How This Happens
Dogs that are prone to this due to soft, weak rings may start to have issues as they mature. However, in most cases it will be pressure on the neck that causes this to happen, regardless of whether or not the dog is predisposed.
When too much stress is put on the Maltipoo's neck, the rings can collapse. It is sad that many owners do not realize how easy it is to avoid this from happening. In the majority of cases, the happens when the dog has a collar put on them, and then that collar is attached to a leash. When wearing the collar, all it takes is a moment in which the dog lunges forward or tries to take off running and the owner is caught off guard, unable to keep up....That one "jerking" motion is all it takes to cause Collapsed Trachea. And then, there is no turning back.
Alternatively, it may not be just one event; it can be a slow, gradual yet constant 'wearing down' as the dog experiences tension to the neck over the course of months or years.
Puppies
that are not yet trained to listen to all commands are most susceptible to this. It is very normal for a puppy to be outside, see a butterfly or flying insect and instinctively leap forward to try and catch it. If the Maltipoo is wearing a dog collar and is connected to a leash, if they jump with force and the leash stops them mid-action, all the stress of their jump is put directly onto the neck...and that is what causes this.