What Causes Foul Smell From Injured Finger?

MASHED FINGER 2 WEEKS AGO AND IT ALSO CRACKED THE BONE AT THE TIP FINGER IS DOING REALLY WELL WITH NO SORENESS AND VERY LITTLE SWELLING THIS MORNING IT HAS STARTED STINKING LIKE SOMETHING DEAD AND I HAVE KEPT IT VERY CLEAN WHAT CAN I DO ABOUT THE SMELL