@thoracic Thank you for sharing that information on the X -stop implant. I was curious about how it works, so I looked and found this. Basically, it prevents the vertebrae from moving closer to each other by holding then fixed in place on the outside of the spine so the nerve roots don't get compressed which are between the vertebrae. It looks like it could also prevent the slipping of vertebrae past each other (because they are fixed together) which is another reason that a spinal canal can become narrowed. A definitive answer needs to come from a doctor on if this is right for a particular patient.
https://journals.lww.com/neurotodayonline/Fulltext/2007/08210/New_Device_for_Relief_of_Lumbar_Spinal_Stenosis.3.aspx