In this study, neurosurgeons from Italy evaluate the results of unilateral spinal decompression. Unilateral means the operation was done from one side.
The patients all had spinal stenosis with back and leg pain that limited walking. Stenosis is a narrowing of the spinal canal. Pressure on the spinal cord and spinal nerves is the cause of the painful symptoms and limited function.
Everyone in the study had conservative care without surgery first. The results were not satisfactory and surgery was needed. The operation was described in detail in this report. Only one surgeon did the surgeries. A special surgical microscope was used. The surgeon had a clear view of all the anatomic structures.
First, part of the lamina (bone around the spinal canal) was removed to take pressure off the neural structures. The procedure is called a laminotomy. A special microdrill was used to thin the laminae into a V-shape.
This made it possible to remove the right amount of bone without causing a collapse of the remaining bone. Since the surgeon used a microscope, the procedure is also referred to as a microdecompression.
A thickened ligament called the ligamentum flavum (LF) was removed at the level of the stenosis. The rest of the LF was left in place to help protect the sac around the spinal cord. Any overgrowth of bone or bone spurs around the facet (spinal) joints was shaved away. Some patients only had one level decompressed. Others had microdecompression of two or three levels.
The surgeons were able to repeat these steps on the other side of the spine. This was done from the original side and without making a second incision. They were able to reach the opposite side of the spine by raising and tilting the table. This made it possible to change the angle of the microscope to reach across.
The authors note that the posterior facet joints, ligaments, and other structures are not affected. This means the patients didn’t need a spinal fusion at the same time the decompression was done.
Results were measured by pain levels, change in function, and imaging studies (X-rays and CT scans). Almost 90 per cent had improvement in pain and walking. Some patients reported still having sensory or motor loss. The stenosis did not return in any of the patients.
The authors conclude that unilateral microdecompression of spinal stenosis is safe and effective for all ages. It can be used to achieve bilateral (both sides) decompression. It is especially useful when there are natural anatomic changes in the shape of the bone that contribute to the stenosis.