I"ll try to help:

L4-5 disco-osteophyte bulging: this is a disc bulging along with bone spurs. Plus there is moderate to severe spinal canal stenosis, which is narrowing of the spinal canal.

There is "disc degenerative changes" - this is a drying out of the discs which comes with age. Everyone gets it. When the discs dry out, they tend to flatten, which makes them bulge. When they bulge they CAN herniate. When they bulge OR herniate they can press on nerves, which cause pain. They note that there is spinal canal stenosis, which is greater at the level of L4-5, so evidently it's pretty well throughout the spine.

This doesn't indicate any surgery at this time, but I'd talk to his doctor cause I'm NOT a doctor!! If your father is having any neurological symptoms like tingling, numbness, pain, etc., make sure the doctor knows all about it. Keep looking for ANY changes in his condition too because any change could indicate a herniation or worsening of his condition.

If you have more questions, let us know. Best of luck & God bless. Hugs, Lee