrogenic spondylolysis after microdiscectomy is an uncommon entity. However, it can lead to contralateral pedicular stress fracture and spondylolisthesis, and thus can be a source of persistent back pain after disc surgery. Surgeons caring for these patients should be aware of this po tential complication.