Delayed cerebrospinal fluid leak following lumbar interbody fusion caused by floating lamina: A case report

Rationale: Delayed cerebrospinal fluid (CSF) leakage after lumbar interbody fusion are scarce. Known causes include severe spinal canal stenosis and iatrogenic factors. This case presents a unique etiology, highlighting the importance of timely management. Prediction and prevention of postoperative complications is crucial. Patient concerns: We report a 37-year-old woman had recurrent low back pain and radiating right lower extremity pain for 2 years, which had exacerbated over the past week. Imaging revealed mild L5 spondylolisthesis, a free fragment of the L5-S1 lumbar disc, bilateral L5 pars defects (spondylolysis), and floating L5 lamina. Treatment involved L5 right laminectomy and L5-S1 lumbar interbody fusion. On postoperative day 6, the patient developed headache and bulging at the incision site. Diagnoses: Combined with analysis of the aspirated fluid, magnetic resonance imaging indications and patient’s symptoms, a diagnosis of delayed CSF leak was made. Interventions: Resection of the remaining and floating L5 left lamina and direct suturation were performed for dural tear repair followed by postoperative drainage tube placement. Outcomes: The patient was discharged with successful recovery 2 weeks after the second surgery. Follow-up lumbar magnetic resonance imaging confirmed resolution of the CSF leak and satisfactory recovery. Lessons: In lumbar pathologies with unique anatomy like a floating lamina, vigilance for delayed CSF leak is crucial. Meticulous preoperative imaging review and adaptable surgical strategies beyond conventional approaches are essential for preventing recurrence.