Yes, dogs can suffer from bad backs just as we can. Degenerative spinal disc disease is one such condition where the human and canine symptoms and treatment are remarkably similar.
Intervertebral or degenerative disc disease is the formal name describing the bulging (herniation) of the cushioning discs between the vertebrae of the spinal column – in humans, this is often called ‘slipped discs’. Discs are the fibrocartilaginous shock absorbers of the spine and when they bulge out into the spinal cord space, they press on the nerves running through the spinal cord and cause pain, damage to nerves and, potentially, paralysis.
Small to medium-sized, elongated dog breeds are the most susceptible, including Dachshunds, Beagles, Basset Hounds, Lhasa Apso, Pekingese and Shih Tzus. Most affected dogs are middle-aged, from five years old, but some disc ruptures can occur in much younger dogs.
Clinical signs vary depending on the location along the spine of the ruptured disc(s). Affected dogs – often suddenly – will be in severe pain and may cry or appear anxious. They are usually reluctant to move and unwilling to climb steps or jump, may be weak in the hind legs, lose control of their bladder and/or bowel, and generally display stiffness, muscle spasm and pain over the neck and/or back.
Degeneration of spinal discs usually takes place over a period of time before the actual herniation occurs. Sometimes dogs will have minor symptoms and lie around resting without their owners being particularly aware there is a problem. In other cases, the rupture is acute and in the most severe cases, dogs can go from normal walking to paralysis in a matter of hours.
On the left is diagram of a normal spine with the fibrocartilaginous intervertebral discs shown in blue. The right hand diagram illustrates what happens when a disc ruptures or herniates - the disc bulges into the spinal cord space placing severe pressure on the nerves of the spinal cord.
An initial tentative diagnosis of disc disease may be based on a neurological examination, the dog's history of neck or back pain, uncoordinated walking, or paralysis, and if the affected pet is one of the breeds most vulnerable to disc disease.
Plain x-rays are the first step and these can show changes in the bony spine, including narrowing of the spaces between the vertebrae where the symptoms are most noticeable - refer to the x-ray above. Depending on the severity of the condition, specialist veterinary imaging diagnostics may be recommended including myelography (injecting a dye into the spine) or an MRI or CT scan. These will be undertaken should the dog progress to surgery.
Other possible diagnoses that can cause similar clinical signs include cancers of the bone or other tissues of the spinal column, injury and trauma (for example, car accidents), infection and inflammation (sometimes caused by migrating grass seeds) and specific diseases such as degenerative lumbosacral stenosis – a progressive disorder of the vertebrae in the lower back most commonly seen in large breeds of dogs, especially German Shepherds.
Treatment varies significantly depending on the severity of the symptoms and damage to the spinal cord. Dogs with mild signs are treated conservatively with strict cage rest, steroids or anti-inflammatories, and pain relief. Return to normal health varies, but it’s essential the pet is kept restricted as recurrence is reasonably common – it’s estimated that signs recur in 30 to 40% of cases.
In acute cases, when the dog is paralysed, has lost pain sensation or is incontinent and not responding to conservative treatment, specialist surgery to remove a portion of the bony vertebrae over the affected spinal cord (laminectomy) must be considered and undertaken promptly. This relieves the pressure of the bulging discs on the spinal nerves and gives the dog the best chance of recovery. If surgery is delayed for more than 48 hours after the pet can no longer feel pain, the chances of recovery decrease.
Post-surgery, pets will require constant care for a variable time, depending on the severity of their disc disease – owners, with the support of their vet, become very important in the healing process.
Prevention and ongoing management
Owners need to be aware if their pet is one of the breeds vulnerable to disc disease, or a crossbred with a low, elongated body shape. Using a harness when walking, rather than a lead and collar, keeps pressure off the neck, and if at all possible, it’s essential to avoid the need for a dog to climb up and down stairs regularly (consider a ramp), or to jump up into a car or onto a bed or sofa. Managing a pet’s weight is also critical – the more weight a pet carries, the more the pressure on the spine.
These management techniques are especially important for dogs that have recovered from a bout of intervertebral disc disease.