WHY GROWING PUPPIES ARE VULNERABLE
Most of your dogs growth occurs between four and eight months of age. The bones grow and lengthen -- a process made possible by the growth plates at the end of long limb bones.
When a puppy reaches about 18 months old, the growth plates seal closed. After natural closure of these plates, an injury to the leg won't result in the overwhelming damage or deformity seen in younger dogs which is why you must take care while they are growing.
However, if an immature growth plate-which is often softer than other parts of the bone- becomes injured, the damaged cells stop growing. Meanwhile the uninured cells continue to grow.
Since growth plate injuries typically occur on one side of the plate or the other, the damaged side of the bone quits growing, but the healthy side continues to grow. This is how the bone ends up anything but straight.
HOW A CURVED OR BOWED LIMB DEVELOPS
The most common angular limb deformity occurs in a puppy's forearm, which has a two-bone system comprised of the ulna and the radius.
If the growth plate of either of these bones is injured(usually it is the ulna) the damaged bone will stop growing, but the other bone can develop all three deformates- it can bow, curve AND rotate.
Younger dogs who are still growing especially large and giant breed puppies are at much greater risk for developing a deformity than older animals after a traumatic injury.
If the problem isn't diagnosed quickly and corrected with surgery, there can be much bigger problems in the future for the injured puppy.
Needless to say, the goal of any pet owner should be to avoid trauma to a growing puppy altogether!!!!
This is why veterinarians warn new puppy parents not to engage their pets in rigorous jumping or other very strenuous exercises until all growth plates have had time to close. Having a puppy play too hard for too long with oversized adult dogs can cause lifetime of issues so we strongly suggest to curb this until puppies growth plates have closed.
Many proactive veterinarians, encourage pet owners to provide high risk puppies with joint support to help reduce damage to growth plates.
Slow rate of growth is also imperative which is why we insist on our puppies being fed a 26 % protein food and NOT A puppy food.