Cat Back Legs Collapsing: Causes, Symptoms, & Treatment

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cat standing up holding onto a human

All cats should be able to walk, run and even jump easily, with strong, well-balanced back legs. There are a number of conditions that can affect the back legs, causing lameness, weakness, lack of stability, poor balance, and even complete collapse.

This article aims to explain the different reasons why the rear legs may become weak and collapse, along with the investigations needed to diagnose the cause of the problem, and the possible treatment options that may follow.

What Does It Mean When A Cat’s Back Legs Collapse?

Cats have powerful back legs, used to help a cat prowl, run, climb and jump as part of their normal activities, such as hunting. The function of the back legs is supported by a combination of strong muscles, with a rich blood supply, and an intricate nerve supply.

The muscles, blood supply and nerves can stop functioning normally for a number of different reasons, and when this happens, the back legs can become weaker, unable to support the cat’s weight properly.

This causes the cat’s hindquarters to flop down, either being carried lower than normal, or even collapsing completely, so that they are being dragged behind the cat. The issue may start with the cat just limping, then progress to more serious signs with difficulty walking.

Owners may notice the signs when the cat is carrying out certain specific behaviors, such as going upstairs, or using the litter box.

  • Paraparesis is the technical term that means weakness of both hind legs
  • Paraplegia is the technical term that means complete paralysis of both hind legs

With some causes, the front legs may also be affected: if all four legs are weak, this is known as quadriparesis, and if all four legs are paralysed, this is known as quadriplegia.

How Common Is It For The Back Legs To Collapse?

Paraparesis (weakness of the back legs) is common, while the more severe situation of paraplegia (paralysis) is less common. Both conditions are seen regularly in busy vet clinics.

What Causes The Back Legs To Collapse?

Any condition which disrupts the muscle or nerve function, or the blood supply, of the back legs can cause them to collapse.

The main common causes are listed below.

  • Spinal disease, from trauma to slipped discs to tumors, can stop the normal functioning of the spinal cord providing the nerve supply to the back legs, leading to weakness and collapse. Rarely, some diseases affecting the central nervous system (brain) may be involved.
  • Vascular disease, such as blood clots (e.g. thromboembolism affecting blood vessels such as the aorta, known as a saddle thrombus) can disrupt the blood flow to the back legs, causing severe weakness and collapse. Heart disease such as cardiomyopathy can predispose to this issue.
  • Metabolic diseases, such as feline diabetes mellitus, can cause unusual signs (such as a neuropathy causing a plantigrade stance of the hind legs) which may present as the collapse of the back legs. Other metabolic diseases (such as kidney disease) can cause weakness which can present as rear leg weakness. Older cats may be more prone to these types of issues. Sometimes generalised diseases, such as feline infectious peritonitis, may also cause the back legs to collapse.
  • Trauma of any kind can damage the physical structure of the back legs, from the feet up to the pelvis, causing collapse. This can affect the soft tissues (e.g. sprains of muscles and tendons), as well as the bones. Nerve damage is also possible.
  • Old age changes, including osteoarthritis (e.g. due to hip dysplasia) can lead to lameness, weakness and collapse of the hind end of the cat.

Symptoms Of Collapse Of The Back Legs

cat stretching it front legs

When the back legs collapse, the hindquarters are held lower than usual, and the back legs do not move normally. If this happens, you should take the cat to your DVM veterinarian without delay.

The back legs should be strong, holding the hindquarters up in a normal position, and the legs should move in a normal fashion, coordinating well, allowing the cat to move normally.

When the back legs collapse, the hindquarters are held lower than usual, and the back legs do not move normally, dragging behind the cat, or stumbling, or allowing the feet to be in the incorrect position (e.g. the upper side of the feet being dragged on the ground).

Investigating Collapse Of The Back Legs

As part of responsible pet care, if your cat develops a collapse of the back legs, you need to take them to your DVM veterinarian without delay, so that the cause of the problem can be identified and so that treatment can be given. Your veterinarian may take the following steps:

1. Detailed History Taking

Your vet will discuss every aspect of your cat’s condition and review their overall cat health. There are a number of different possible causes of the collapse of the back legs, and this history will help to differentiate between them. Senior cats are more prone to certain problems than younger cats.

2. Physical Examination

Your veterinarian will check your cat’s body carefully all over, feeling the back legs, pelvis and spine carefully, searching for any physical abnormalities such as instabilities, swellings or disruption. They will also carry out a neurological examination, checking your cat’s reflexes to the hind legs. They will pay particular attention to the affected limb if only one hindlimb is affected.

A complete full physical examination of the whole cat is also carried out, in case there are other signs of illness that could contribute to the rear limb problem. This will include taking the cat’s temperature and listening to their chest with a stethoscope.

3. Routine Blood Tests

It’s very likely that your veterinarian may carry out blood work, including the usual panel of diagnostic tests, such as hematology (blood count) and biochemistry profiles (including important electrolytes such as potassium). This is known as the minimum database, and it’s carried out to review most sick cats, regardless of the signs of illness.

4. Specialised Blood Tests

Your veterinarian may recommend specific blood tests for some viral infections such as FeLV and FIV, since there are significant implications if your cat is positive for either of these.

5. Other Tests

Radiography (x-rays) may be taken to examine the details of the structure of the spine, pelvis and hind legs. Depending on the case, more detailed diagnostic imaging (such as CT or MRI scan) may also be recommended.

Blood pressure measurement may be recommended in some cases.

How Much Does It Cost To Treat A Cat With Collapsed Back Legs?

vet taking care of a cats dysfunctional leg

Costs and treatment for the collapse of the back legs is very variable, depending on the cause and severity.

It is impossible to estimate this cost, as there are so many possible factors going on in the background of individual cases. You should ask your veterinarian for a detailed estimate before agreeing to proceed with treatment.

Costs could vary from €400 for a simple case to €4000 or more for an exceptionally complex case of the collapse of the back legs.

Treatment For Collapse Of The Back Legs

Treatment for the collapse of the back legs is very variable, depending on the cause.

  • Spinal disease causes may just require strict rest, combined with anti-inflammatory medication, or in severe cases, spinal surgery may be needed to solve the issue.
  • Vascular disease, such as blood clots (e.g. aortic thromboembolism) need intensive veterinary care, including pain relief and anti-inflammatory medication, as well as treatment of the underlying heart disease.
  • Metabolic diseases, such as diabetes mellitus, require stabilization, with the specific treatment for the metabolic problem (e.g. restoring normal blood glucose levels in diabetes mellitus).
  • Traumatic injuries need treatment for the physical damage, from anti-inflammatory pain relief, supportive supplements, and strict rest (e.g. keep your cat indoors, but away from your dog) in minor cases, to surgical correction (e.g. some fractured bones).

Monitoring And Prognosis

Again, this depends on the individual case, but in general, cats with collapsed back legs need frequent rechecks by their DVM veterinarian until they have returned to normal. As well as frequent physical rechecks, repeated blood samples and radiographs may be taken to monitor any changes.

Many cats make a full recovery, but the prognosis depends entirely on the individual case, and your own veterinarian will be able to give you the best answer to this question.


The collapse of the back legs, with either weakness or full paralysis of the back legs, has many possible causes, and should always be investigated and treated as soon as possible by a DVM veterinarian.

Frequently Asked Questions

What can cause collapsed back legs in cats?

Possible causes include trauma, spinal disease, vascular disease and metabolic disease (such as diabetes mellitus).

How do I know if my cat has collapsed back legs?

If your cat is unable to walk, run and jump on their back legs, then they are suffering from some degree of collapse of the back legs.

Can a cat survive collapse of the back legs?

Most cases of back leg collapse respond to treatment, but there are some serious causes (such as spinal fracture) where successful treatment may be impossible, and your veterinarian may recommend euthanasia.

How serious is collapse of the back legs in cats?

This is a serious condition that always requires a prompt examination by your DVM veterinarian.

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About Dr. Pete Wedderburn, DVM

Dr Pete Wedderburn qualified as a vet from Edinburgh in 1985 and has run his own 4-veterinarian companion animal practice in County Wicklow, Ireland, since 1991. Pete is well known as a media veterinarian with regular national tv, radio and newspaper slots, including a weekly column in the Daily Telegraph since 2007. Pete is known as "Pete the Vet" on his busy Facebook, Instagram and Twitter pages, regularly posting information on topical subjects and real-life cases from his clinic. He also write a regular blog at His latest book: “Pet Subjects”, was published by Aurum Press in 2017.

18 thoughts on “Cat Back Legs Collapsing: Causes, Symptoms, & Treatment

  1. Deb

    My cat has kidney stones and his back legs have become more weak the past week. We changed his diet about 3 weeks ago. What else can I do for him?

    1. small mallory photoMallory Crusta

      Deb, if you haven’t already seen a vet, I would recommend doing so. Kidney stones are a serious issue that requires immediate treatment. It’s essential that you dissolve the stones and get your cat urinating properly immediately. Depending on the severity of the condition, catheterization may be necessary.

      1. Deborah A Mintz

        Thank you, have been seeing my vet. Pretty sure he has another uti, so taking a sample to the vet tomorrow. My cat acts totally normal, except for his gait. Which is why I took him to the vet as soon as I noticed it.

  2. Deborah A Mintz

    Thank you, have been seeing my vet. Pretty sure he has another uti, so taking a sample to the vet tomorrow. My cat acts totally normal, except for his gait. Which is why I took him to the vet as soon as I noticed it.

  3. Mandi W

    About a week ago my cat started acting ill. For about 48 hours he wouldn’t even eat or drink. After 48 hours or so, he finally started drinking and eating, but VERY little. So about 72 hours into this I noticed that he is walking as if he was drunk. And this has progressively gotten worse. Now he almost has no control over his back legs, collapsing every other step or so. I have taken him to my vet, they took x-rays, but said everything there checked out okay. They wanted to do about 6-8 other tests on him but it was gonna cost me over 600$. Sad to say I had to decline but they did give him 2 shots of an antibiotic and something else and sent me home with some antibiotics. It’s been 2 days with no progress . He doesn’t even know when he is pooping. I feel so bad for him because I do not know what to do and my vet doesn’t know what’s wrong and the poor guy can’t even walk. Please help.

    1. Avatar photoDr. Pete Wedderburn, DVM Post author

      Hi Mandi – there are so many possible causes of this but it is impossible to say from a distance. Examples include blood clots in his spinal cord- and the problem for you is that making this type of diagnosis can only be done by doing extra tests like MRI scans, which are pricey. The best you can do is to keep engaging with your hands-on vet, and they will at least be able to help you nurse him through this crisis. Hopefully he will start to improve soon.

    1. Avatar photoDr. Pete Wedderburn, DVM Post author

      The best approach would be to take him to your vet, and get a diagnosis made before making any decisions. There are many reasons why cats can get weak on their back legs, and some are very treatable. So get a vet’s opinion, and after you’ve done this, you should be able to work out the prognosis for your cat, and then you can reach a carefully considered decision which is more likely to be the correct one.

  4. Judy

    my 12 year old cat developed diabetes last spring. It took months to get his glucose level stabilized and a month before this occurred, he developed weakness in his back legs, walking on his hocks .B12 was prescribed, but this has not improved his walking. He is now having acupuncture treatments to help with the blood flow. I can see he is more comfortable and now carefully jumps up on my lap in the evenings. Will he ever improve completely? He does not complain: loves being petted and groomed, and tickled with his feather stick. and slowly and carefully straddles each step going to his litter box. Takes the acupuncture treatments comfortably, just complains about getting there – not fussy about car rides.

    1. Avatar photoDr. Pete Wedderburn, DVM Post author

      I am afraid that this is not easy to predict. There are many possible reasons why this could be happening, from low blood potassium to arthritis to spinal issues. I am sure your veterinarian has been looking into these possibilities, along with the treatments that could be used to help if these were suspected. My advice is that if you have concerns, do talk to your veterinarian about them, and often an answer can be found.

    2. Kala

      Have you tried zobaline you can look it up on Amazon it’s methyl b12 … I give it to my cat but unfortunately haven’t been able to get his diabetes treatment started and just diet isn’t enuff. He was diagnosed on the 7th of March this year. And I took him in for it at first they said arthritis but then when blood work came back it was from diabetes. I feel like I am the worst fur mama ever. I have applied for assistance but no luck yet. But if you look it up on Amazon there are a lot of reviews you can read and you can always ask your vet.

  5. Megan

    My poor little kitty died. I’m heartbroken and can’t help but wonder what happened. He had sore hip bones, couldn’t jump like he used to, couple lumps when he finally let me feel around, his teeth were wore down and weak, then on Christmas I gave him his new catnip mice and favorite food and he wouldn’t play or eat, then his back legs were weak but he was walking and drinking and using his litter box, but he started to hide in the back under bed. Then he quit drinking water for day then couldn’t move around much, just wanted to hide, he fought to breath, pissed, howled in pain last hour before he passed. He was over 15 but seemed fine just days ago…I called two closest vets and it was day after Christmas and one had no vet til after new year and the other was able to see him following morning but I was 2 hours away in a blizzard that dumped feet of snow. My cat hated going in vehicle and it caused him much distress so I didn’t want to put him through it, I think trip would have killed him anyway….he passed that next day within hours of appointment. Can you help shine any light on what happened or what I could have done better for my little love,

    Thank you

    1. Avatar photoDr. Pete Wedderburn, DVM Post author

      Hi Megan – I am so sorry to hear this. Howe completely devastating. You say he was over fifteen, and that holds the key to the answer. He was an elderly cat, and elderly cats are prone to a long list of challenging issues, including kidney failure, high blood pressure and heart failure, as well as internal cancers. There is no way that such diagnoses can be made by just looking at a cat – a series of investigations need to be done by your vet. Some people do that, and yes, that is the ideal perhaps, if length of life is the only goal. But going to the vet does involve stress for the cat, it does involve expense that people may not be able to afford, and it does not always mean that you reach the goal of a longer life: some conditions remain untreatable. From what you say, your cat’s issues were advanced and I do think that it would have made no difference to him, even if you had been able to reach the vet. The only way to know for sure would be to have a full autopsy carried out, but it would make no difference anyway. You have my deep sympathy for your loss. Great love brings deep sadness at the end, always. We focus on the sadness, but remember, the only reason you are sad is because of the love. The only way to avoid the sadness would have been to avoid the love. And you would never have wanted to do that. Take care. Pete

      1. Megan

        Thank you for reply, my sweet boy was my favorite thing in this whole world and I would take any amount of pain and loss for him. Cats heal the soul. He was a fighter from his first breath to his last and I was so blessed to be his ♡

        1. Valerie Anderson

          My deepest sympathy to you on your
          My Tommy is 18 1/2
          Years old and having kidney stone issues now and finding it difficult to walk. I have a vet appt in 2 days. I’m dreading the appt but I don’t want my Tommy to suffer needlessly. We love our fur babies so much and they love us in return.

  6. Sue

    Our 12 yr old cat has hyperthyroidism and takes 5mg methimazone daily. As a result, she has gained a good amount of weight back. Previous blood tests for diabetes were normal. In general she seemed OK, eating and drinking regularly. We were away for a week and when we got back, she was walking flatfooted on her hind legs. She walks about 5′ and lays down. She can jump onto coffee table (about 18 inches) and will climb steps about 1 to 2 at a time and then resting before moving on to the next step. However, her climbing appears to be very difficult. She is using the litter box and seems to be doing so just fine (my first effort was to make sure she was urinating and defecating). Our caretaker said she noticed a limp about mid-week. Any thoughts on what her cause might be?

    1. Avatar photoDr. Pete Wedderburn, DVM Post author

      Hi Sue – as the article explains, there are many possible causes, and certainly, even though previous blood tests for diabetes were normal, this diagnosis remains very possible. The only way for you to take this forwards is to go back to your veterinarian for an examination and a discussion, followed by tests such as blood and urine samples. Hopefully this will lead you to a specific diagnosis and you can then sort out appropriate treatment. I hope this helps. Pete


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