Cat Anatomy – or Catnatomy! A Look Inside Your Cat

Trent Webb

Do you know where your cat’s liver is? How about their phalanges? They’re constantly in our lives and on our laps; yet under the skin and on the inside, they are a mystery! Here’s our cat anatomy 101…

It’s fascinating that our cats share most of the same key bones and all the same internal organs as humans. Yet if we look inside, their feline arrangement is simultaneously and curiously similar and wildly different enough to merit a look at Felis Catus with x-ray eyes!

Cat Anatomy 101: The naming of parts

We’ve all stood there when either our own doctor or the vet has thrown out the name of a bone (“it is their ischium”) or assumed we know how the organs are arranged (“just below the lungs”) and not been 100% sure of what they mean. We should stop them and ask, but embarrassment or shame or something just makes us nod as if we know.

So the aim of this guide is to provide a primer of the feline internals, so next time you’ve got a better idea of your cat’s internal geography – both the bony bits and squishy stuff.

Nose to tail

There’s one end with teeth and one with a tail – but what really lies between the two? Do you know where their stomach stops and the small intestine starts? Could you find their spleen in the dark?

The internal organs of the cat - not just A cat mind you, but THE cat!

Now, don’t go planning any major surgery on the back of this chart, it is diagrammatic. Obviously something has to fill the white space shown and their skeleton (which we’ll get to in a bit) will fill all that space! That’s muscle or at least it should be, but these are way too interwoven and layered to make for a comprehensible diagram.

Where you spleen?

What it does illustrate is the sequence of the organs and relative size. That relatively high (in relation to their head) position of the liver is always a surprise. Similarly, that their heart and kidneys are tiny; while the lungs and digestive systems take up about 50% of the internal space available. The actual location of the spleen will always be a mystery – cover up the labels and try and find it! While the relatively small bladder indicated will be disputed by anyone who has had to clean up after an unneutered tom!

The cat's skeleton - time to play find the phalanges!

The incredible flexibility of cats comes from their additional vertebrae. While they only have one more than humans, they’ve packed few extras thoracic and lumbar sections, and have a less complicated back end – courtesy off being quadrupeds rather than bipeds. This means they’ve more scope to twist and bend, as everyone who has tried to give a cat a tablet will attest.

Shoulder the blame

The other key skeletal difference is that a cat’s forelimbs are attached to the shoulder via free-floating clavicles – hidden in this diagram under the Scapula (shoulder blade), whereas humans have a fixed collar bone. This allows cats to fit through any gap they can fit their head into.

Humans should also be jealous of the elastic discs between a cat’s vertebrae, which helps cushion landings. Just standing up from the chair feels like we’ve jumped off the kitchen cabinet for many of us!

Just eat

The other key skeletal feature of cats stems from their predator heritage. They have very large eye sockets (albeit relatively regular sized eyes to go in them) and powerful jaws. Domestic cats have further differentiated themselves from their ‘big cat’ fellows by developing narrowly spaced canines, perfectly suited to their historic snack of choice – rodents.

Your cat’s anatomy? Check them out

So next time they snuggle down on your lap or stretch out next to you, see how many bones or organs you can place with a gentle prod… and then get your phone out, so you can check the diagrams. Now the spleen, that was by the ear… right?

This Cat Anatomy post is an opinion and should only be used as a guide. You should discuss any change to your pet’s care or lifestyle thoroughly with your vet before starting any program or treatment.

If in doubt contact your veterinary practice

And always keep your vet's phone number handy - just in case!