Head concussions in dogs may be something dog owners worry about especially when they witness their dogs hitting their heads on a hard surface. Perhaps your dog hit is head against the table or perhaps he slammed against the glass door at full speed. Among humans, head concussions are a big concern that can quickly turn life threatening if not tackled in time, but what about dogs? Can dogs suffer from a head concussion as it happens in humans? Veterinarian Dr. Ivana Crnec provides some information about head concussions in dogs and their symptoms and treatment.
A Lesson in Anatomy
The brain, together with the spinal cord, is part of the central nervous system. The brain is the source of your dog’s consciousness and intelligence, and enables your dog to experience and communicate emotions. In addition, the brain controls almost all bodily processes, from sensory perception to regulation of basic functions such as appetite and sleep.
To carry out all these activities, the brain’s billions of cells are communicating with every living cell in the body through nerves and chemicals called neurotransmitters. Due to its delicate structure and vital role, the brain is protected by a bony box known as the "skull."
Can dogs get head concussions? Although dogs have thicker skulls than humans, they are still a risk of head and brain injuries. The most common form of head trauma in dogs is a concussion. A concussion is very serious as it kills brain cells.
The signs and symptoms of concussions in dogs are similar to those witnessed in humans. However, since dogs cannot explain how they feel and what they are experiencing, diagnosing head concussions in dogs is much tougher than in humans.
Another difference is the medical terminology. The term concussion belongs to human medicine. Veterinary professionals prefer the term traumatic brain injury (TBI). (For sake of clarity, the term concussion will be utilized throughout this article.)
Concussions in Dogs
What are the causes of head concussions in dogs? The most common causes of head trauma and subsequent concussion in dogs are: car accidents, falling from a significant height, running into hard objects, blunt blows to the dog's head an dog fights.
There are also several risk factors to consider. The biggest risk factor for head trauma in a dog is unsupervised roaming that can potentially result in either accidental or intentional trauma. It should be noted that, due to their open fontanels, puppies are particularly susceptible to head concussions.
In head traumas, the brain may be seriously damaged even though the skull is intact. If the head is struck on one side, the brain can be bruised as it is shaken within the skull. If the skull is fractured, fragments of bone may penetrate the brain tissue causing major bleeding and damage.
Concussions are usually followed by two potentially life-threatening complications: brain bleeding, which occurs when the accumulation of blood increases the pressure inside the skull, thus worsening he damage and brain swelling, which takes place when the increased volume of the brain makes it too large for the skull, thus causing additional pressure and further damage.
Both complications are considered a medical emergency and require immediate veterinary attention. If left untreated, or if the treatment is delayed, they can lead to permanent brain damage or even death.
Signs of Brain Damage in Dogs
Brain damage can cause changes in a dog’s behavior or physical abilities. The most common clinical signs include:
- Lethargic or depressed appearance
- Anisocoria – differently sized pupils
- Abnormally dilated or constricted pupils
- Nystagmus – rapid, unusual and involuntary rhythmic eyeball movement, often described as "jerky" (in almost all cases both eyeballs move together)
- Trouble standing, walking or keeping balance
- Seizures, convulsions or fits
- Ataxia – lack of muscle coordination
- Head tilt/ head pressing
- Stupor – the dog is unconscious but can be temporarily aroused before falling back into stupor
- Coma – the dog is unconscious and cannot be aroused.
It is worth mentioning that the symptoms depend on which region of the brain has been injured. For example, an injury to the cerebrum may cause changes in the mental status or vision, whereas cerebellar injuries often cause ataxia, abnormal head tilt and nystgmus. The most dramatic behavior changes involve seizures, stupor and coma. Paralysis or paresis may result from injury to the brain or to the spinal cord.
Handling a Dog With a Head Trauma
You need to take a great care if handling a dog that has suffered a head trauma. To successfully manage the situation and prevent further damage it is important to respect the following steps:
- Be as quiet and gentle as possible, and talk soothingly, because any sensory stimulation can trigger pain, fear and seizures.
- In temperate or cool weather, cover the dog with a blanket.
- Asses the dog’s control over its own body. Pinch the skin between the toes on each leg to check limb movement. Lack of pain sensations indicates spine or nerve damage. Are the eyes moving jerkily, or are the pupils differently sized?
- Check for and stabilize fractures.
- Carefully move the dog onto a stretcher, keeping the head higher than the body, and transport the dog immediately to a veterinary clinic.
At the Vet's Office
The diagnostic procedure begins with a general physical examination. If the vet suspects from its signs that your dog has a brain damage he/she will perform neurological exam. The neurological exam consists of specific tests such as:
- Observing the dog’s head posture
- Observing the dog's coordination
- Observing a dog's ability to walk in a circle, clockwise and counter clockwise
- Observing a dog's stance and gait
- Checking for a menace response (response to a visual threat)
- Checking the dog's facial expression and symmetry.
The vet may also shine a light into the dog’s eyes to check pupil light reflex and symmetry, and will also look for nystagmus. These tests help pinpoint the site and extent of possible nervous system damage.
The exact extent of brain damage can only be assessed using special techniques such as electroencephalogram (EEG), brainstem auditory evoked response (BAER), X-rays, CT and MRI scans.
The treatment for concussions in dogs depends on 3 important factors: the cause of the trauma, the severity of the trauma and the location of the damage. While minor concussions can be self-limiting and require just rest and observation, severe cases cannot be resolved without surgical treatment.In order to track the progress of their recovery, dogs with head concussion require close and constant monitoring.
Unfortunately, dogs that experienced head concussion may have some long-term complications, such as: ongoing seizures, drying of the cornea due to decrease blinking frequency, malnourishment due to inability to eat properly and permanent brain damage.
What's the prognosis of dogs with a head concussion? The exact prognosis depends on the extent of damage as well as on how soon proper treatment was initiated. It is not uncommon for the dog’s condition to deteriorate before starting to improve.
In most cases, the prognosis is unpredictable and it usually takes several days until determining the course of events. Some dogs experience full recovery and others, due to overwhelming brain damage, are put to sleep.
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia.
She currently practices as a veterinarian in Bitola and is completing her postgraduate studies in the Pathology of Domestic Carnivores at the Faculty of Veterinary Medicine in Zagreb, Croatia.
Ivana’s research has been published in international journals, and she regularly attends international veterinary conferences.