I Am A 52 Year Old Male. I Have A

I am a 52 year old male. I have a 3 tier spinal fusion l3-s1. My problem is severe burning in my right buttocks that goes all the way down my leg. I have recently been having a lot of pain and stiffness in the fusion area.
I am also having bouts of muscle weakness in my hamstring and hip flexor areas on both legs. I am also having severe muscle cramping at nights in my calves and toes as well as my hamstring area of both legs