Indirect decompression of the central lumbar spinal canal by means of simultaneous bilateral transforaminal lumbar interbody fusion for severe degenerative lumbar canal stenosis with 3 years minimum follow-up

•Indirect decompression of the lumbar canal in degenerative lumbar canal stenosis (LCS) with instability shows potential to decrease surgical invasion and eliminate the risk of dural tear and nerve injury.•Severe stenosis is considered a contraindication for indirect decompression because of the risk of insufficient decompression and restenosis in case of cage sinking.•Removing both facet joints and bilateral distraction allow for sufficient indirect decompression by ligamentotaxis; inserting multiple cages from both sides spreads the weight bearing area to prevent restenosis due to cage sinking.•Bilateral transforaminal lumbar interbody fusion (TLIF) with ligamentum flavum preservation allows for successful indirect decompression in cases who have contraindications to indirect decompression through anterior approaches or conventional TLIF.