IVDD in Dogs (Intervertebral Disc Disease)

What Is IVDD?

Discs are the cushions between the bones of the spine. Each has a tough outer ring and a jelly-like center.¹ Discs wear with age in all dogs. Problems start when a damaged disc pushes into the spinal canal.^2,3 Vets describe two main types:^1,8

• Type I (extrusion): the hardened center of the disc bursts out suddenly. This is typical of short-legged breeds in young to middle-aged dogs. In these breeds, discs can start to break down within the first months of life.
• Type II (protrusion): the disc slowly bulges. This causes gradual, often painless weakness in older, larger dogs, usually over about 7 years old.

A healthy disc can also burst during hard exercise or an accident. This usually bruises the cord without pressing on it, so surgery is rarely needed.^1,14 Most of the damage to the cord comes from swelling and reduced blood flow over the following days, not just the first impact.³

Signs and Stages of IVDD

Signs depend on where the disc is and how hard it hits the cord. Discs in the neck more often cause pain alone. Discs in the middle of the back more often cause back-leg weakness or paralysis.² Signs can worsen or settle over the first 24 to 48 hours.² Vets grade severity, usually on a 5-point scale:^2,15,4

A dog with back pain doesn't always have IVDD, and a dog with IVDD doesn't always show pain.² "Deep pain" is a test your vet does by firmly squeezing a toe and watching for your dog to notice, such as turning or crying. A leg pulling back on its own is only a reflex and doesn't count, so don't try to test this at home.^16,5 Loss of deep pain means a severe injury, because these nerve fibers run deep in the cord and are the last to stop working.³

Breeds at Risk and Causes

Most type I disc disease is driven by genes. A variant of a growth gene (FGF4) on chromosome 12 causes short legs and early disc wear. One copy is enough to raise the risk.^13,2 It's carried by almost all Dachshunds, Beagles, French Bulldogs and Cavalier King Charles Spaniels, and by many Cocker Spaniels and Corgis.¹³ Breeds at highest risk include:^5,1,17

• Dachshunds, especially Miniature and Smooth-haired types^5,6,7
• French Bulldogs, where disc disease made up 45.5% of neurological cases in one study, starting at a median age of about 4¹⁷
• Beagles, Shih Tzus, Lhasa Apsos and Pekingese

Other risk factors:

• Body shape and weight: dogs with longer backs relative to their height, and overweight dogs, were at higher risk.¹⁸
• Exercise: Dachshunds exercised over an hour a day were less likely to have IVDD than those exercised under 30 minutes a day. This was an owner survey, so it doesn't prove cause.⁶

How Vets Diagnose IVDD

Your vet will do a neurological exam to find where the problem is and how severe it is.^16,19 X-rays can show hardened discs, but they can't confirm a disc is pressing on the cord. That needs MRI or CT, which are also used to plan surgery.^2,8 Your vet may refer you to a neurologist, especially if your dog can't walk.²⁰

Treatment: Surgery or Strict Rest

The choice depends mainly on whether your dog can walk and whether it can still feel deep pain.⁴

Source: the 2022 ACVIM consensus statement, which notes that recovery without surgery is slower and less complete.⁴

Surgery

Surgery removes the disc material pressing on the cord. For back discs this is usually a hemilaminectomy; for neck discs it's often a ventral slot.^4,21 The consensus recommends surgery for dogs that can't walk and for all paralyzed dogs that have lost deep pain.⁴ Dogs without deep pain are emergencies. There's no firm deadline, though, and surgery shouldn't be refused just because a dog has been paralyzed for some time.^4,3 Surgeons often also clean out nearby at-risk discs (fenestration) to lower the chance of another episode. The benefit is still debated.^4,22 After surgery, dogs need about 4 weeks of strict confinement, pain relief and bladder care.²

Surgery is expensive. One US specialist practice quotes $10,000 to $15,000 all in, including imaging and therapy. Costs vary widely by region.²³

Strict rest (conservative treatment)

Dogs that can still walk, and dogs whose owners can't afford surgery, can be treated with strict rest and pain relief prescribed by your vet. This usually includes NSAIDs and sometimes opioids or gabapentinoids.^4,9,24 Pain medicine without rest is risky, because a dog that feels better may move too much.^5,2 The basics:^4,2

• Keep your dog in a crate or small pen for at least 4 weeks. Dogs that can't walk then need a longer period of gradually relaxed rest. In one study this lasted 12 weeks, and some dogs only walked again after a month or more.⁹
• Allow out only on a leash to toilet, 3 to 4 times a day, with a sling under the belly if needed. No stairs, jumping or furniture.
• Make sure your dog urinates at least twice a day. If not, call your vet, who can show you how to empty the bladder by hand.
• Return to your vet if your dog gets worse or isn't improving after about 2 weeks.

Not being able to afford surgery doesn't mean a paralyzed dog has to be put to sleep. Many dogs recover with careful rest.^24,9

Recovery and Rehabilitation

Dogs that couldn't walk but still felt deep pain often walk again within about 1 to 2 weeks of surgery, at a median of 7.5 days in one trial. Dogs that had lost deep pain can take weeks to months.^25,9,26 Basic rehabilitation is recommended, such as gentle massage and moving the legs through their range of motion.⁴ In a randomized trial, intensive rehab was no better than basic rehab.^25,27 Some dogs that never regain feeling learn to "spinal walk" using reflexes alone. In one study, 7.1% of dogs without deep pain did this.²⁶

At home, use soft bedding and turn dogs that can't move every few hours to prevent pressure sores. Empty the bladder as your vet shows you, and support walks with a sling or harness. A wheelchair (cart) helps dogs that don't regain walking.¹¹ See urinary incontinence in dogs.

The most serious complication is progressive myelomalacia. Here the spinal cord keeps dying after the injury, which is fatal. It affects roughly 1 in 20 to 1 in 10 dogs that have lost deep pain, and more in some studies.^5,4,26

Recurrence and Prevention

IVDD can come back. Signs return in about 30% to 40% of dogs treated with rest.^5,8 After surgery, new discs rupture in up to about 19% of dogs, and in 44% of French Bulldogs. In one Swiss study, signs came back in over half of French Bulldogs after surgery.^4,12 You can't fully prevent IVDD, but you can reduce risk:

• Keep your dog lean.¹⁸ See overweight dogs.
• Give regular daily exercise.⁶
• If you're choosing a Dachshund puppy, ask about the parents' disc X-ray screening. Screening for hardened discs predicts risk better than the gene test in this breed.^28,7

Ramps and harnesses are often advised. No study has shown that they prevent IVDD.⁶

See also neurological problems in dogs, degenerative myelopathy and stroke and FCE in dogs.

Frequently Asked Questions

Can a dog recover from IVDD without surgery?

Yes, often. Most dogs that can still walk recover with strict rest, and many that can't walk do too.

How long does IVDD recovery take?

From a few days to several months, depending on severity. Strict rest usually lasts at least 4 weeks.

Can a dog die from IVDD?

Rarely. Progressive myelomalacia, a fatal complication, can follow severe injuries.

Is IVDD painful for dogs?

Usually, especially at first. Your vet will prescribe pain relief.

How long do dogs live with IVDD?

No study has measured lifespan after IVDD. Most treated dogs walk again, but some have further episodes and a few with severe injuries don't recover.