IVDD Stages in Dogs Explained for Owners

Why stage language can be confusing

A stage describes findings from a veterinary neurologic exam. Numbering can differ between sources; the five stages below match the IVDD Guide. Write down your veterinarian's exact wording rather than assigning a stage from what you see at home.

Compare stages 1–5

The key distinctions are independent walking, voluntary limb movement, and the veterinarian’s assessment of deep pain perception. See Langford Vets’ grade comparison (page 3).

• Stage 1 — Pain only, walking normally. Back or neck pain is present, but the veterinary team has not identified weakness or other neurologic deficits.
• Stage 2 — Walking but weak or uncoordinated. The dog can still walk independently, but may wobble, cross the legs, scuff paws, or knuckle.
• Stage 3 — Unable to walk independently, with voluntary limb movement. The dog can move the affected limbs but cannot take functional steps without help.
• Stage 4 — Paralyzed, deep pain present. There is no voluntary movement in the affected limbs, but a veterinarian has confirmed deep pain perception.
• Stage 5 — Paralyzed, deep pain absent. There is no voluntary movement in the affected limbs, and a veterinarian has determined that deep pain perception is absent.

What the number cannot tell you

Deep pain perception is a clinical finding, not an owner test. Do not pinch toes or try to test pain sensation at home. Bladder function, pain, disc location, imaging, and the speed of deterioration also matter when the veterinary team chooses treatment.

Neck disease may affect any of the four limbs; back disease typically affects the hind limbs. Tell the clinic which limbs changed. An improving gait or better comfort does not by itself end prescribed activity restrictions.

See VCA on neck-disc signs and the ACVS overview of neurologic signs and aftercare.

How to track stage-related changes without overreaching

Good tracking separates observation from interpretation. A note such as 'stood for five seconds with sling support' is more useful than 'stage improved.' A note such as 'could not posture to pee tonight' is more useful than trying to decide whether a new diagnosis applies.

Use the same simple categories every day: pain comfort, appetite, potty, medication timing, standing, walking, paw placement, tail movement if your vet asked about it, and any accidents or trouble urinating. Consistency helps your care team compare today with yesterday.