Help: black lab weakness in back half

I've got a female black lab that just turned 11 this past week. No previous health issues. None at all. Best hunting dog and companion you could ask for. This past weekend out of the blue, she started having weakness in her rear legs, like it is painful to move around. It will come and go. She's her normal happy self for hours at a time then all of a sudden you can tell she's uncomfortable and scared and she'll start shaking. I hunted her a bunch this fall in warm weather so my first thought was, she's got a tick that I cannot find. I took her to the vet Wed and her blood panels came back perfect and naturally while she was there, she was perfectly fine. We've got her on an anti-inflammatory, glucosamine, and some super tick and flea killer that the vet game me during the visit. Basically just treating symptoms right now. She's 100% still there mentally and when she's not having these episodes, still acts like a 3 yr old dog. Runs, takes commands, head up, chest out, eats and drinks and uses the bathroom like normal. It's like 2 completely different dogs. I have noticed that she seems to have these episodes more after she just gets up after laying down and especially first thing in the morning after she's been asleep all night. Could it be a pinched nerve causing the weakness? A pulled muscle that is spasming? I know it can happen with humans.

I know she's getting old but she still has all the drive and intelligence that she had when she was a pup and I refuse to admit she's gotten to be an old timer. Anybody on here had a similar experience or any ideas of what might be going on? Thanks for the help.

With intermittent paresis, it could be a lesion in her lumbar spine. May show up on a radiograph, may not. Unfortunately, probably the only 100% definitive diagnosis you will get would be a neurology referral to Auburn, where there would most likely want to do MRI. Probably looking at $2-3k just for diagnostics.

Osteoarthritis can also show some weird signs that make you think more nefarious causes. Coincidentally it tends to flare up after extended periods of rest. I would cage rest her for a few days and gradually start exercise again. If no improvement, I'd see about getting some spine and pelvis rads done.

Thanks for the input Odo. She's still really slow in the mornings but seems to be pepping back up to her normal self once she gets up and moving around. Will the NSAIDs she's currently taking help with the inflammation? This morning is day 3 on them and has been the best morning she's had in the past 4 days by far. She was tremoring when she first tried to get up this morning but eventually calmed down and everything was fine after that. It's almost like her hip joints have to warm up before she can move around good. Since then, she's been following my wife and daughter room to room in the house which is what she would normally do. Last few days she would just lay back down with no interest in moving around. I'm still trying to keep her movements to a minimum right now. Also trying to keep her off the hardwood floor and on either carpet or rugs so she's not slipping and straining anything at this point.

Yes, NSAID are for the inflammation. I'd stay the course and see how she responds. At her age and signalment, daily NSAIDS for the remainder of her life may be necessary. If she is on the larger side (overweight), cutting back on food and losing weight can really help dogs with bad joints.

Thanks. She's a big, tall dog but she's in good shape for her age. She weighed 75 the other day at the vet. I don't really want to cut her down much more than that. She's definitely feeling better. I had to get her out of her crate this afternoon when I got home. She saw me and was going crazy spinning circles and barking at me. I guess she was trying to tell me she felt better. I opened the crate door and she took off running across the yard full speed and I had to call her back. Now I'm worried about keeping her low key for the next 3-5 days to make sure she heals up and doesn't reaggravate whatever was bothering her and causing the issue. I just find it hard to believe that the meds have made her feel that much better that quick?

It could be a number of things causing it. I would be serious about crate rest for quite a few days or even a couple weeks. If it some some form of injury at her age you need to be careful not to let the dog overdo it when they feel good. Something simple can become chronic pretty easy due to her age.

You should have snapped a lead on her when you opened the crate.