The impingement, or pressure of the nerves of the spinal cord, can be due to several causes and can be located in the three parts of the canine vertebral column: neck, back and lumbar area. It is usually more common in older dogs, with osteoarthritis or wear of the intervertebral joints, although dogs that have suffered an accident, blows, overexertion or poor posture can also develop it.
The diagnosis is based on neurological examination and imaging tests and treatment varies depending on the severity of the injury. Keep reading this article on our site to learn more about impingement in dogs, types, symptoms and treatment.
What is a dog impingement?
By impingement we mean the pressure on a nerve by structures adjacent to it, such as bone, cartilage, tendons or muscles. This pressure causes a series of annoying clinical signs for our dog.
The Canine Vertebral Column
The vertebral column of dogs is made up of 30 vertebrae, which are the bones that make up the spine, not including the tail, which It depends on the race and the individual. This column serves as the axis of the body and as the attachment of muscles and bones; and it is flexible because the vertebrae are separated from each other by structures called intervertebral discs.
The spinal column houses within it the spinal cord, which is a part of the nervous system that serves as the axis and connection with the central nervous system (brain). Nerves arise from it in different locations to innervate the muscles of the extremities. There are also two key areas and important for the number of nerve structures: the brachial plexus and the lumbosacral plexus.
Types of impingement in dogs
When we say that a dog has impingement, we refer to impingement at the level of the spine, which can be of three types:
- Cervical impingement: Also called cervical radiculopathy, it occurs in the area of the cervical vertebrae in the neck.
- dorsal impingement: occurs in the dorsal vertebrae of the back between the neck and the lower back. It is usually the least painful and traumatic.
- Lumbar Impingement: It is a fairly common area as it is a place of rotation and daily force. It occurs in the lumbar vertebrae, at the end of our dog's back.
To better understand the different types of impingement in dogs, we recommend you read this other article on Dog Anatomy - External and Internal.
Symptoms of impingement in dogs
The clamping in dogs will cause signs derived from the pressure that is being exerted on the nerve or nerves in question, altering its correct function. In general, impingement in dogs can give rise to the following clinical signs:
- Increasing pain.
- Tingle.
- Numbness of the affected area.
- Weakness in the area.
- Numbness.
- Muscle spasm.
- Joint crunch.
In addition, the impingement is characterized by presenting pain also in the areas where the nerve innervates (arm in the case of cervical impingement or the leg in lumbar impingement), as well as in the area of the damage itself where the nerve root pain occurs (radicular pain).
Over time, impingement can cause a Herniated Disc This is due to the blockage of the vertebra in the same position due to pressure, causes damage to the intervertebral disc that presses on the nerve. This pressure and static posture maintained over time causes the intervertebral disc to fracture the vertebral rings, first causing a protrusion and then a hernia. When severe damage occurs, it can cut off nerve transmission and cause paralysis.
Causes of impingement in dogs
The origin of spinal impingement in dogs can be traced to the following causes:
- Age: the wear of the intervertebral joints in older dogs can make them more fragile and prone to nerve pressure
- Overexertion.
- Bad posture.
- Osteoarthritis: degenerative disease due to the wear and tear of the articular cartilage of a joint. In the case of vertebral osteoarthritis, it can predispose to impingement
- Traumatisms: blows to the spine can cause impingement, as well as other intervertebral disc problems and other soft tissue damage.
For all these reasons, we recommend a regular check-up with the vet.
Diagnosis of impingement in dogs
To diagnose this pathology, the first thing to do is to perform a neurological analysis of the dog, in order to determine the location of the lesion and its consequences at the level of spinal reflexes, strength and mobility. The definitive diagnosis of impingement in dogs is achieved with imaging tests, such as:
- Plain x-ray.
- Contrast radiography.
- CT scan.
- Magnetic resonance.
The last two tests are the best to determine the location of the injury, as well as its degree of involvement and its severity. They are also key when planning the surgical treatment in the most complicated cases, such as herniated discs.
Do not forget that some diseases such as hypothyroidism and diabetes mellitus can affect the peripheral nerves and confuse the diagnosis in certain cases, so ashould always be performed blood analysis in order to rule out these diseases.
Treatment of impingement in dogs
When the degree of impingement is mild, treatment will be conservative with medical therapy with anti-inflammatories, rest and heat in the area. On the other hand, when there are neurological signs but the injury is not very serious, it also usually responds well with anti-inflammatory therapy, but it will be necessary to be very attentive to the evolution and possible complications.
However, when the neurological deficit does not improve and, on the contrary, is getting worse, you should plan the surgery, without waiting too much because if you wait too long, the injury can be irreversible.
The surgery seeks to release the spinal cord and nerve roots from the pressure it is suffering through a surgical intervention, called a laminectomy, to remove part of the affected vertebra or vertebrae and allow the passage of the cord and its decompression. For its part, physiotherapy is a good complement for a better and faster recovery.
