Poor posture contributes to weakening of the core muscles in dogs, just like it does in humans. This can cause myofascial back pain, spinal luxation, and spinal muscle tension. Over time as in humans it can cause joint pain, muscle loss and mobility issues.
However it is worth noting that dogs in particular use there posture to express their feelings
A dog’s weight distribution can tell a lot about mood and intention. A cowering dog with a posture hunched toward the ground is also sign of fear or stress, as it can be of pain.
A dogs behaviour and posture will be used to help with the diagnosis of acute or low grade pain issues.