Why is my senior dog's jaw stiff, head sunken, with a face lump?
There are a couple of things that come to mind when you mention Shrek's symptoms, and I have personal experience with it. Last year, my 12 year old Golden started having trouble opening her jaw, and the muscles around her head and skull atrophied (shrunken and wasted away). She had an inflammatory disorder called masticatory myositis (MM). This is when the immune system attacks the masticatory muscles, leading to pain with opening the mouth and wastage of the muscles of the head. It is a disease that mainly affects large breed dogs. It can be treated with a course of steroids, but prognosis depends on the severity of the disease. In my dog's case, the steroids helped, but it turned out she had cancer as well, and a large lump grew on the back of her head. Unfortunately, there was nothing I could do for her, so I had to let her go peacefully. When you mentioned the growth on Shrek's face, my immediate thought was that he may have a cancerous growth as well as MM. This is a hard decision to make, whether to let him go or not, but my advice would be to have the lump diagnosed first. If it is cancerous, that will help your decision. I would have an appointment made with your vet for Shrek first thing tomorrow so you can discuss the chances he has MM and have the lump diagnosed. The vet can perform a test called a fine needle aspirate on it. To do this, the vet sticks a small needle into the lump to get a sample of it's cells, and examines the cells on a slide under a microscope. It's usually painless to the animal, and relatively quick to perform.
I would be glad to consult with you further on this issue. I work for a home euthanasia service, and face these types of decisions all the time. In addition, having had personal experience with similar symptoms in my dog, I may be able to help you further beyond this answer. If you'd like to consult with me, simply click on the "consult online" button under my answer. I'm sorry Shrek is so sick and you have such a tough decision in front of you :-(
Updated on September 23rd, 2025