Introduction: Evaluating the effectiveness as well the feasibility of applying DIAM into treating lumbar spinal stenosis. Material and method: 30 patients have been diagnosed and received surgical treatment of lumbar spinal stenosis with DIAM in Viet Duc hospital from February, 2011 to July, 2011. Prospective cohort, cross-sectional study. Results: Assessing treatment results after 6 months. Reliving back and leg pain via VAS: back: from 5.7 + or - 1.24 to 1.1 + or - 0.69
leg: from 6.2 + or - 1.7 to 1.0 + or - 0.74 (P 0.001). ODI: from 48.3 + or - 15.39 ( percent) to 22.4 + or - 7.60 ( percent) (p0.001). Macnab: very good and good ( 86.7 percent). Disc mean height: from 16.6 + or - 1.19 to 17.5 + or - 1.21 (mm), foraminal mean height: from 20.9 + or - 1.50 to 23.1 + or - 1.42 (mm). Operation time: 54.0 + or - 13.11 mins, no blood transfusion within and after the operation. Complication: Dural tear 2 cases. No other severe complication. Conclusion: Applying DIAM in treating lumbar spinal stenosis is safe, feasible, and has initially proven its high effectiveness.