Hind Leg Weakness in Dogs With Cushing's Disease

Name: Hind Leg Weakness in Dogs With Cushing's Disease
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-02

Hind leg weakness in dogs with Cushing's disease happens because chronically high cortisol breaks down muscle, especially in the hindquarters, and it often shows up as trouble rising, wobbling, or a hind leg collapse after walks. The good news is that this weakness is usually tied to the hormone problem itself, so controlling cortisol often improves strength. This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

Cushing's disease (hyperadrenocorticism) is a common endocrine disease in adult and older dogs caused by chronic excess cortisol [1].
Excess cortisol causes muscle wasting and weakness, a condition called hyperadrenocorticoid myopathy or Cushing myopathy [2].
Most cases (85% to 90%) come from a pituitary gland tumor, with 10% to 15% from an adrenal gland tumor [1].
Weakness often improves once cortisol is controlled, but muscle loss can take weeks to months to reverse.
Sudden collapse, inability to stand, or loss of bladder control is not typical Cushing's weakness and needs urgent care.

What Is Cushing's Disease in Plain Words

Cushing's disease, also called hyperadrenocorticism, is a common endocrine disease in adult and aged dogs. The signs come mainly from chronic excess of the hormone cortisol [1]. Cortisol is a normal stress hormone, but when the body makes too much of it for months or years, it starts damaging tissues, including skeletal muscle.

The most common cause, about 85% to 90% of cases, is a tumor in the pituitary gland. That tumor produces a hormone that triggers the adrenal glands to overgrow and release too much cortisol. A less common cause, about 10% to 15% of cases, is a tumor in the adrenal glands themselves [1]. Long-term use of corticosteroid drugs can also cause the same signs [1].

For pituitary-based disease, veterinarians use the term Cushing disease specifically [3]. You may also hear "pituitary-dependent hyperadrenocorticism." If you want to understand the difference between the pituitary and adrenal forms, see Cushings Disease in Dogs: Pituitary vs Adrenal Hyperadrenocorticism Guide.

Why Cushing's Dogs Get Weak Back Legs

The muscle-wasting problem

High cortisol does two things to muscle. It speeds up protein breakdown and slows down protein building. Over time, muscle fibers shrink, and the dog loses strength and mass. In dogs, this is called hyperadrenocorticoid myopathy, or Cushing myopathy [2]. Any dog with natural or steroid-induced hyperadrenocorticism can develop it [2].

The hind legs often show it first. Those are large muscle groups that carry a lot of the dog's weight, so even mild wasting becomes visible as a swaying walk, a wide stance, or trouble jumping onto the couch.

Muscle stiffness and cramping

Some Cushing's dogs develop a muscle disorder called myotonia or pseudomyotonia. This causes muscle stiffness, weakness, atrophy, and sometimes contractures that can severely limit quality of life [4]. A 2024 multi-institutional study found this disorder is rare and most commonly occurs in adult dogs with chronic steroid exposure from pituitary-dependent Cushing's disease. No cases of adrenal-dependent disease were found in that group [4].

Other reasons a Cushing's dog may seem weak

Weakness is not always purely muscular. Cushing's disease can affect the heart and circulation. A 2026 pilot study found that dogs with hyperadrenocorticism and myxomatous mitral valve disease had higher urinary normetanephrine-to-creatinine ratios than healthy dogs and dogs with valve disease alone, suggesting extra stress on the cardiovascular system [5]. That can add to exercise intolerance.

Low blood sugar is another possibility. One case report described a dog with recurrent hind limb weakness and episodic collapse that turned out to have severe hypoglycemia from a liver mass, with a blood glucose of 26 mg/dL [6]. This is not a typical Cushing's cause, but it shows why weakness always deserves a full workup.

Signs Owners Notice

Cushing's disease has a long list of signs, and muscle weakness is one of them [3]. Watch for:

Trouble rising from a lying position, especially on smooth floors
A wobbly, swaying, or "drunk" hind end gait
Hind leg collapse after exercise or stairs
Reluctance to jump, climb, or go for normal walks
Visible thinning of the thigh muscles
A pot-bellied appearance from a sagging abdominal wall
Increased thirst and urination
Hair loss, thin skin, or a dull coat
Panting, restlessness, or a ravenous appetite

Behavior changes can show up too. Some dogs become irritable, anxious, or withdrawn. If that sounds familiar, see Cushing Disease Dog Behavior Problems.

Keep in mind that hind leg weakness has many causes. Degenerative myelopathy and disc herniation are common look-alikes, and they are covered in Why Is My Dog dragging hind legs? Degenerative Myelopathy and Disc Herniation. Front leg limping is a different problem with different causes, described in Dog Has Limp Front Leg.

Causes and Risk Factors

Factor	What it means for your dog
Pituitary tumor	Causes 85% to 90% of cases, drives most muscle weakness [1]
Adrenal tumor	Causes 10% to 15% of cases [1]
Steroid medications	Long-term use can cause the same signs [1]
Age	Disease is most common in adult and aged dogs [1]
Breed	Some breeds are overrepresented, ask your vet about your dog's risk
Chronicity	Longer exposure to high cortisol means more muscle loss [2]

The single biggest risk factor is time. The longer cortisol stays high, the more muscle your dog loses. That is why early diagnosis matters.

How It Is Diagnosed

Your veterinarian starts with a history and physical exam, then confirms hyperadrenocorticism with lab testing. Screening and diagnostic tests include the urine cortisol-to-creatinine ratio, the ACTH stimulation test, and the low-dose dexamethasone suppression test [3].

For the muscle problem specifically, diagnosis is based on seeing clinical signs of myopathy in a dog known to have hyperadrenocorticism. Affected dogs might also have elevated serum CK activity and abnormal electromyography and muscle biopsy findings. Subclinical myopathy has been diagnosed in dogs with hyperadrenocorticism and can also occur in atypical cases [2].

In practice, most vets do not biopsy muscle. They treat the hormone problem and watch whether strength returns. If weakness worsens or does not fit the Cushing's picture, advanced imaging such as MRI may be needed to rule out spinal disease. One case report described a dog with progressive pelvic limb weakness that turned out to be a spinal fungal granuloma, found on MRI after a T3-L3 myelopathy was suspected [7]. Spinal nerve sheath tumors are another possibility, and they often cause chronic pain, lameness, and paresis that resist medical treatment [8].

Treatment Options

Treatment targets cortisol, because that is the root of the muscle damage.

Medical treatment

Most dogs are managed with daily medication that lowers cortisol production. Your veterinarian calculates the dose from your dog's weight, test results, and overall health, then adjusts it based on follow-up testing. Never change the dose on your own.

Surgery

Surgery can cure adrenal tumors by removing the affected gland. Pituitary tumors are usually not removed surgically in dogs, though radiation is an option for some cases [3].

Physical rehabilitation

A 2024 study noted that treatment strategies for Cushing's-related muscle disorders include polypharmacy and physical rehabilitation [4]. Rehab can mean controlled leash walks, balance exercises, and assisted standing. Ask your vet for a referral to a certified rehabilitation practitioner.

Support at home

Non-slip rugs or mats on hard floors
A harness with a rear lift handle for stairs and car rides
Raised food and water bowls if your dog struggles to bend down
Shorter, more frequent walks instead of one long outing
Ramps instead of stairs where possible

Recovery, Outlook, and Long-Term Management

Muscle recovery is slow. Cortisol control can start within days to weeks, but rebuilding lost muscle takes longer, often several weeks to months. Some dogs regain most of their strength. Others keep a mild wobble, especially if they were weak for a long time before diagnosis.

Expect lifelong monitoring. Your vet will recheck bloodwork and hormone tests on a schedule to keep cortisol in a safe range. Too little cortisol from overtreatment causes its own serious problems, so the dose needs regular review.

Watch for other conditions that can appear alongside Cushing's. The 2026 cardiac study found that dogs with both hyperadrenocorticism and mitral valve disease showed signs of cardiac remodeling and higher catecholamine markers [5]. If your dog tires easily or coughs, mention it at your next visit.

Weight matters too. Extra pounds load already weak hind legs. Ask your vet for a target weight and a measured feeding plan.

Prevention

You cannot prevent a pituitary or adrenal tumor. What you can do is reduce the risk from steroids and catch the disease early.

Use corticosteroid medications only as long as your vet advises, and ask about tapering.
Never give human steroid creams or pills to your dog without veterinary guidance.
Book annual or twice-yearly wellness exams for middle-aged and senior dogs.
Report increased thirst, urination, appetite, or panting right away.
Keep your dog lean and active to protect muscle mass.

Limitations and When to Contact a Veterinarian

Weakness in a Cushing's dog is not always caused by Cushing's. Individual cases need a veterinarian to sort out what is happening.

Call an emergency clinic now if your dog:

Cannot stand or walk at all
Collapses repeatedly or loses consciousness
Cannot urinate or defecates without awareness
Has trouble breathing or gums that look pale or blue
Has a seizure or sudden severe pain

Call your veterinarian the same day if your dog:

Suddenly gets much weaker than usual
Drags the tops of the hind paws or scrapes them
Shows new front leg lameness or limping
Stops eating or drinking
Vomits repeatedly or seems dull and depressed

Book a routine visit if your dog:

Slowly loses hind leg strength over weeks
Has more trouble on stairs or slick floors
Seems stiff after rest

Frequently Asked Questions

Will my Cushing's dog walk normally again?

Many dogs improve once cortisol is controlled, but the degree of recovery varies. Muscle rebuilding takes weeks to months, and some dogs keep a mild weakness. Your veterinarian can track progress with exams and bloodwork.

Is hind leg weakness in Cushing's dogs painful?

The muscle wasting itself is usually not painful. Some dogs with Cushing-related myotonia have stiffness and cramping that can be uncomfortable [4]. If your dog yelps, guards the back, or refuses to move, that points to pain and needs a same-day call.

Can Cushing's disease cause sudden hind leg collapse?

Sudden collapse is not the typical pattern of Cushing's muscle weakness, which usually develops slowly. A case report linked recurrent hind limb weakness and episodic collapse to severe hypoglycemia from a liver mass [6]. Treat sudden collapse as an emergency.

Does treatment stop the muscle wasting?

Treatment lowers cortisol, which removes the driver of muscle breakdown. Many dogs stop losing muscle and start regaining some strength. Full recovery depends on how long the weakness lasted and how much muscle was lost.

Should I give my dog steroids to help the weakness?

No. Steroids make Cushing's myopathy worse, not better. All reported cases of hyperadrenocorticoid myopathy involved either pituitary-dependent hyperadrenocorticism or dogs receiving exogenous steroids [2]. Only give steroids if your veterinarian prescribes them for a specific reason.

References

Disorders of the Adrenal Glands in Dogs - Dog Owners. Merck Veterinary Manual.
Hyperadrenocorticoid Myopathy in Dogs - Musculoskeletal System. Merck Veterinary Manual.
Cushing Disease (Pituitary-Dependent Hyperadrenocorticism) in Animals - Endocrine System. Merck Veterinary Manual.
Cushing's Myopathy in Dogs: Prevalence, Clinical Abnormalities, and Response to Treatment. Animals : an open access journal from MDPI, 2024.
Catecholamine-associated left ventricular hypertrophy in dogs with hyperadrenocorticism and myxomatous mitral valve disease: a prospective pilot study. Journal of veterinary science, 2026.
Resolution of Recurrent Severe Hypoglycemia After Surgical Excision of a Primary Hepatic Neoplasm of Uncertain Histogenesis in a Dog: A Case Report. Veterinary sciences, 2026.
Case Report: Spinal intramedullary fungal granuloma: clinical findings, surgery, and outcome in a dog. Frontiers in veterinary science, 2026.
Canine spinal peripheral nerve sheath tumours in 18 dogs (2014-2023): surgical management and long-term outcomes. Frontiers in veterinary science, 2025.