Hi there, I'm Dr. Sara. I'm a licensed veterinarian who works exclusively with dogs and cats. I'm sorry to hear that Sadiebear hasn't been feeling well. I'll do my best to help.
There are a lot of issues that can cause wobbliness or incoordination in the back legs. I won't be able to tell you definitively what is happening with Sadiebear without doing a physical examination in person, but I can tell you what diseases we see most commonly that can cause the symptoms that you're seeing.
By far and away the most common reason for a young otherwise healthy dog to have weakness or paralysis in the back legs (dragging the back legs) would be intervertebral disc disease. This is when one (or multiple) of the discs between the vertebrae become inflamed, swollen, rupture, or slip out of place. This places a varying amount of pressure on the spinal cord, causing it to malfunction. In milder cases, pain is the only symptom. One step more severe causes scuffing of the toes and delayed reflexes. One beyond that is muscle weakness in the legs (back legs only if the disc problem is behind the front legs but in front of the back legs), and the worst possible scenario is full paralysis and loss of pain sensation. In the more severe cases, the sooner they receive veterinary care, the more likely they will be to return to walking with normal function. If the vet suspects IVDD, and they are able to do advanced imaging, an MRI or CT scan are the methods of choice to diagnose these lesions, because the discs and spinal cord do not show up on X-rays. X-rays can be helpful for general information - especially looking for signs of bone fractures or destruction. Treatment for a disc that's compressing the spinal cord would be surgical removal of the disc material from the canal to decompress the cord.
Another potential cause would be FCE, which is a disease in which one of the blood vessels that supplies a portion of the spinal cord becomes blocked, causing a portion of the spinal cord to die and lose function. This again is a diagnosis via advanced imaging like a CT/MRI scan - it can be very difficult to tell from IVDD on a physical examination. Treatment for FCE is mostly supportive and nursing care while we wait to see if and how much function they will recover - it can take weeks to months to know how well they will recover.
Another potential that is less common would be a spinal infection or tumor - while these are far less common, they can cause the same symptoms. They can be diagnosed by advanced imaging, and blood work can also sometimes give us a clue about an infection being present. A spinal tap could also give info on the type of infection if one is present. Even more rare would be immune mediated (autoimmune) inflammatory spinal disease.
If you can, the absolute best thing to do for Sadiebead would be to get her to a veterinary emergency hospital for an exam. IVDD is the most common disease and timely treatment is most important when considering whether she can recover. If you can't get her to an emergency vet ASAP, keep her strictly confined to a bed or crate - do not let her drag her legs around or move about at all, as this can further exacerbate her injury. It's a good idea to line her bed with water absorbent pads in case she urinates or defecates while she's laying in bed. Once he's examined, your vet will have a better idea of what might be causing her issues and lay out your options - whether it be diagnostics like advanced imaging or attempted medical management with time, TLC, anti-inflammatories, and rest.
I hope that this information was helpful to you - please let me know what other questions I can handle.
Please let me know what other questions I can handle for you.
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