The Everton keeper said that his injury, sustained in Saturday's 1-1 draw with England, has improved and, while they are likely to be sore, he expects to play on Friday against Slovenia.
"It's getting better," said Howard. "Time is a good healer. It's going to be sore. I'm a firm believer in adrenaline. You can't get enough of it. I feel like once I get out there, I will be ready. I won't be stopped by it. If you play at the highest level, I think you have to play through injuries."
The 31-year-old will not be looking for a deeper diagnosis than that of bruised ribs for now, saying they do not feel broken. "Not knowing is probably better," Howard said. Although, he added: "If the docs and the medical team felt like I needed it, I would certainly do that. I won't be stupid with it. At least I don't think I will be."