Laminectomy is the surgical removal of the lamina, the portion of the vertebral bone that projects around the back of the spine protecting the spinal cord and nerves as they pass through the spinal canal. The lamina overlap one another much like shingles on a tile roof. A laminectomy is usually performed when there is a compressive lesion on the spinal cord or nerve roots that must be relieved or there is some other condition that requires access to the neurologic structures. The laminectomy is akin to “taking the roof off” to relieve pressure and most commonly performed for spinal stenosis. Newer MISS techniques allow laminectomy to be performed as an outpatient procedure in some cases.
Who is a candidate for Laminectomy?
The most common indication for laminectomy is arthritis that produces thickened ligaments, disc protrusions, and enlarged facet joints that compress the nerves and spinal cord producing spinal stenosis. This is most common in the neck and lumbar spine where most spinal motion occurs and less common in the midback (thoracic spine) as the ribs limit motion. Most patients with spinal stenosis are treated non operatively and those with neurologic injury or who fail to improve with non operative treatment might be candidates for surgical treatment. Patients with instability or underlying deformity (kyphosis, scoliosis, spondylolisthesis) may also require a stabilization procedure with fusion and instrumentation.
What is involved in Laminectomy?
A laminectomy requires a posterior approach to the spine. The paraspinal muscles are retracted off the posterior elements and the ligamentum flavum connecting the lower lamina of the upper vertebra to the upper lamina of the lower vertebra is resected with Kerrison rongeurs. The lamina is then resected with a combination of a high speed burr and rongeurs.
Figure 1. Illustration demonstrating resection of the L4 lamina and partial laminotomy with kerrison at the left L3 level.
Portions of the facet joints may be removed (medial facetectomy) to provide access and decompression of the nerve roots as they exit the spine through the foramen (foraminotomy).
What are the pros and cons of Laminectomy?
All surgical procedures have inherent risks. These include but are not limited to infection, dural tear, nerve injury, instability, and chronic pain. Each patient is unique and only a comprehensive evaluation with a fellowship trained spine surgeon can give you the best appreciation of the risks and benefits for surgical treatment of your condition.