What is causing this muscular seizing in my cat?

Question

Background

My cat, Polar, is a very amiable calico. This past January (2016) or so, Polar started having these episodes where suddenly her two right paws would seize up, being pulled towards her torso, and half a beat later she is fine. We thought it would sort itself out. By late February, we started being concerned. These episodes got worse,instead of stumbling, she would fall. When she seized, her right side paws would be yanked tightly against her torso. At this point, there was no affect on her left side. She would fall, two seconds later, she gets up without acknowledging anything happened. In early March, we took her to the vet. He didn't witness any episodes, said it wasn't seizures, and that she was very healthy. By late April, the intensity of the episodes plateaued. They only last 3 or 4 seconds. Her right legs are pulled against her torso, her left legs forcibly extended straight down, and her face clenches. Unfortunately the frequency has increased from 5 per week (Feb) to 1 per hour now (May). I know cats are tough and don't show pain, so I'm not sure how much these episodes hurt. What is really bad is the falling. She falls off of stuff all the time (less than 4 ft high) and hits the ground like a rock because she is in an episode. She has a scab above her eye from one of these falls. Right now we don't have stairs, but we are moving soon to a house with 2 flights. What can I do to fix/alleviate this? If I can't fix it, what would be a sign that I should put her to sleep?

Problem Description

My cat, Polar, goes through episodes where her muscles seize, however they are not seizures. Here is what I can discern about them:

• Triggers: When she wakes up, when she gets up to fast, when she is startled, when she goes from walking to running, when she jumps onto something
• Duration: 3-4 seconds of where the muscles are taut, then 1-2 seconds before she gets up and moves on
• Characteristics: She is consistently contorted in the same way, she does not try to avoid the triggers, she is not defensive afterwards,

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Details

Here are some details about Polar and her life that may or may not be relevant:

• Videos of two episodes are here and here
• Age is at least 9 years. We found her under a shed in the middle of a snow storm 9 years ago, she looked like an older kitten.
• Desexed, front paws are Declawed, lives strictly Indoors and for the past 3 years she has been our only cat (she hates other cats)
• Diet is heathly dry cat food (we switch to a different brand in March to see if that helped) and filtered water
• Medical History is minimal she is probably not up-to-date with shots or anything like that. We've never had any problems with her besides last summer (2015). She would get a scab on her chest from scratching or something and would proceed to go full-on OCD grooming herself trying to get her fur smooth, which would enlarged the wound. She did this several (more than 10 less than 20) times. She also caught a bat in our house (Fall 2014) once. Also the knobs on the back of her ankles on her rear legs are bald because she chews that them regularly.

What I've tried Here is everything we've tried so far:

• Vet: Took her to the vet. She is healthy and not having seizures.
• Diet Change: We changed food brands to see if it would fix it, no discernible effect
• Research: We've tried researching what the problem could be, could not find anything. Every search with muscles/seizing turns up seizures. I'm at the end of my rope on what to look into.
• Networking: We've talked to long-time cat owners, vets/vet assistants that we know and they didn't have any ideas.

Conclusion

We are concerned that when we move next week to a house with stairs, that she could seriously injure herself (we can't block off the stairs from her). Another worry is that this condition could escalate to a point where she would have to be put down for her own good. Any ideas on how to fix/alleviate these episodes? How do I discern when to we should put her to sleep?

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Update

On January 24th 2017, we put Polar to sleep. Within a year of first showing symptoms, she would have episodes as frequently as 10/hour and started having them while sleeping.

Answer 1

I would show those videos to a vet; they may be able figure out what it is once they see it, or at least tell you if she is in pain. The fact that she doesn't avoid the triggers and is relaxed afterward suggests to me that the seizure itself is not painful, although the resulting injuries might be.

Triggers: When she wakes up, when she gets up to fast, when she is startled, when she goes from walking to running, when she jumps onto something

When you move to the new house, I would find a way to restrict her to one floor temporarily. Then, if the vet can reduce the frequency of the episodes I think she might be able to adapt to a multi-story house provided that the only way to get from one floor to another is via normal enclosed stairs. (I.e., not something like a loft where she could just fall off the edge.) She's not super likely to do any of those things that you define as triggers at top of the stairs. Cats prefer to relax in places that aren't in the main traffic flow of the house. And if worse comes to worst and she has a seizure on the stairs, she'll probably only roll down a step or two because cats aren't smooth cylinders.

I'm not making light of the problem; it is scary and there is the potential that she will hurt herself. When I've had animals that acquired disabilities, I was overwhelmed at first, but gradually I figured out little ways to keep them safer and ensure that they enjoyed life. So you probably don't need to make a decision yet; wait and see what happens. Maybe someone who has a one-story house will take her.

If the vet can't reduce the frequency of seizures, and you can't restrict her to one floor permanently, then you may have a difficult decision to make.