hi
i currently have a miniture poodle who has also gotten the same little black crusty spot on his back around his shoulder right at his neck line it started really small now it is about an inch and looks like a burn healing
it is a hot spot you can treat it with sulodene get it at your local pet store ask for the best treatment for hot spots
hot spots are caused from the dogs sweating and usually most common in long haired animals my poodle wore short hair all summer i let it grow through fall and into winter shave the area and treat it as the bottle suggest it takes 7-10 days to heal
i hope this helps and your fur baby feels better son
It could be a traumatic injury, and is now healing. It could also be a histiocytoma, or a wart. Both of these dermal masses are benign. Histiocytomas are common in young dogs.
Your vet will be able to give you a definitive diagnosis and treatment.