The addendum I received from the neurosurgeon said significant HNP at L5-S1, for which he recommends I lose weight and go through pain management. I have lost 14 pounds and would like to lose another 40 which puts me at my optimal weight. The weight loss so far has not lessened the pain, but I realize I still have more to lose.I called his office after receiving your reply and the nurse said S1 means the same as SI. She also said the Dr's dictation says I have radiculopathy, although his addendum only says "CT scan of the lumbar spine reveals an annular bulge at L-4-5 that is small and L5-S1 showing a radial disc buldge, narrowing the inferior aspect of both neural foramma, but notcompromising the nerve root."

Does that make sense? Can I have radiculopathy without the disc bulge touching the nerve root?

Nothing in his notes mentions the femoral cutaneous nerve.

Yes, disc bulges can cause radiculopathy without touching the nerve root on MRI. A standard MRI is what your back looks like while lying flat in a tube for an hour, we don't really know what it looks like as you sit, move, etc... A diagnostic work-up by an interventional pain medicine doctor could help decide which is causing your pain. This would involve numbing up the two structures (the S1 nerve root and the SI joint) and seeing which procedure gives you relief of most of your pain. SI and S1 are not the same thing. S1 is a low back spinal nerve and SI (or short for sacroiliac) is a joint in your pelvis.

Christopher J. Centeno, M.D.