There are different techniques when performing an operation for spinal stenosis. Expected outcomes from all methods are very similar and the best choice of operation will be decided after discussion with Mr Paremain.
Laminectomy and/or laminotomy
This is performed through an incision in the midline of the lower back. The position and length of incision is determined by which levels of the spine and how many nerves are involved. The muscles are then held apart to gain access to the bony arch and roof of the spine (lamina). Next, the surgeon needs to gain entry into the spinal canal by removing some bone, either by cutting away the whole area of lamina (laminectomy) or making a small window in the lamina (laminotomy) with a high-speed burr (like a dentist’s drill) or an osteotome. Further bone and ligament are then removed and often the facet joints, which are directly over the nerve roots, are undercut (trimmed) to relieve the pressure on the nerves and give them a wider passage as they pass out of the spine.
The illustration below shows the ligamentum flavum has been removed to expose the contents of the spinal canal. The flavum forms part of the roof of the spinal canal and removing it allows the canal contents to expand. This in turn relieves the pressure on the nerves running within the canal.