Lumbar arthrodesis or fusion of the low back is one of several treatment options for spinal stenosis. Stenosis means narrowing and in this case, it means the openings for the spinal cord and spinal nerves is getting smaller.
This is a common problem in the aging, older adult. The less room there is for the nerve tissue, the more likely the chances are the person will develop painful symptoms from pressure on the nerve.
Surgery to remove the bone relieves the pressure on the nerve tissue. But it can leave the spine unstable. Fusion becomes a valuable part of the operation to hold the vertebrae in place and prevent even more problems.
Fixing the vertebral bones in place helps maintain spinal alignment and disc height. Keeping the disc spaces open helps prevent further deterioration and pressure on the spinal nerves. Without fusion, the vertebral bones may collapse putting pressure on all the soft tissue structures, including the spinal nerves.
Older patients who have osteoporosis (decreased bone mass) may need a special kind of stabilization. A less rigid device to help hold the spine may be used. At least one study from France reports using less rigid Titanium rods and screws. They had a very positive result for this type of patient.