Why did Christopher Timothy limp in the series All Creatures Great and Small?

Christopher Timothy's character, James Herriot, limped in the series "All Creatures Great and Small" because he had a war injury from World War II. In the series, it is revealed that Herriot sustained a leg injury while serving as a veterinary officer during the war. This injury causes him to have a noticeable limp throughout the show, adding depth to his character and backstory.