Back Pain numbness in legs and arms. MRI Results

I am 28 years old 6'0" 195 lbs. I have had back pain for a bunch of years, but this year it seems to be getting more consistent and also i have had problems with leg numbness and pain and ocassional arm numbness and pain. And even the ocassional numbess in my face. also recently i have been experiencing muscles around my knees twitching. I went for an MRI in october and the ortho sent me to a pain management place for cortisone injections. i just got the 3rd of the three about 2 weeks ago. I am feeling much of a difference. i want to say its helped, but i just don't feel like it has. i want to explore other options, but i want to get some opions before i go back to the doc and tell him/her the cortisone hasn't solved anything.

The details of my MRI Results are as follows:

10/24/2011:MRI LUMBAR SPINE WIO CONTRAST
MRI of the lumbar spine was performed in sagittal T1, T2 and axial T2 and proton density images. There is no prior similar study at this center for comparison.
There is preservation of the normal lumbar lordosis without compression fracture or spondylolisthesis. The conus medullaris terminates in normal position at the T12-Ll leveI. There is no cauda equina nerve root clumping to suggest arachnoiditis.
The Ll-2 and L2-3 levels show no disk herniation, significant canal or neural foraminal stenosis.
At L3-4, there is a moderate central disk herniation causing mild canal stenosis and mild bilateral neural foraminal stenosis.
At L4-5 there is a moderate central disk herniation with an annular tear of the posterior margin of the disk. Mild ligamentum flavum hypertrophy is seen at this level. Findings cause moderate bilateral neural foraminal stenosis.
At L5-S1, there is a moderate central disk herniation and mild bilateral neural foraminal stenosis.
The vertebral body marrow signal is normal. Incidental note is made of a small Schmorl's node at the superior
end plate of LI. No paraspinous soft tissue mass is seen.
IMPRESSION: Disk herniations levels L3-4, L4-5 and L5-S1 as described.