1. Introduction. Isthmic spondylolisthesis occurs in patients with spondylolysis 1. There is a higher incidence of L5 S spondylolisthesis than L4 5, 2 Foraminal stenosis is common in isthmic spondylolisthesis with a hypertrophic scar in the pars defect, a syndesmophyte adjacent. Most often, the results of spondylolisthesis are secondary to an anatomical defect of the pars interarticularis of the lumbar spine. the “high grade” specifier implies slippage of a vertebral body greater than that seen in 3 in people with spondylolisthesis. 1. Several etiologies can lead to HGS findings. Degenerative spondylolisthesis is the result of long-standing intersegmental instability at the lumbar motion segment. Patients with DS are typically older and may present with any combination of low back pain, neurogenic claudication, vesicorectal disorders, and radiculopathy. The etiology of DS is, whether lumbar decompression with fusion surgery is effective against degenerative spondylolisthesis of Meyerding DS is unknown. Therefore, the present study aimed to compare surgical outcomes between posterior decompression alone and posterior decompression with fusion surgery in patients with DS. Results Successful reduction of isthmic spondylolisthesis with good postoperative clinical results. Conclusion Complete uniportal endoscopic transforaminal interbody fusion is a new and . Lower grades or can be managed conservatively with exercises, and higher grades may require surgery. The grade of spondylolisthesis depends on the location of the postero-inferior corner of the vertebra. These grades are: grade I: 0-25, grade II: 26-50. level III: 51-75. grade IV: 76-100,