My 19 year old cat uses her litter box regularly. However, she has the bad habit of jumping in it, and poops with her butt hanging over the edge. So, basically, she is now pooping on the floor.
If we put a lid on the litter box, or try making "sides", my cat refuses to go in it. If we try moving her hind end a bit when she goes, she stops going.
We can't say she isn't using her box, because she is... She just misses the actual box. Help!
Be overjoyed that your cat has lived to being 19 years old and is still going strong! Imagine how many problems or difficulties you may have in your extremely elderly years... Missing the box, while it may be a bit annoying, is not all that uncommon and certainly is the least of the problems that your cat could be facing in her senior years.
Honestly, there is little you can do to correct this litter box problem. Because of your cat's age, she is likely just using the box in the most comfortable way she can. The best thing to do would be to line the floor around the cat litter box with paper towels or trash bags to make it easier to clean up.
Congratulations on having so many years with your cat! Enjoy every moment!
All the best,