A disc is a cushion of cartilage that sits between the vertebrae and acts as a shock absorber. It is made up of a rim of tough, fibrous connective tissue that surrounds a gel-like center called a nucleus. Although the tissue of the disc is tough, disc rupture is not uncommon in dogs. While disc rupture could happen to just about any dog, some are more susceptible than others. The type of disc rupture affects certain dogs most often as well.
Types of Disc Ruptures in Dogs
When a disc ruptures, a fibrous capsule breaks, allowing the inner nucleus to push out through the opening and impinge on the nerve root or spinal cord. This is called Hansen Type 1. Hansen Type 1 typically occurs in small breeds such as Beagles, Cocker Spaniels, Dachshunds, Pekingese and small mixed breeds. However, Hansen Type 1 disc ruptures are more frequent in Daschunds than all other breeds combined.
Roughly 80 percent of Type 1 ruptured discs occur in the lower back between the last thoracic and the first two lumber vertebrae. The remainder typically occur in the neck. At around two to nine months of age, the capsule will begin to degenerate. Signs of impingement on the spinal cord appear between three-six years of age. With Type 1, there is often a history of mild trauma, such as leaping off a sofa, but even normal movements are sufficient enough to cause a Type 1 disc rupture.
Symptoms of Type 1 disc rupture include:
- Pain
- Crying or whining when patted or handled in the injured area
- Holding the back stiffly
- Refusal to walk up stairs or jump into a car
- Weakness
- Lameness
- Panting and trembling
- Tight abdomen or hunched position
- Wobbly gait
Sudden Type 1 disc rupture can cause also complete hindquarter paralysis.
When the entire disc, surrounded by an unbroken capsule bulges outward, this is called Hansen Type 2. Type 2 typically occurs in larger breeds such as German Shepherds and Labrador Retrievers. Type 2 disc ruptures appear in dogs from five to 12 years of age. The process is gradual so symptoms progress slowly. Type 2 disc ruptures cause pain, which may result in crying or whining when patted or handled in the injured area.
Treatment for Disc Ruptures in Dogs
The type of treatment for your pets disc rupture will depend on how advanced it is. A dog with a sudden onset of symptoms of paralysis must be rushed to the vet. If surgery is performed within 24 hours, this will produce the best outcome. Disc ruptures accompanied by pain or mild paresis (slight paralysis) may improve with rest and medication. When prescribed rest and medication, the dog should be closely confined for two to four weeks to allow the disc to return to its former position. Analgesics will relieve pain and corticosteroids reduce swelling. If the disc rupture is in the neck area, when walking the dog, a chest harness must be used rather than a collar.
In addition to medication and rest, minor disc ruptures may respond to acupuncture and physical therapy. These supplemental treatments may be incorporated into treatment protocols.