Ruptured Discs in Dogs

The anatomy of a dog’s spine is very similar to our own. The many small bones that house the spinal cord (called vertebrae) form a protective cage around the spinal cord, and the discs that exist in between the vertebrae allow for flexibility and protection. It is possible to injure these intervertebral discs and develop clinical signs as a result.

Intervertebral discs are made up of two layers: a fibrous and firm outer layer with a softer pulpy layer in the center that is the consistency of toothpaste. These discs prevent the vertebrae from touching as your dog walks and jumps, as his back moves up and down and twists from side to side. The discs act as shock absorbers so that the spinal cord is further protected.

Discs are located beneath the spinal cord. Due to various factors, intervertebral discs can herniate or “slip,” and because the thinnest part of the disc is at the top, discs tend to herniate upward towards the spinal cord. When this occurs, it puts pressure on the spinal cord. The spinal cord is made up of many nerve fibers and is responsible for sending nerve signals throughout the body. If the cord is pinched by a herniated disc, it will negatively impact these signals or cut them off altogether. This is why severe spinal cord injuries can result in paralysis. Without treatment, paralysis can be permanent.

Most of the time, pain that comes from a ruptured disc can be very acute. This is the case with disc herniations due to trauma such as road traffic accidents, falling from high places, and after vigorous exercise. However, healthy discs are meant to take a lot of pressure from these impacts; therefore, it is suspected that ruptured discs may have already been diseased before the impact occurred.

Dogs can develop degenerative joint disease due to a number of factors, chief among them being genetic influences. Dachshunds, German Shepherd dogs, Dobermans, and Cocker Spaniels are some of the most commonly affected dog breeds. Over time, the stability of the intervertebral discs can weaken due to spontaneous degeneration. This means it is easier for discs to rupture with only mild impact.

Ruptured discs can cause significant pain. Your dog may appear uncomfortable or restless at first, and he may not want to walk for as long as he normally does. He may try to avoid jumping up on furniture or walking up and down stairs. Some dogs might get better after a day or two of rest, but others may continue to feel pain. Also, you may start to see evidence of mobility problems.

Depending on which disc ruptured, your dog may have problems walking on his forelimbs, his hind limbs, or all four limbs. The most common area where discs can herniate is in the middle of the back. When this location is affected, it can cause hind limb weakness or paralysis while the forelimbs may appear normal. If the disc herniation occurs between the cervical vertebrae in the neck, all four limbs may be affected.

If you suspect that your dog has a herniated disc or is having trouble walking, you should take him to his vet right away. The vet can perform a quick neurologic exam to see if the affected disc or disc lesion can be isolated. Sometimes, there is evidence of a herniated disc on x-rays, but because the discs and spinal cord are soft tissue structures, it can be difficult to see the borders of the spinal cord and to see if pressure is being applied.

Some veterinarians can inject a special dye that goes around the spinal cord to see where the herniated disc has occurred. This is called a contrast myelogram. For a more definitive diagnosis, advanced imaging like CT scans and MRI can isolate the disc’s location. The majority of acute limb weakness and paralysis cases are caused by herniated discs and degenerative joint disease, but if imaging is normal, there may be another disease process present like a fibrocartilaginous embolism (resulting in acute spinal cord death) or a blood clot due to circulatory disease.

Treatment will be based on the severity of the disc herniation. Veterinary neurologists classify ruptured discs into five stages. Stage 1 ruptures may improve on their own after a few days. Stage 2 and 3 ruptures can cause moderate to severe pain or partial paralysis and require anti-inflammatories, pain medications, and strict rest. Stage 4 and 5 ruptures are so severe that surgical therapy is necessary. After just 24 to 48 hours, acute paralysis of the affected limb(s) may be permanent. This is why emergency surgery is indicated in severe cases.

The goal of surgery is to open the vertebrae on one side so that the pressure on the spinal cord is relieved. This type of procedure should only be performed by a boarded veterinary neurosurgeon. Once surgery is performed, strict rest is necessary for several weeks, and you will need to assist your dog when he goes outside to the bathroom.

Physical therapy is also an important part of recovery in order to help your pup regain strength in his back and limbs. Swim therapy, acupuncture, cold laser therapy, and passive range of motion exercises may be recommended in some instances. Even dogs who do not undergo surgery may stand to benefit from these integrative techniques. For dogs with permanent paralysis, some can have an improved quality of life when they are fitted for a special kind of wheelchair.

Orthopedic dog beds can assist with recovery from major surgeries. A true orthopedic dog bed aligns the spine and reduces pressure points that exist with other memory-foam dog beds. The alignment of the spine and reduction of pressure points can actually decrease the amount of time it takes to recover from surgery, making it a natural choice for many situations.

Ruptured discs can be very painful and can cause varying degrees of mobility problems. Dogs can start out with mild pain that persists or progresses, so if your pup is showing signs of pain or discomfort, be sure to contact your veterinarian as soon as you can. Acute limb weakness or paralysis may be a medical emergency. If a higher stage disc herniation is suspected, you may need to be referred to a specialty hospital on an emergency basis for urgent surgery. Recovery can take several weeks, but when surgery is performed within the first 24 hours, there are much higher success rates for recovery.