I heard there's a way to tell if I might be a good candidate for the X-stop device. It's supposed to go between two of my back bones and give me some relief from the pain caused by stenosis. Is there a way to help me decide if I should have this procedure or not?
Just as you described, the X-stop device is implanted between the spinous processes of two vertebrae. The spinous process is the bony knob you feel along your backbone. It is a projection of bone off the back of each vertebra that provides a place for ligaments and muscles to attach.
By slipping the X-stop between the spinous processes, it's a little like using a jack to lift your car off the ground. It separates the vertebrae and puts them in a slight bit of flexion -- just enough to take pressure off the spinal cord, spinal joints, and spinal nerve roots.
It's a fairly new treatment technique so research is ongoing to evaluate its effectiveness. In a recent study from Scotland, orthopedic surgeons used a positional or stand-up MRI to measure the increase in space around the spinal cord. A positional MRI takes pictures of the disc height, spinal canal area, and space around the spinal nerve roots with the patient sitting, lying down, and standing up (weight-bearing).
They found that patients who got relief from painful symptoms while in the sitting position (or with the spine flexed) were good candidates for the X-stop procedure. They also saw that patients with the most severe stenosis were the least likely to benefit from the device.
Patients are not selected for this procedure unless they have tried more conservative care such as the use of antiinflammatory medications, physical therapy, and possibly steroid injections. Talk to your surgeon about your situation -- the severity of your stenosis, the risk factors for complications, and the predictive factors for a good outcome.