A laminectomy involves the removal of part or all of the bone covering the spinal canal. The purpose of this procedure can be to free nerve roots, remove a tumor, bone spur or to perform certain types of fusion procedures.
Removing the lamina (laminectomy) is much like removing the cover on a fuse box to access the wiring. By removing the lamina, the surgeon gains access to the disc area and frees more space for the nerves inside.
During the surgery, a one to two-inch incision is made in the low back. The spine surgeon then chips away the lamina of one or more vertebrae to gain access to the disc area. The surgeon will then remove any fragments that may have broken away from the disc, as well as the area of disc that is herniated and pressuring a nerve root. The entire disc is not removed. If it was, you would lose the shock-absorbing function of the disc between the vertebrae. Instead, the surgeon typically removes the part of the disc that has ruptured outward, along with another 10 or 20 percent of the disc, in order to prevent future problems from arising.
A laminectomy is often used to treat recurrent disc herniations, or where scar tissue is involved. Laminectomy may also be used in cases of spinal stenosis in which the entire canal is narrowed like a ring on a swollen finger.