Hi, I have had 2 ACDF surgeries, the most recent one being February 2018. I have had three levels replaced so far and my spinal cord was too compressed to fully bounce back last time, with signal change . Last night, due to osteoarthritis, my knee suddenly gave way and I went straight down onto the ground on my bottom (butt) with a bang. I felt as if my body had shifted up to my head and my head felt under pressure. Today I feel extra physically fatigued and have a hot wrap at my neck. I am just concerned if I could have done any further damage or not or is the neck more solid after the operations due to the titanium discs and fusion?