Degenerative spine disorders are very common in the aging population. Degenerative spondylolisthesis is a relatively uncommon cause of chronic back pain in these patients. We present a case of high-grade spondylolisthesis managed with posterior lumbar interbody fusion (PLIF) and reduction of the listhesis with excellent results. A 56-year-old woman presented with chronic lower back pain managed as an outpatient for over 5 months with no relief. She had no history of trauma or risk factors for malignancy. Lumbosacral CT showed Meyerding grade 3 anterolisthesis of the fifth lumbar vertebra with complete L5-S1 disc collapse and bilateral spondylolysis. An MRI confirmed the findings. There was no spinal canal stenosis. The patient was managed with L4-L5-S1 transpedicular fixation and L5-S1 interbody cage with reduction of the listhesis. The patient had an incidental intraoperative dural tear which was repaired primarily and a wound drain was kept for 5 days without complications. The patient was ambulating by day 5 and was discharged without complications on day 10. Degenerative spondylolisthesis can cause chronic back pain with or without a history of trauma. Although no specific clinical features exist for this condition, it should be suspected in elderly patients even in the absence of a history of trauma. Surgical management in high-grade spondylolisthesis is indicated with interbody fixation and reduction.