Especially on smaller breed dogs, the sacs have to be released ever now and then to avoid them from becoming impacted.
If you see your dog scoot his little bottom on the floor, think of anal sac impaction (It is very common in small breed dogs)
If you encounter a open wound like that on you little Papillon, wash his rear with sudsy warm water, apply a topic antibiotic cream on the wound and make a quick appointment with the vet!!
There are things you can do to help prevent these anal sac problems:
A good quality diet to maintain a solid, slightly firm stool. (The stool pushes against the anal sacs while eliminated)