The Fusion of L4-L5 is this with metal in your back? That is a very difficult process to heal.
I had non invasive L4-L5, L5-S1 and piriformis release. I had nerve damage that left me legs useless and very painful even when laying down. After surgery the painful current movement in my toes went away but the nerve damage has been a real slow progress to get some kind of QOL back. There are yoga stretches on youtube that make a significant difference each day you do them for hip and legs. It helps the whole body. Hydration with minerals every morning. So many natural things I am discovering make a little difference each day. I am really imbalanced and that starts in the brain. There is a heaviness on the left side of the brain. I must use a cane so I don't fall. I am trying to concur that with the yoga exercises. Have a good day. Don't give up.