Can a Lumbosacral plexus injury resolve after an extended period of time?

After a suicide attempt I laid on the floor for a number of hours before being found.  When I awoke in the hospital I had no use of my left leg or foot.  The injury was literally ignored for three days in the hospital while they were dealing with my rhabdomyolysis and kidney failure.  I was experiencing severe pain in the leg and foot at the time but nothing was done.  They told me I shouldn't be having pain in the leg.  
After numerous CT scans and MRI's I was told I had peroneal nerve damage and it would resolve.  It never did.  Nothing showed on the CT scans of MRI.  Apparently they didn't know for sure.
I have seen other neurologists and doctors and no one can see anything on the MRI to account for their diagnosis.
It is now two years later and I still have nerve damage in the leg.  The pain is resolving and only is present intermitantly.  I have regained minimal movement in the foot.  Some dorsifexion, more plantar flexion and minimal movement of the toes, which was totally absent until 3 months ago.  Yet, I still have foot drop, wear a brace and need a cane to ambulate most of the time.  
Not one physician has ever done an MRI or CT of my head, only my hips, spine and leg.  Could there be an underlying head injury related to this neuropathy?  Is there anyone out there doing studies that I might be interested in?  Everything I find related to Lumbosacralplexus injury usually show major trauma to that area of the body.  I had no injury to my spine, hips, or legs.  I had no cuts, scrapes, hematomas etc.  
I have been told that any hope for resolution of this condition was gone after 2 years.  Is this true?