Laminectomy
A one inch (or longer for extensive stenosis) incision is made in the middle of the back over the effected region of the spine. The muscles over the bone are moved aside until the laminae are visualized. The correct level is then identified again. With the use of a microscope and specialized tools, the laminae are removed and the nerves are decompressed (released so that they are no longer pinched). All the unnecessary bone spurs and thickened ligaments that compress the nerves are also removed. This portion of the case is called a laminectomy and is all that is required in the majority of cases of spinal stenosis. This is a very safe operation which is usually performed in a short period of time (30 minutes to 120 minutes depending of the extent of stenosis) without any significant complications (I will discuss individual complications with you). The overwhelming majority of patients with spinal stenosis experience immediate relief of their symptoms after surgery and are very satisfied.
Laminectomy with Fusion
Patients with back pain due to spondylolisthesis (abnormally slippage between bones), scoliosis (curvature of the spine) or spondylosis (severe arthritis of the spine) may require a fusion with or without the placement of screws and rods. While this is also a very safe procedure, it does add more operative time and is generally associated with a slightly longer recovery and postoperative pain compared to laminectomy alone. After this procedure, most people go home in 3-4 days.

Figure: Lateral radiograph (Xray) demonstrating a spondylolisthesis (slipping of the bones) at L4-5

Figure: X-rays of the same patient after he underwent a L4-5 laminectomy & fusion to stabilize the slip at L4-5. The screws and rods prevent the abnormal motion (translation) between the L4 and L5 bones thus relieving the pain.