Hi stranger! Signing up for MypetMD is easy, free and puts the most relevant content at your fingertips.

Get Instant Access To

  • 24/7 alerts for pet-related recalls

  • Your own library of articles, blogs, and favorite pet names

  • Tools designed to keep your pets happy and healthy



or Connect with Facebook

By joining petMD, you agree to the Privacy Policy.

PetMD Seal

Inflamed Chewing Muscles and Eye Muscles in Dogs

ADVERTISEMENT

Focal Inflammatory Myopathy in Dogs

 

The term myopathy is a general clinical term for a disorder of the muscles. Focal inflammatory myopathy affects specific muscle groups, in this case the masticatory muscles, which are the facial muscles involved in chewing, and the extraocular muscles, the group of muscles that are adjacent to the eyeball and that control the movements of the eye.

 

Focal inflammatory myopathy is suspeced to be due to autoantibodies, or antibodies that are known to react against the body's own tissues. Antibodies are proteins found in the blood and which are used by the immune system to identify and destroy foreign invaders, such as bacteria and viruses. In effect, the antibody has crossed signals, mistakenly attacking the body as though reacting to a pathogen. Focal inflammatory myopathy describes a condition in which these autoantibodies begin targeting the muscles of the affected animal.

 

A genetically based familial form has been found to occur in cavalier King Charles spaniels, rottweilers, Dobermans, and samoyeds, in which the masticatory muscles are affected. A similar form, affecting the extraocular muscles, has been seen in golden retrievers.

 

Symptoms and Types

 

Masticatory Muscles

  • Problems with normal jaw movements
  • Inability to pick up a ball
  • Inability to get and keep food into the mouth
  • Jaw pain
  • Muscle swelling
  • Progressive loss of muscle mass

 

Extraocular muscles

  • Swelling around the eye
  • Protrusion of eyeball from the socket

 

Causes

 

Immune-mediated

 

Diagnosis

 

You will need to give your veterinarian a thorough history of your dog's health, including a background history of symptoms. After taking a detailed history, your veterinarian will conduct a complete physical examination on your dog.

 

Your veterinarian will try to open your dog's mouth, which often proves unsuccessful in these patients. In an attempt to induce pain and swelling of the muscles so that the source of the problem is more evident, your veterinarian may attempt to manipulate your dog's jaw muscles. Laboratory tests will include a complete blood count (CBC), biochemistry profile, and urinalysis.

 

The biochemistry profile may indicate higher levels of serum creatine kinase, indicating muscle injury. More specific testing includes taking a muscle tissue sample, especially important in masticatory diseases. This test can help in reaching a confirmatory diagnosis. More advanced testing may include demonstrating the autoantibodies against the muscle fibers. Diagnostic imaging will include X-ray of the jaw bones and ultrasound of the eye orbit to examine the swollen extraocular muscles. Magnetic resonance imaging may also be used to examine the muscle inflammation.

 

 

 

Related Articles

Muscle Tear in Dogs
A normal muscle can be stretched, pinched, or injured directly, resulting in fiber...
READ MORE
Arthritis (Septic) in Dogs
Septic arthritis is a type of inflammation of the joint that is commonly seen after...
READ MORE
Bone Infection in Dogs
Inflammation of the bone or bone marrow most commonly occurs due to bacterial infections,...
READ MORE
  • Lifetime Credits:
  • Today's Credits:
Hurry Before All Seats are Taken!
Enroll
Be an A++ Pet Parent! Take fun & free courses to earn badges & certifications. Choose a course»
Search dog Articles

 

Latest In Dog Nutrition

How Your Overweight Pet Could Benefit from ...
Pet obesity has reached epidemic proportions. Fortunately, there are some things...
READ MORE
Pet Food Ingredients that Promote Longer Life
Pet foods, in order to promote a healthy long life, must be balanced and complete...
READ MORE
Five Life-Lengthening Health Tips for Your ...
Anyone who has ever had a dog or cat wishes just one thing — that he or she has a...
READ MORE
Around the Web
MORE FROM PETMD.COM