Dogs With Weak Hind Legs - What is Happening to Them?

A dog losing strength in their hind legs can have countless causes. Poisoning, neurological problems, systemic issues, trauma, etc. can affect the hind legs and keep the animal from moving normally.

Since there are so many possible diagnoses, a vet visit is essential to start treatment. Below, we offer a rundown of the most common conditions behind this disorder.

Weakness in the hind legs from poisoning

The clinical picture caused by poisoning will depend on the type of toxin, how contact occurred, the amount, and the dog's individual characteristics. Some toxins trigger neurological symptoms.

Notable symptoms include excessive drooling, involuntary muscle movements, or weakness in the hind legs. This is a veterinary emergency, since depending on the factors mentioned, it can be fatal.

Lack of strength from hypothyroidism

Hypothyroidism is a disease that occurs when the thyroid gland doesn't produce enough hormones. An affected dog will show various symptoms, the most common being poor hair growth, hair loss, weight gain, absence of heat cycles, and so on.

This condition has also been linked to myasthenia gravis, a disorder that affects nerve impulse transmission. This causes generalized muscle weakness, especially noticeable in the hind legs. Both diseases need medication.

• Full information on hypothyroidism in dogs

Liver failure

When the liver fails, several toxins build up in the body. This can lead to hepatic encephalopathy, which is inflammation of the brain. Symptoms include lack of coordination, weakness, behavior changes, or excessive drooling.

Treatment involves controlling symptoms, preventing the encephalopathy from recurring as much as possible, and finding the cause behind the liver failure. There are various circumstances that can damage the liver.

• Types of hepatitis in dogs and their symptoms

Brain hemorrhages

When there's intracranial bleeding, whether inside or outside the brain, for example from a hard blow, clots form that press on different areas. The dog will show a reduced level of consciousness, a dilated pupil, and weakness or, directly, paralysis in one or more limbs. This is an emergency.

Encephalitis

Encephalitis is inflammation of the brain, which causes fever, behavior changes, depression, uncoordinated wandering, seizures, or, in more severe cases, coma. This is an emergency, since it can be linked to serious diseases such as distemper, rabies, pseudorabies, or herpesvirus.

Tick paralysis

The saliva of some ticks contains a toxin that affects the nerves, causing weakness and paralysis. The clinical picture starts about a week after the bite. Weakness is progressive and can lead to respiratory arrest. This is an emergency.

• Diseases transmitted by ticks

Botulism

This is a disease that causes paralysis. It's due to the neurotoxins produced by the bacterium Clostridium botulinum. Dogs get infected from eating decomposing carrion or poorly canned food. The prognosis depends on how the disease progresses.

Hypokalemia

This refers to low blood potassium levels. It causes generalized muscle weakness. It can be treated by giving potassium and addressing the cause. There are several possible causes, such as intense vomiting, diuretic use, Cushing's syndrome, or diabetic ketoacidosis, a serious complication of diabetes.

Spinal cord injuries

The spinal cord can be injured from car accidents, falls, or gunshots. This causes symptoms such as pain, weakness, or leg paralysis, loss of sensation in the limbs, stumbling while walking, incontinence, and so on. The dog can't stand on their hind legs. This is an emergency, and the prognosis is guarded.

Slipped discs in the back

More common in small breeds, especially the Dachshund, signs appear between 3 and 6 years old. They can develop gradually or suddenly. Notable signs include pain, reluctance to jump or climb, weakness, limping, wobbling while walking, trembling, and even total paralysis of the hind legs. They require medication and, sometimes, surgery.

Eclampsia, or postpartum paresis

This occurs in female dogs due to low blood calcium levels a few weeks after giving birth. It's more common in small breeds, large litters, malnourished mothers, or those who've taken calcium supplements during pregnancy. The female shows anxiety, rapid breathing, pale mucous membranes, and uncoordinated walking. This is an emergency.

Hypoglycemia

This is low blood glucose. It shows up as depression, wobbling while walking, muscle weakness, and trembling. In severe cases, seizures and even death can occur. This is why it's urgent to see the vet at any of the signs mentioned. It needs treatment, and the cause needs to be found.

How to treat a dog with weak hind legs?

Since weakness in the hind legs has so many possible causes, a proper diagnosis is essential. To achieve this, it's important to explain to the vet how the dog's weakness in the legs presented, and whether we've noticed any other symptoms.

The vet will run the appropriate tests to pinpoint the cause, since only from there can treatment be set up and a prognosis given for how it will progress. This is why seeing the vet clinic at the first symptom is so important — in fact, several of these conditions are genuine emergencies.

Bibliography Carlson and Giffin (2002): Manual práctico de veterinaria canina. Madrid: Editorial el Drac. Martínez and Monaldi (2018): Debilidad episódica de origen neuromuscular en perros. Portal Veterinaria. August 14, 2018.