My first P&Y animal was a big Bear I shot with a Recurve. When I gutted him I found the back 8" of an aluminum arrow from the year or 2 before. It was a high shot above the lungs and had broke a rib, nicked the spine and nicked the rib on the far side and completely healed up and you would never have known by looking at him. Healthy as could be. Like said previously, tough mothers