Why is a lame dog lame? The obvious, but incorrect, answer to the question is ‘because it has a sore leg’. The correct answer is more complicated, but also quite obvious when you think about it.
Firstly, what is a lameness? Everybody knows what a lame animal looks like – they ‘walk wrongly’. But what is happening to make them walk wrongly? There are three main reasons why lameness may occur.
Pain is the most common and most important cause of lameness. If an animal damages a limb, any further pressure causes more pain, and so the instinctive response is to rest the limb, by carrying it, or at least by not putting full weight on it. The type of damage can vary widely from a bruise to a laceration. The damage can be anywhere in the limb, from the toe to the shoulder or hip, and the result is the same – a lame animal. Long term diseases such as arthritis can also involve considerable pain.