These growth plates are more easily fractured because they are the weakest part of the bone. The distal ends of the femur and humerus seem to be particularly susceptible to this fracture. Greenstick fractures are small cracks within the bone which leave the bone basically intact, but cracked. In other words, the bone is not completely broken. The symptoms and risks depend on what area and to what extent the bone is fractured.
Fractures involving a joint are the most serious.
A broken back may displace the spinal cord and cause complete paralysis. All fractures however, are serious and should be treated at once. When a bone within a leg is broken, the dog or cat will usually hold the entire leg off the ground. No weight is placed on the paw. With a sprain or lesser injury, it may use the leg somewhat, but walk with a limp.