Welcome to Justanswer! I am Dr. Altman and happy to assist you both today!
I am so very sorry to hear about your Zuma's trembling. My primary concern is an injury to the back back when chasing the kitty. This can cause rear limb weakness therefore results in the trembling you are seeing now.
Here is more information on this condition:
Ideal is to have your veterinarian evaluate your dog to definitively diagnose the problem versus a possible orthopedic issues with his back legs and start on appropriate medication to control the discomfort. Until you are able to do this please restrict activity (which often they are already doing themselves but that means no steps/ stairs and only carrying to go potty) and rotating warm and cool compresses on the back in ten minute intervals to reduce pain and increase blood flow.
You can also do light circular massage up and down the back to stimulate blood flow if this is not too painful and will allow it.
To assist and pick your dog up to help him into the care please use one hand between front legs and then scooping behind back legs to avoid pressure in the middle of the back.
Please let me know if you have any additional questions I can assist with. I hope you are able to get your little one comfortable soon, truly.
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