Crenel Lateral Interbody Fusion Combined With Lateral Plate Fixation for LSS Combined With Lumbar Instability

Inclusion Criteria: 1. Age 50-80 years old 2. Patients diagnosed with clinical symptoms of lumbar spinal stenosis, neurogenic intermittent claudication, the patient's walking ability is highly limited, and the quality of life is severely reduced 3. Imaging diagnosis of 1-2 LSS patients, consistent with clinical symptoms 4. Lumbar spine instability can be considered if one of the following three criteria is met: ① mechanical back pain with severe (VAS \> 7) (pain aggravates with weight bearing). Radiographs of lumbar hyperextension and flexion show a slip of at least 3mm between the two vertebrae, or a rotation Angle of 11°. ③ Degenerative slip 5. Formal conservative treatment is ineffective for more than 3 months 6. No history of lumbar surgery 7. American College of Physicians ASA Grade I or II 8. Subjects voluntarily sign informed consent as subjects Exclusion Criteria: 1. In patients with significant symptoms of lumbar radiculopathy, the pain from postural changes cannot be relieved 2. Bone stenosis, including developmental lumbar spinal stenosis 3. Free nucleus pulposus tissue into the spinal canal or cause spinal canal compression of the small joint cyst 4. Patients with hypertrophy of the yellow ligament or small joint cyst as the main pressure 5. Intervertebral space or posterior facet joints have fused 6. Infectious, traumatic and neoplastic diseases of the lumbar spine 7. Patients who are unable to undergo MRI 8. Some medical conditions, such as metabolic bone disease, autoimmune disease, poliomyelitis sequelae, osteoporosis, history of poor bone healing, and long-term oral steroids, were determined by the investigators to be unsuitable for inclusion in the study 9. Patients with evidence of neurological disorders (such as peripheral neuropathy), neuromuscular disorders (such as multiple sclerosis, Parkinson's disease, etc.), or systemic diseases (such as inflammatory arthritis) that affect bodily function 10. The patient has participated in other clinical trials in the past 3 months 11. Patients with poor adherence, judged by the researchers to be unable to complete the trial according to the study plan, such as schizophrenia and dementia, did not provide consent to volunteer to participate in the clinical study