When spoilage occurs in the bone, you see that the meat on it becomes loose and flabby, begins to stink and fester. The knitting needle penetrates it in the easiest way, and when it reaches the bone, it turns out that the bone is not smooth, and the knitting needle does not slide along it, but sticks slightly, as if it encounters something not strong, but crumbling and rotting. Sometimes the bone crunches and is soft, especially if the damage is not in the initial stage - in the initial period such phenomena are not detected by the knitting needle, and bone damage is sometimes indicated even by excessive sliding of the knitting needle when hitting the bone. If the knitting needle slides along the bone in all directions, this indicates that the shell of the bone has separated, and this is due to deterioration that has already begun or is just beginning, when the meat on the bone deteriorates, exposing the meat, you see that its color has changed. Spoilage is often preceded by swelling, deterioration and death of the meat, and then the spoilage spreads to the bone.