MIS-D Versus MIS-TLIF for the Treatment of Lumbar Spinal Stenosis

Inclusion Criteria: * Intermittent claudication with pain or numbness or weakness of lower limb(s) with or without low back pain * An imaging study (MRI or CT) showing single level lumbar spinal stenosis Exclusion Criteria: * Insufficient conservative treatment (6 weeks) * Cauda equina syndrome or progressive neurologic deficit requiring urgent surgical intervention * Previous spinal surgery * Other comorbid conditions that contraindicating surgery * Possible pregnancy that contraindicating radiological examination * Age less than 18 years old * Combination with 2°spondylolisthesis or segmental instability (slip distance \>4mm or angle change \>10° in dynamic plain film) * Combination with other spinal disorder requiring advanced surgery (such as lumbar stenosis, spondylolisthesis, deformity, fracture, infection, tumor and so on) * Equal to or more than two responsible level