I was in an Mech Infantry unit in Germany. We had a guy develop bone spurs. He wanted to stay in and even asked for a surgery to removed them. Nope, they put him out. Not enough Orthopedic surgeons available at that time.
I developed a bone spur when I had 15 years in the USAF. No one ever mentioned putting me out. I went on to retire at 20 years. I was in a critical career field. Maybe that was the reason.
My high school classmate, at the height of the Vietnam war, was rejected by the Army, due to flat feet.