Explain long term effect of pinched nerves near L4-L5, L5-S1

I am 41 years old, male
My MRI description Date 07-11-2008
Five lumbarized non-rib-bearing segments are assumed.

Sagittal alignment is normal.  Degenerative disc disease seen at L3-4, L4-5 and L5-S1.  Degenerative narrowing, disc dehydration, and posterior circumferential annular bulging seen at each level.

Note also made of right paracentral posterior disc protrusion ant L3-4 with caudal extension.  Extrusion measures about 5mm in width and depth.   It measures almost 1cm in greatest length.  It produces mass effect upon the theacal sac and proximal right L4 root in subarticular/lateral recess.

Axial scans at L4-5 indicate posterior radial annular tear or fissure.  Degenerative annular bulging present.  No disc protrusion or extrusion seen.  Anterior border thecal sac is flat in the bibulging annulus.

Axial scans at L5-S1 indicate broad based shallow left paracentral posterior disc protrusion.  This produces slight mass effect upon and displacement of proximal left S1 root which is not enlarged.

Multilevel mild facet arthropathy identified.  No significant forminal narrowing seen.  No central canal stenosis identified.  Unremarkable conus located at T12-L1  Bone marrow signal is normal.

*** Impression
1. Degenerative disc disease at L3-4, L4-5, L5-S1
2. Right paracentral posterior disc extrusion with caudal extension at L3-4 impinging upon proximal right L4 root.
3. Shallow broad based left paracentral posterior disc protrusion at L5-S1 minimally impinging upon proximal S1 root.

After receiving two cortizone injections directly in the effected are, my pain is gone.  I am noticing that my right foot is sometimes not responding as quickly as it used to.  Occasionally I stumble, and might loose my footing. (very occasionally).

My question is?
1.Long term effect of pinched nerve roots.
I know I need to see a specialist.
2. Which is the better approach? Neurologist or Ortho.  I have already seen an Ortho, hence the cortizone injections.
3. If I don't have pain anymore, and the pain comes back.  I cortizone just delaying the possible better results of surgery?
Any resources would be greatly appreciated.

This injury spawns back from an injury in my early 20's