BACKGROUND : Minimally invasive endoscopic spine surgery is useful for the treatment for various spinal conditions. While surgery-related complications such as dural injury, exiting nerve root injury, incomplete decompression, and hematoma have been reported, there are few reports of late complications following endoscopic surgery. METHODS : A 51-year-old male complained of radiating pain to the right leg. The patient underwent endoscopic foraminal decompression under the diagnosis of foraminal stenosis with isthmic type spondylolisthesis (L5/S1). The lower extremity radiating pain was improved after surgery. 6 weeks after surgery, the patient's symptoms recurred. The patient experienced a sudden onset of severe low back pain, which was aggravated by any motion of the lumbar spine. CT and MRI revealed a fracture line with a sclerotic margin at the base of the right pedicle at the L5 level. Since the symptoms significantly interfered with his normal activities of daily living, the patient was treated with a total laminectomy, followed by posterior instrumented fusion DESCRIPTION: As the indication for endoscopic spinal surgery is widening, endoscopic decompression surgery is being performed for patients with low grade lumbar spondylolisthesis, regardless of the presence of advanced spinal instability. However, endoscopic decompression surgery may cause damage to the posterior facet joint, which may have worsened the instability and lead to late complications such as progression of spondylolisthesis and pedicle stress fracture. CONCLUSIONS : The surgeon should carefully review risk factors such as isthmic type spondylolisthesis before planning the spine surgery and minimize facet joint damage during endoscopic decompression.