Introduction: LCS is defined as a narrowing of any part of the lumbar spinal canal. Several surgical techniques for lumbar spine decompression have been described over the last few decades. The aim of surgery for symptomatic LCS is to relieve the symptoms by adequate neural decompression while preserving of the anatomy and the biomechanical function of the lumbar spine as much as possible.

Methods: Prospective study was conducted from September 2015 to August 2017 including two groups. Group A treated with conventional laminectomy without fusion. Group B treated with unilateral laminectomy with bilateral decompression. We used Oswestry Disability Index to assess pre and postoperative disabilities and pain.

Results: : In this study, statistical results revealed that there was statistically significant in the improvement of claudicating sciatica between the two groups regarding the Oswestry disability index (p-value<0.001). There was statistical significance between two groups regarding blood loss (p-value<0.001), length of surgical procedure (p-value=0.009), postoperative hospital stays (p-value<0.001) and postoperative complication.

Conclusions: Based on short-term follow-up, a minimally invasive technique like ULBD allowed decompression preserving spine stability with a natural range of motion, with less blood loss, less hospital stay and decreased intraoperative and postoperative complication rather than conventional laminectomy without fusion.

Patient Care: at the end of my research , we found that minimal invasive procedure like ULBD is a very good choice for patients with less blood loss, less backpain and rapid return to work we could do that procedure in our small university with our leica f50 microscope , so we helped a lot of patients .

Learning Objectives: To evaluate the results of different methods of decompression in Lumbar canal stenosis regarding the effectiveness of different techniques in relieving symptoms, duration of surgery, intraoperative blood loss, and decreasing of postoperative complications.

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