Femoral Neuropathy after Knee Surgery

I have had numerous knee surgeries but this past June I had an athroscopy to determine the cause of on going knee pain.  Prior to the surgery I had a femoral nerve block.  The surgery found small bone chips as well as a layer of torn cartilage under the knee cap.  I have a history of blood clots from previous surgeries so I was sent home on blood thinners.  Two days after surgery I began doing straight leg raises as I knew these would be required when I started physical therapy (as I stated I have had numerous surgeries on this knee due to congenital issues).  Well about a week after the surgery I could no longer lift my leg.  I stayed in PT for approximately 4 months when I lost my insurance but have had significant atrophy of the quadracep muscle and constant pain in the knee.  I was referred to a Nuerologist who has diagnosed me with Femoral Neuropathy.  I have been unable to obtain much information but it is six months later and I must wear a brace at all times - I am still on pain meds as the pain has not decreased at all and PT just makes the pain worse.  My orthopedic has suggested that the pain is due to my not having the quadracep muscle to take the brunt of the force on my knee.  I no longer drive a car and must be VERY careful on uneven ground and stairs as even with the brace my knee lets go all the time.  The pain is so significant that I have trouble wearing pants as any pressure at all on the knee is horribly painful.  I feel like I am not getting any real answers as to how this happened (although my neurologist has hinted it could have been the nerve block) nor how to really fix this.  They just say I need to keep going to PT.  Any and all suggestions or information would be greatly appreciated.