TL;DR
- Knuckling means walking on the top of the paw, usually a nerve problem, not pain.
- Book a vet exam; call same day for sudden knuckling, dragging, yelping or collapse.
- Protect paws daily, add traction, keep weight lean, and consider harnesses, booties or a wheelchair.
Dog knuckling means the paw curls under so your dog walks on the top of the foot instead of the pad. In degenerative myelopathy, a progressive disease of the spinal cord, this is a nerve problem rather than a sore paw: the dog's nerve fibers are degenerating, so it has trouble sensing and placing its feet normally in a way that arthritic dogs do not, and the resulting incoordination is not painful.1 More on weak and wobbly back legs.
What knuckling looks like at home
The hind paws knuckle or turn under so the dog walks on its knuckles, especially when turning.2 The hind feet seem to scrape the ground when walking, and sometimes the top surface of the feet becomes hairless and irritated from repeated trauma.2 Scuffed toenails on the hind limbs are another common sign.3
You can also gently flip one back paw so it rests knuckled over, then let go. Slow correction, or none, is worth reporting to your vet.
What causes knuckling in older dogs
Intervertebral disc disease, in which the cushioning discs of the spine break down and compress the spinal cord and/or spinal nerves, is a common cause of spinal cord disorders in dogs, especially small breeds such as the dachshund, beagle and Shih Tzu.1 In large breeds, disc degeneration typically occurs after the age of 5 years, with signs that slowly worsen.1 When the damaged disc lies in the neck, the signs come from pressure on the spinal cord or on the nerve roots that branch off it.4
Degenerative myelopathy causes slowly progressive hind limb weakness and paralysis,2 and it typically affects dogs around eight years of age or older.3 Lower back problems matter too: degenerative lumbosacral stenosis, a narrowing at the base of the spine, compresses the nerve roots there, with signs that include difficulty using the hind legs, tail weakness and incontinence.1
Other causes include a fibrocartilaginous embolism, a spinal cord stroke that typically begins after jumping or running and causes a sudden, nonpainful change in the dog's gait; a spinal tumour causing progressively worsening partial paralysis in the hind legs; or infections carried by rickettsia bacteria, such as Rocky Mountain spotted fever and ehrlichiosis, which can lead to swelling in the spinal cord.1
One back leg knuckling, or both
With a spinal cord stroke, weakness and paralysis are generally localised to one side of the body.5 Both back legs knuckling slowly, with no sign of pain, fits the nonpainful incoordination and weakness of the hind limbs seen in dogs usually older than 8 years.1
Signs that mean a vet visit today
Call the same day for sudden knuckling, a dog who cannot stand or bear weight, dragging with loss of bladder or bowel control, yelping, obvious back or neck pain, or rapid worsening over hours. Dogs that become paralysed and have also lost pain sensation are considered an emergency, and the chances of walking again are very low, even with surgery.6 In dogs with severe nerve signs, surgery must be performed promptly to relieve pressure on the spinal cord.1
What the vet will do
The first step is a neurologic examination, a hands-on check of the nerves and reflexes, by a veterinarian.6 X-rays look for other causes such as a disc infection or bony tumours, but MRI or CT is the preferred imaging.67
Protecting the paws and footing now
Check the tops of both back paws daily for raw spots, and keep nails short so they do not catch. Booties can decrease damage to scuffed paws, and rugs, carpets or yoga mats on hardwood or tiled surfaces help a dog with mobility.3 Fit matters: boots and drag socks should stay put without pinching, come off for skin checks, and never be left on all day.
Rehab that keeps back legs working
For degenerative myelopathy, routine physical therapy may delay the progression of the disease, and after a spinal cord stroke, rehabilitation including assisted exercises, muscle stimulation and hydrotherapy on an underwater treadmill can help dogs regain strength and coordination.35 It is important to avoid obesity, so diet and exercise, including walking and swimming, are vital.2 A sling or harness helps with walking and standing.3
When a wheelchair fits into the plan
A cart makes sense once knuckling comes with rear weakness: tiring on walks, sagging hips, back legs folding on turns. Cornell lists considering a wheelchair to support the hind limbs among management steps for progressive hind limb weakness.3 The OldPal Rear Support Dog Wheelchair carries weight through the hips and chest, with the frame set so the back legs hang free or lightly brush the ground, keeping knuckling paws off the pavement. Sizing needs one measurement, rear leg height: see the size guide and fit finder, or email help@oldpalpets.com with a photo.
Frequently asked questions
Is knuckling in dogs serious, or can I wait and see?
Book a vet exam rather than waiting. Dogs with minimal to moderate signs that can still feel pain often recover with a few weeks of rest.1
Can knuckling in dogs be reversed?
Do anti-knuckling devices and braces actually work?
Aids like slings, harnesses, booties and wheelchairs help physically, but they are only management tools, since there is no cure for degenerative myelopathy.3 Use them for defined walk times, check the skin underneath afterwards, and re-measure if your dog's legs are changing shape.
Why is my dog knuckling on only one back paw?
Watch for the second hind leg starting, since degenerative myelopathy often begins in one hind limb and then progresses to involve both.3
My senior dog's back legs are knuckling and getting weaker. What actually helps day to day?
Traction everywhere, short flat walks on grass rather than one long walk, a support harness for stairs, daily paw checks and a lean body weight. The goal is to keep the dog on its feet for as long as possible, and physical therapy has been shown to preserve muscle mass.2
Related guides
- Knuckling with degenerative myelopathy
- Knuckling and IVDD
- Choosing boots for a knuckling dog
- How the paw flip test works
Sources
Sources (7)
- Merck Veterinary Manual. Disorders of the Spinal Column and Cord in Dogs. merckvetmanual.com
- VCA Animal Hospitals. Degenerative Myelopathy in Dogs. vcahospitals.com
- Cornell University College of Veterinary Medicine. Degenerative myelopathy. vet.cornell.edu
- VCA Animal Hospitals. Cervical Intervertebral Disc Disease in Dogs. vcahospitals.com
- VCA Animal Hospitals. Fibrocartilaginous Embolus (FCE) in Dogs. vcahospitals.com
- University of Illinois Veterinary Medicine. Big Dogs, Little Dogs Get Disc Disease. vetmed.illinois.edu
- Cornell University College of Veterinary Medicine. Fibrocartilaginous embolism (FCE) in dogs. vet.cornell.edu
