The operation releases compression and pressure from a disc or ligament or bony structure compressing a nerve or the spinal cord. It can involve a laminectomy, discectomy and/or spinal fusion. Lumbar decompression is often used to treat : 1. Spinal stenosis -narrowing of a section of the spinal column due to degenerative disc bulge combined with overgrowth of bone such as facet joints or as a results of thickening of the ligamentum flavum, and leads to a compression of the dural sac and spinal nerves. 2. Slipped disc with persistent sciatica symptoms - where a damaged spinal disc presses down on an underlying nerve . 3. Spinal injury - such as a fracture or swelling of the tissue 4. Metastatic spinal cord compression - where cancer spreads into the spine and presses on the spinal cord or nerves.