Masticatory Muscle Myositis in Dogs

Category: Muscle
Breeds documented: 1
Published sources: 3

Overview

An abnormal immune response can inflame the muscles that move the jaw. This may cause swelling, pain, and difficulty opening the mouth. Over time, affected muscles can shrink and develop scar tissue, leaving the jaw less able to move. Some dogs lose weight or struggle to eat. The condition mainly affects the jaw muscles rather than the limb muscles.

Signs to watch for

Swelling around the jaw or sides of the head
Pain around the jaw
Difficulty opening the mouth
Loss of muscle around the head
Reduced appetite or weight loss

Most affected dogs are young adults.

When to get help Arrange a vet visit promptly for jaw pain, swelling, or difficulty opening the mouth.

Diagnosis and tests

Vets use a blood test for antibodies against type 2M fibers, which are found in the jaw muscles. A muscle biopsy, a small tissue sample examined under a microscope, can show damage and scarring. That information also helps the vet judge how much jaw movement may recover.

Breeds with documented risk

1 breed

By breed size

1 Large

AzawakhLarge · Hound Group

Inheritance

Not yet known
None of the sources we use states how this is inherited in dogs yet.

We've gathered what published sources say about this condition, so you can talk it through with your vet. It isn't veterinary advice: you and your vet know your dog best.