TL;DR: Sudden hind limb paralysis in cats is a life-threatening medical emergency often caused by a blood clot, requiring immediate veterinary intervention to manage severe pain and attempt to restore circulation.
What causes sudden hind limb paralysis in cats?
Sudden paralysis in a cat's rear quarters is a distressing event that often indicates a serious underlying cardiovascular or neurological issue. One of the most common causes is Feline Aortic Thromboembolism (FATE), commonly referred to as a saddle thrombus. This occurs when a blood clot lodges in the terminal aorta, suddenly cutting off the blood supply to the hind legs.
Is sudden back leg paralysis a veterinary emergency?
- Sudden paralysis is a critical medical emergency with a high urgency level.
- Cats experiencing this condition are often in significant pain and may exhibit heavy breathing or loud vocalization.
- Check if your cat's back legs are limp, cold to the touch, or if their paw pads appear blue or pale.
- Seek emergency veterinary care immediately, as time is of the essence to manage pain and restore circulation.
How can photos and videos help with my cat's emergency triage?
- Provide a quick video of your cat's movement or a photo of their posture when you call the emergency clinic.
- Visual information allows triage staff to assess the severity of the situation before you arrive.
- Sharing media helps the team differentiate between causes like a spinal injury or a vascular event.
- Advance information ensures the medical team is fully prepared for your cat's specific needs the moment you reach the hospital.
Clinical Context (Merck Veterinary Manual)
Sudden rear leg paralysis in cats can manifest as posterior paresis or paralysis. A common cause is arterial thromboembolism, often associated with underlying cardiomyopathy, leading to focal muscle necrosis and degeneration of the sciatic nerve. Clinical signs include extreme pain, firm gastrocnemius muscles, and potential ability to move legs above the stifles with the tail often unaffected; Doppler ultrasonography helps evaluate blood flow in the distal aorta and femoral arteries for diagnosis. Management involves analgesics, nursing care, treatment of any underlying disease, and anticoagulants like heparin to reduce further thrombus formation. Thrombolytic therapy has not shown improved survival. Neurologic deficits may improve within weeks, but complete recovery can take months, with permanent deficits possible; prognosis is guarded, and euthanasia is common.
Chapter: Neurology, Emergency, Rehabilitation
Source: The Merck Veterinary Manual, 11th Edition (Page 1954)