Bone and Growth Issues in Papillon Puppies: Small Bones, Different Rules

An open fontanel sits on the Papillon's documented health list, and it is the one growth finding specific to this breed. In most dogs the plates of the skull fuse in the first months of life. In some toy dogs a gap at the top of the head, roughly where a human baby's soft spot is, narrows but never fully closes.

A small, persistent fontanel in an otherwise normal dog is common in toy breeds and is often of no clinical consequence at all. Many Papillons live full fourteen to sixteen year lives with one and nobody thinks about it again after the puppy check.

What it does mean practically is that a patch of brain is protected by skin and membrane rather than bone. That is worth knowing before a child carries the puppy, before rough play with a larger dog, and before any procedure where a small head is being positioned by someone who has not been told.

A large fontanel, or one that seems to be getting bigger, is a different conversation and should be assessed, since it can accompany other developmental problems.

If a Papillon puppy is going to break something, it will most likely be the radius and ulna, the paired bones of the forearm, and it will most likely happen indoors from a jump or a fall out of someone's arms.

These fractures are notorious in toy breeds for two reasons. The bones are slender, so there is little margin for a plate or a pin. And the blood supply to the lower part of the radius in a very small dog is sparse, which means these fractures heal slowly and sometimes fail to heal at all, leaving a non-union that needs further surgery.

This is the single strongest argument for the rules that sound fussy in a puppy's first year. No jumping off sofas. No being carried by a child who is standing up. No leaping from an adult's arms at the door. A dropped Papillon puppy is a genuine orthopaedic emergency, not a fright.

Growth plates in the forearm are also open until around six to eight months, and an injury through a plate can stop one bone growing while its partner continues, producing a bent limb.

If you think your Papillon has bone & growth issues, the plan is three steps: write down what you have seen and when it started, book a veterinary appointment rather than waiting for the next flare, and take video of the behaviour or symptom before you go — the thing you are worried about rarely happens in the consulting room. Screening in the parents covers patellar luxation, progressive retinal atrophy, dental disease.

What the vet visit should produce is a diagnosis and a written plan, not just reassurance: what is being ruled out, what the monitoring interval is, and which signs mean you come back sooner. Ask what the treatment costs across a year rather than per visit, because that is the number that decides whether you are managing this condition or reacting to it.

Between appointments, keep a short log — dates, what you saw, what changed. It is the single most useful thing an owner brings to a follow-up, and for bone & growth issues it is often what separates a clear pattern from a guess.