What Is Paralysis in Dogs?
Paralysis in dogs results from a breakdown in communication among the brain, spinal cord, nerves, and muscles, leading to the inability to move one or more limbs. Typically, nerve receptors receive messages that travel along the spinal cord to the brain. The brain then signals back down the spinal cord to instruct the muscles to move the limb accordingly. Paralysis can manifest as partial (paresis) or complete loss of movement in the legs, affecting either the front legs, hind legs, or all four limbs (tetraplegia).
Front-leg paralysis commonly stems from injuries to nerve roots in the neck and shoulder or from the brachial plexus in the armpit. Hind-leg paralysis usually results from lower back or tailbone injuries or nerve damage between the spinal cord and hind legs (lumbosacral plexus). Any damage to these areas disrupts nerve communication, leading to paralysis or paresis. Notably, nerve trauma stands as the primary cause of leg paralysis in dogs.
When a dog displays abnormal walking patterns or paralysis, it constitutes a medical emergency necessitating immediate examination by a veterinarian or at the nearest veterinary emergency facility. The urgency of the visit is critical since paralysis tends to deteriorate rapidly, diminishing the likelihood of the dog regaining normal bodily function.
Symptoms
Symptoms indicating paralysis in dogs encompass:
- Complete inability to move all four legs
- Inability to mobilize the hind legs, termed as paraplegia
- Difficulty flexing joints in affected limbs
- Partial loss of limb control, known as paresis
- Dragging of the hind legs while moving
- Knuckling or tripping over the paws
- General weakness
- Decrease in muscle mass
- Neck discomfort, evident by holding the head down, lameness in the front legs, and reluctance to move the head or leap
- Spinal or leg pain
- Absence of pain response in the paws
- Limply hanging tail
- Abnormal gait or limping
- Inability to urinate or dribbling urine
- Difficulty in having bowel movements or fecal incontinence
- Constipation
- Presence of Horner’s syndrome on the same side of the body as a paralyzed front leg, characterized by a small pupil, partially closed eyelid, and prominence of the third eyelid.
Causes
There are various causes that can lead to partial or complete paralysis in dogs. Among the most common causes is trauma, often resulting from being hit by a car. While paralysis can affect dogs of any breed and age, certain breeds are more predisposed to medical conditions that can culminate in paralysis. These conditions include:
- Intervertebral disc disease (IVDD): This condition arises from the protrusion of disc material between the spinal bones, leading to compression of the spinal cord. Breeds like Dachshunds, Basset Hounds, and others with elongated backs are particularly susceptible to IVDD.
- Degenerative myelopathy (DM): DM is a genetic disorder causing the deterioration of nerves originating from the spinal cord. Older dogs and breeds like German Shepherds, Boxers, Welsh Corgis, and Chesapeake Bay Retrievers are more prone to this condition.
- Fibrocartilaginous embolism (FCE): FCE, or spinal stroke, occurs when a piece of cartilage from an injured vertebral disc enters the bloodstream, obstructing a spinal artery and impeding blood flow to a section of the spinal cord. While more common in large and giant breeds like Labrador Retrievers and Bernese Mountain Dogs, small breeds such as Miniature Schnauzers and Yorkshire Terriers also face a significant risk.
Other causes of paralysis in dogs encompass:
- Tick paralysis
- Infections like distemper virus, rabies virus, and fungal diseases
- Inflammation or infection of the nervous system, either viral or bacterial
- Muscle inflammation (polymyositis) or nerve inflammation (polyneuritis)
- Blockage of spinal blood vessels or blood flow to the rear legs
- Presence of tumors or cancer in the brain or spinal cord
- Botulism bacterial toxin
- Myasthenia gravis, a disorder inducing severe muscle weakness
- Hypothyroidism, characterized by low thyroid hormone levels
- Genetic abnormalities of the spine or vertebral column
- Prolonged exposure to pesticides or insecticides, especially organophosphates, which can disrupt the nervous system.
Diagnosis
When a dog displays symptoms of paralysis or partial paralysis, veterinarians employ a comprehensive approach to diagnosis. This typically entails a thorough physical examination, which includes an assessment of neurologic reflexes focusing on the limbs, head, legs, and back to identify any signs of pain or abnormal pain response.
Owners are encouraged to provide all relevant information about their dog’s health, including any potential injuries and exposure to ticks or travel. Additionally, veterinarians may conduct various tests such as bloodwork, including complete blood count and chemistry panel, along with urinalysis to detect inflammation, infection, or tick-borne diseases.
While X-rays can initially reveal spinal abnormalities, a more detailed assessment of the brain and spine may require a CT scan or MRI. Veterinarians may also extract cerebrospinal fluid (CSF) to examine for signs of inflammation or infection.
Based on the results of these preliminary tests, veterinarians may recommend muscle or nerve biopsies. Electrical nerve stimulation might be utilized to pinpoint the precise location and extent of a nerve injury, as well as to assess the functionality of the affected nerve.
Accurate identification of the problem’s location is crucial, as closer proximity of a nerve injury to the muscle enhances the likelihood of recovery from paralysis.
Treatment
The treatment required for your dog’s paralysis depends on the underlying cause and may involve hospitalization with intensive care.
During the diagnostic phase, paralyzed dogs often need to be hospitalized as procedures such as spinal X-rays, CT scans, MRI scans, CSF collection, and biopsies necessitate anesthesia.
While nerves can regenerate following an injury, the process is slow (approximately 1 inch per month), and the degree of recovery hinges on accurately pinpointing the nerve injury location. Although veterinarians cannot directly facilitate nerve regeneration, treatments like laser therapy and acupuncture have demonstrated potential in expediting the process.
In cases of swelling, anti-inflammatory medications like carprofen or prednisone may be prescribed. Muscle-relaxing medications such as methocarbamol are also utilized, particularly in dogs with intervertebral disc disease (IVDD). Additionally, pain management is crucial to ensure the comfort of affected dogs, with mild pain typically managed through oral medications and severe pain requiring hospitalization for intravenous (IV) medications.
If your dog experiences urinary issues, such as difficulty urinating or inability to urinate, they may require a urinary catheter to empty their bladder while hospitalized.
For dogs diagnosed with IVDD or specific tumors, surgical intervention may be an option to alleviate pressure on affected areas, potentially restoring limb function.
Recovery and Management
The recovery and management of paralysis in dogs hinge on the underlying cause and the individual prognosis of each case.
The chance of a dog returning to full function varies depending on the cause of paralysis. For instance, Horner’s syndrome indicates a torn nerve root, suggesting recovery from this type of paralysis is unlikely. Conversely, if a dog exhibits voluntary movement of their limb(s), along with pain sensation and spinal reflexes within the initial one to two months, their prognosis for recovery improves.
Dogs unable to urinate will require regular bladder expression at home, a technique that your veterinarian can teach you safely. Utilizing a doggy diaper helps maintain cleanliness in dogs experiencing fecal incontinence.
During the recovery period, it’s essential for paralyzed dogs to wear a protective cone to prevent self-harm. Dogs experiencing pain or lacking sensation in their limb(s) may chew or bite the affected area, making the collar an essential aspect of their recovery.
If there’s no movement or sensation in the affected limb after three to six months, amputation might be the most suitable option to enhance your dog’s quality of life, a decision that your veterinarian can guide you through.
Proper nursing care is crucial for paralyzed dogs to prevent pressure sores. Techniques to ensure their comfort include keeping them on a soft surface, rotating their position, applying heat and massage, and using a sling to assist them in walking.
Using a sling or a soft cloth passed under your dog’s belly and held up on either side of the body can help support their weight while walking. Additionally, specialized wheelchairs may be an option to assist paralyzed dogs in maintaining mobility.
With attentive care provided by a devoted pet parent, paralyzed dogs can adapt well and lead fulfilling, healthy lives despite their condition.
Prevention
- Supervision: Ensuring that your dog is always supervised helps mitigate the risk of injury or trauma that could lead to paralysis.
- Vaccination: Vaccination plays a critical role in preventing viral diseases such as distemper and rabies, both of which can potentially cause paralysis in dogs.
- Tick Prevention: Maintaining year-round tick prevention is essential to safeguard your dog against tick paralysis, a condition caused by certain tick species.
- Genetic Screening: Screening breeding dogs for genetic conditions like myasthenia gravis and degenerative myelopathy can help prevent their offspring from developing paralysis later in life.
By implementing these preventive measures, pet owners can significantly reduce the likelihood of their dogs experiencing paralysis and ensure their long-term health and well-being.