Midline-preserving vs. midline-removing surgery for lumbar spinal stenosis: national registry study based on the Finnish spine registry (FinSpine).

Purpose: Lumbar spinal stenosis (LSS) can be treated surgically by decompressing the affected nervous structures, either by removing or preserving the midline structures. There is no conclusive evidence demonstrating the superiority of either surgical technique in the treatment of LSS. Our purpose was to compare the posterior midline-preserving techniques with midline-removing techniques separately for central stenosis and lateral recess stenosis to evaluate whether either technique leads to superior postoperative results in terms of functional outcome or pain reduction, by using data from the Finnish Spine Registry (FinSpine).