Yosef Karo, Shulchan Aruch — 53 The law of a fracture or wound in a beast
“ Some forbid it if it's broken close to the body and consider its rule like a part that's unconnected (H"M) and the custom that's become prevalent is that if there's approx. a thumbreadth width even a small amount it's kosher (Agur et. al) as long as he doesn't see a blood clot on the other side of the ribs - but we don't suspect that and we ordinarily consider it kosher (Maharik et. al) . ”
Yosef Karo, Shulchan Aruch — 53 The law of a fracture or wound in a beast
“ But if it's found unconnected and it's unknown whether before shechita or after shechita it's proper to be stringent and forbid it, and see below the end of Siman 110. 5 A bird that had a deep wound under its wing against the lung and they put a feather on the wound and inflated it through the windpipe via a thin straw and the air doesn't leak out - he should fill the wound with water and blow into a straw through the windpipe; if the water bubbles it's treif. ”
