Sudden-onset paraplegia: what canine disc disease looks like

The most common cause of sudden-onset paraplegia in dogs is disc disease in the middle region of the spinal column. This area is known as the thoracolumbar region, because it encompasses the spinal column of the thorax and lower back.

This condition is more common in dog breeds characterised by shorter legs and a longer body, known as chondrodystrophic breeds.

Chondrodystrophic breeds include dachshunds, French bulldogs, corgis, basset hounds and beagles, among others.

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These breeds carry a gene that accelerates degeneration of discs - structures that act as cushions between the bony segments of the spine.

With thoracolumbar disc disease, part of the disc is forced out or extruded, where it can impinge upon the spinal cord and nerve roots.

Clinical signs of thoracolumbar disc extrusion depend on the exact location and extent of compression of these structures.

Signs related to pain include yelping or vocalising, reluctance to jump, abnormal posture, or a tense abdomen.

Signs related to spinal cord or nerve compression can range in severity from mild weakness and reduced coordination of the hind legs, to dragging one or both hindlimbs, bearing weight on the knuckle of the limbs, or being unable to stand and walk.

Some dogs lose the ability to urinate, or to fully empty their bladder, which can lead to urinary leakage.

Because this is a painful condition that can progress, it is important to seek veterinary attention as soon as possible, as Billie's owners had done.

Diagnosis is made through a combination of physical examination and imaging. Plain x-rays may be helpful, but further imaging is often required.

This can include myelography (injection of a dye around the spinal cord to highlight the affected area), or advanced imaging like CT and MRI.

Treatment depends on the severity and progression of disease. Affected dogs that are able to walk are typically treated with a combination of pain relief, anti-inflammatories, and "rest".

Currently, the recommendation is at least four weeks of restricted activity to allow the disc to heal. This should include confinement to a small area, such as a crate, or a small room without furniture (so dogs cannot jump on/off furniture), with regular, short toilet walks.

Dogs should not be walked off lead during this time, nor should they jump in/out of cars, and they should not not be allowed to use stairs, but carried instead.

For active dogs, this period of confinement can be tough. Some of these dogs may benefit from medications to reduce anxiety.

In severely affected dogs (for example, those with complete paralysis like Billie), where clinical signs worsen, or where pain continues despite treatment, surgery may be recommended.

The aim of surgery is to remove extruded disc material and decompress the spine. This is usually performed by surgical specialists in a setting where 24-hour care can be provided.

Following surgery, dogs should be confined in recovery, and may require pain relief for up to six weeks.

Billie underwent surgery and spent a few days in hospital before being discharged home with instructions for strict rest.

He has a few more weeks of rest ahead of him, but the good news is that he is now walking again.

Dr Anne Quain is a lecturer at the Sydney School of Veterinary Science and a practising veterinarian.