Spinal stenosis can be addressed either microsurgically or in a traditional manner depending on the number of levels affected. The basis for any microsurgical procedure is the use of magnification and bright illumination of the operative field. This can be provided to a satisfactory degree by use of an operative microscope, operative magnifying loupes, and fiberoptic head lamp. The primary advantage of microsurgery is a reduction of tissue trauma, a decrease in operative recovery, and a reduction of postsurgical scarring and operative trauma. Microsurgery can be performed at one or more levels, either unilaterally (one side), or bilaterally (both sides). Obviously, the primary benefits diminish as the number of levels increase due to the exposure necessary to address each level.

The basic one level laminectomy for lateral recess stenosis in the lumbar spine is performed as follows. An approximately 1 inch or less incision is made, overlying the disc space in the skin as determined by an intraoperative x-ray. The fatty tissue beneath the skin is then divided to the dorsal fascia which is the thick tissue overlying the muscle above the spine. This fascia is then incised and the musculature swept to the side revealing the underlying bone and ligaments. The spinal canal is entered by resection of the ligamentum flavum which is the ligament connecting between the lamina of each vertebra. The lamina are the flat areas of bone overlying the top of the canal at each level. A portion of the edge of the lamina above and below is resected with the ligaments to allow adequate exposure of the underlying nerve root. Once the canal has been exposed, the nerve root is identified and gently moved to the center of the canal and held with a retractor. Small veins are coagulated to minimize bleeding. The medial edge of the facet joint is removed until the nerve is adequately relieved of any pressure. The foramen can be enlarged by removing the upper portion of the superior facet. When stenosis is also present centrally the lamina may be removed completely on both sides, including the spinous process, along the area of narrowing. A small piece of fat is usually placed over the surface of the nerve to prevent adhesions. More recently, a number of synthetic materials have been made available which provide this same function. The tissues are then closed in three layers, the muscle fascia, the subcutaneous fat, and the skin. Most frequently, the skin is closed under its surface using a subcuticular suture.