I had back surgery in december, lumbar decompression with laminectiomy at the l4-l5 level. With microdisectomy. Last MRI still shows at posterior disc bulge at the same level. I am still experiencing severe episodes of burning pain down in my lower extre

See specialist. You may be having continued pain due to recurrent stenosis or epidural fibrosis/scar after the procedure. You may benefit from some injections to help alleviate any post-operative inflammation.
May have instability. One reason why you may not be getting better: presence of instability at L4-5. Have you had standing Xrays of the lower back? If not, then ask your MD for Standing Xrays of lumbar spine including flexion (bending forward) and extension (bending backward) views. Many patients with instability feel shifting of the spine with bending + pain also changes with position: typically better when lie down.
Refered pain-tear. Unfortunately, you have 'failed back syndrome'-means surgery failed to resolve issue.I suggest consulting a good osteopathic manipulative medicine dr to determine the actual cause.Could be anything from a remaining minor disc tear to injury to a ligament to vertebral dysf.Md's assume a disc bulge or hernia are always the cause, but there are other causes, some easily fixed via manip or prolotherapy.