What Causes Severe Pain In Knee Post Knee Replacement Surgery?

10 years ago I had a routine half knee replacement and experienced a lot of pain for about 3 months.Tte surgeon found pieces of cement in the knee ( excess from the op had not been wiped off) He removed the bigger pieces but said it was impossible to find all the smaller bits.I still suffered a lot of pain and found walking difficult ,although was able to cycle as there was no weight on the knee.Iwas referred to a neurologist ,who diagnosed M N D and gave me 6or so months to live .I am still alive and the neurologist has now changed his mind and that I now have neuropathy.I still have extreme pain in my knee at the top of the tibia .I had a revision full knee 3 years ago but the problem has not gone away.Any thoughts?