Welcome to Just Answer. I'm so sorry that no other expert answered your question earlier. Your question just showed up on the list of unanswered questions that I have access to and I wanted to help. I hope you will rate my answer rather than the delay. My name is Jane. I have been involved professionally with dogs in the healthcare and behavioral fields for over 20 years. I’ve worked as a Vet Assistant and Behaviorist and have extensive experience in dog reproduction, as a breeder, for even longer than that.. Canine behavioral issues and training are also my specialties. It will be my pleasure to work with you today.
What you describe is a perfect example of arthritis. In older dogs this is usually due to the joints wearing down. In young dogs it can be due to a malformation of the growth plates or congenital defect in the joint, injury or even osteochondrosis (OCD) You can read about OCD here:
It can also occur as a result of an infection such as a tick borne disease or immune system issue. You can read about causes of arthritis in young dogs here:
I would definitely be sure and mention this to your vet at his next check up. Your vet may want to do some imaging to check the joints now rather than wait for the condition to become worse.
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