Demystifying Rear Limb Weakness


Dear Friends,
Wow, where did that year go? It’s already 2011—and time for the Winter newsletter from Scout’s House.

In this issue, we unravel the mysteries of “rear limb weakness” in pets. How do veterinarians determine what’s causing it? Is it just old age? And can anything be done to fix it, stop it, or keep it from happening in your pet?

And In The Spotlight this month is Scout’s House Practice Manager Andrea Mocabee, whose unique combination of training and skills as a registered veterinary technician, rehab therapist, and online store manager make her the perfect person to talk to when you’re trying to find the right boot, harness, ramp, or sling for your special needs pet.

Wishing you and your pets a happy—and healthy—New Year!



1101_therapyI’d always been curious why so many pets, dogs especially, get weak rear legs as they age—and sometimes even before they’re old. What causes it? Is it an inevitable result of old age? Over the years, we’ve treated many pets with rear limb weakness (RLW), also called hind end weakness, at Scout’s House, and I’ve learned that any number of disparate medical issues—from diabetes and laryngeal paralysis to bacterial infections and disk disease—may be to blame. But just how your veterinarian determines the cause of your pet’s rear limb weakness is truly a process worthy of Sherlock Holmes.

1101_testingThe first clues are found at the initial appointment, where your veterinarian gathers information about your pet, including history and signalment (age, sex, breed, and so on) to narrow down the possibilities of what is—and what isn’t—causing the problem. It’s hard to believe that something as simple as breed could tip off your veterinarian to the cause of your pet’s weakness, but in fact certain breeds are predisposed to certain illnesses and conditions; Boxers, for example, are prone to degenerative myelopathy (DM), while Dachshunds often suffer from intervertebral disk disease (IVDD). Both diseases can cause rear limb weakness.

And while your veterinarian may be familiar with your pet’s medical history, she might not be familiar with some of your pet’s other histories, such as travel and behavioral, so be sure to mention those as well. If you and your pet recently traveled to an area where Lyme disease is prevalent, for example, your veterinarian will know to look for tick-borne disease as the culprit.

1101_examNext comes the physical exam. By listening to and touching your pet, your veterinarian can learn many things: maybe she detects an abnormal heart rate or rhythm, for instance, or a heart murmur or cough. These symptoms may indicate the RLW is due to cardiac issues, high blood pressure, heartworm disease, or even pneumonia. Or maybe your veterinarian sees signs of pain in your pet when she moves his knee (or stifle) around, indicating a possible ligament tear.

At some point, your veterinarian will also probably do a neurologic exam on your dog or cat. Don’t be surprised, for instance, if she turns your pet’s rear foot over so that the top of the foot is on the ground; although it looks strange, she’s actually checking your pet’s proprioception, or awareness of where her limbs are. Dogs with impaired proprioception may be slow to correct the upside-down foot—or fail to correct it at all—in which case your veterinarian knows to consider neurological abnormalities as the possible cause of the muscular weakness.

A complete neurological workup, including imaging, muscle biopsy, cerebrospinal fluid (CSF) evaluation, or electromyography, may be called for to help your veterinarian get closer to a diagnosis. Specifically, it may pinpoint the origin of the problem, such as in the brain (eg, epilepsy, vestibular disease, drug effects, or a lesion) or spinal cord (eg, Wobblers, DM, or cauda equina syndrome), or somewhere in the peripheral nervous system, whether neuromuscular (eg, feline leukemia virus, myasthenia gravis, or systemic lupus) or polyneuropathy (eg, endocrine disease, diabetes, or botulism).

Finally, your veterinarian also will want to run some blood work and do a urinalysis on your pet. While it may seem strange to do these tests on a pet with weak rear legs, in fact, blood tests and a urinalysis can help veterinarians rule in—or rule out—many possible causes of muscular weakness, including metabolic disturbances, such as organ dysfunction, anemia, or malnutrition, as well as electrolyte abnormalities, including increased or decreased levels of sodium, potassium, calcium, magnesium, or phosphorous in the blood. Each abnormal level of these vital electrolytes can be a clue to the possible culprit, whether it be a urinary tract obstruction or the ingestion of antifreeze.

1101_acupunctureTogether, these efforts will yield important clues to the cause of your pet’s rear limb weakness.  And if your veterinarian is able to pin down the culprit, you may be able to mitigate or even resolve the problem with interventions such as surgery, medication, or rehab therapy and acupuncture.  At Scout’s House, we’ve had remarkable success helping old dogs strengthen their weak rear legs, so don’t give up on your pet just because he’s old.  Work with your veterinarian to find the cause of your pet’s rear limb weakness.  You—and your pet—will be glad you did.




In The Spotlight

1101_spotlightAndrea Mocabee
RVT, Practice Manager

In every business there is one person who seems to be able to do everything. At Scout’s House, that’s Andrea Mocabee, our Practice Manager.

A Registered Veterinary Technician, Andrea joined Scout’s House in 2007 as a Rehab Therapist, working with patients to help them achieve better mobility and functionality despite a variety of illnesses and conditions. The things she learned as a Rehab Therapist—along with her amazing organizational skills and easy way with people—made her the obvious choice when we were looking for someone to manage our growing business.

Today, Andrea is the go-to person for everything Scout’s House. Our clients love her for her masterful scheduling and admin talents, as well as for her winning way with animals when she fills in as a Rehab Therapist. Our online store customers love her for her depth of knowledge about our products and her ability to match the right solution to each pet’s individual needs. And we love her because we couldn’t run this place without her!

Andrea has a Bachelor of Science degree in administration of justice from San Jose State University and an Associate of Science degree in Veterinary Technology from Foothill College. She’s also trained as a police officer, having completed the Police Officers Standards and Training Police Academy in 2001.

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