Is there any chance your cat has arthritis? They don’t show the same symptoms as dogs (or people) with the condition and it can be much harder to recognise - but it’s just as painful and debilitating. This blog aims to bring you up to speed on what may be the most underdiagnosed cause of feline suffering!
Surely it isn’t common in cats?
Yes it is - about 90% of cats over the age of 12 have some degree of arthritis. Roughly 30% of those are in the spine (a condition called spondylosis), but the remainder of these cats are suffering from the same limb joint arthritis as older dogs and people do. And yet the majority of owners don’t know how to recognise it, meaning their pets suffer unnecessarily.
What is arthritis?
Arthritis just means “inflammation of a joint”, and there are several types; in this blog, however, we’ll be focusing on osteoarthritis - also known as degenerative joint disease or “wear and tear” arthritis. This is actually quite a complicated disease, involving chemical and physical changes to the structures inside the joints, but the end result is fairly straightforward.
The joints become swollen but the quality of the joint fluid (the lubricating liquid inside the joint space) worsens, becoming thinner and less able to protect the joint from shock or even normal movement. This triggers further inflammation, setting up a negative spiral.
At the same time, the cartilage (the “teflon” non-stick coating inside the joint) is progressively worn away, until the bone is exposed, leading to bone rubbing on bone (a process known as “eburnation”). To try and stabilise the damaged joint, extra bone forms around the edges (osteophytes and enthesophytes), but this makes matters worse in the long run by limiting the joint’s mobility. As the joint becomes stiffer, the cat isn’t able to take weight on it normally, so more damage is done.
All of these processes are painful - there are pain receptors in the joint capsule and the bone under the cartilage, as well as the surrounding tendons and ligaments, and these are all stimulated by the inflammation and the structural changes inside the affected joints.
What causes it?
This is less well understood than in dogs or humans, but the basic principles appear to be the same:
● Normal weight being carried on a damaged joint or limb. Typical causes would include:
○ Hip dysplasia, where the hip joint is malformed - especially in Maine Coon cats, but seen in other breeds as well.
○ Patellar luxation, where the kneecap becomes dislocated, most common in Abyssinians.
○ Following a fracture that damaged the joint.
● Excessive weight being carried on otherwise normal joints (e.g. being overweight or obese) - this may not trigger arthritis but it certainly makes it worse!
● Simple wear and tear in old age.
Other known risk factors include cartilage defects such as those suffered by Scottish Fold cats, and Acromegaly, a hormone disorder.
OK, so what are the symptoms in cats?
Cats are very good at hiding their pain, so they often suffer in silence. The most common symptoms are:
● Reduced mobility:
○ Difficulty jumping, for instance onto furniture or up and down stairs.
○ Struggling to get into or out of the litter tray - this can present as incontinence because the poor cat can’t get into the litter tray to use it.
○ Less time spent out and about.
○ Reduced grooming, because it hurts to stretch round and clean themselves.
● Altered temperament:
○ In many cases, cats become more grumpy or irritable.
○ Most affected cats will spend less time playing, and more time sleeping or hiding.
○ Often, cats will avoid interacting with people or each other.
The trouble is, of course, that many people mistake these signs for simple old age - when in reality they’re due to chronic, unremitting pain. If you have an older cat, you can download a Mobility Checklist from International Cat Care, which may help you to notice subtle changes that could indicate arthritis.
What can be done?
Although arthritis is incurable, most cases in cats can be managed with medication - usually painkillers and anti inflammatory drugs such as meloxicam (a liquid that goes on their food). If they are overweight or obese, though, weight loss alone has been shown to be as effective as a dose of a painkiller!
Some environmental modifications can also help - a warm, soft place to sleep is something cats are usually good at finding for themselves, but a little extra help is important for arthritic pets! Providing them with ramps and easy access pathways and low, or ramped, litter trays can also be really helpful, as can regular grooming to prevent mats from forming in their coat.
If you think your cat may have arthritis, make an appointment to see one of our vets, and we’ll work with you to keep them comfortable, happy and mobile!