Lumbar Spine surgery is performed in the lumbar spine or lower back.
The lumbar spine is also known as low back. It consists of 5 vertebrae numbered from L1 to L5. These vertebrae (vertebral bodies) are the largest in the spine and support the head and trunk. For example, the L5 vertebra transfers upper body weight through the sacrum and pelvis into the legs. The sacrum consists of 5 naturally fused vertebrae and provides a stable platform for the spinal column. Although the bones of sacrum are fused, they are numbered S1 through S5. The pelvis is often referred to as the hip.
Between each vertebral body is a disc. Discs are numbered according to their spinal position. For example, the L4-L5 disc is found between the 4th and 5th lumbar vertebrae. The low back discs are the spine’s largest. The discs match the kidney-shape of the vertebrae. There are 2 parts to each disc. The outer layer consists of rings of tough, yet flexible cartilage called the annulus fibrosus. Inside the annulus is a jelly-like substance called the nucleus pulposus. The nucleus contains mostly water to help maintain hydrostatic disc pressure (balance).
• Disc act as a spinal shock absorber between the vertebral bodies. Their main function is to reduce friction between two bones, so that bones are unaffected.
• Disc functions as a flexible pivots which helps to do a smooth movement between two vertebrae.
The lumbar discs are very tough in nature. The deep injuries due to an accident can cause wear and tear of the discs, so that disc gets break down and lead to low back osteoarthritis. In the spine, osteoarthritis is called Spondylosis. It is essentially the same degenerative process that leads to arthritis of the hip and knee joints. The degenerative process can lead to significant changes in the lumbar spine anatomy.
• Internal disruption of the intervertebral disc
• Abnormal motion of the vertebrae
• Compression of the cauda equina and/or nerve
Lumbar decompression procedures are generally performed from the posterior (back) and include the following techniques:
When disc material and/or bone spurs press against a nerve exiting the foramen (nerve passageway), a foraminotomy may be performed. Otomy is the medical term for making an opening. A foraminotomy makes the opening of the foramen larger and relieves nerve compression.
To access disc material invading the spinal canal, a small opening is made in the lamina. A laminotomy is generally performed during a lumbar Minimal Access Spine Technology (MAST) procedure.
Laminectomy includes complete or partial removal of Lamina. A Laminectomy is performed to relieve spinal cord compression or to gain access to a disc from the back. Laminectomy is often used to treat lumbar stenosis, a narrowing of the spinal canal sometimes caused by arthritis.
Facetectomy involves a complete or partial removal of the facet joint. A facetectomy is performed to reduce nerve root compression or to gain access to disc space.
It includes Surgical removal of all or part of a disc. Discectomy can be performed from the posterior (back) or front (anterior) through the abdominal cavity to reach the spine.