Brief Answer:
Probably caused by arthritis: Senile degeneration of the joints.

Detailed Answer:
Hi and thank you so much for this query.

I am so sorry to hear about this joint stiffness and pains that you have reported. I have reviewed your information fully and this si very suggestive of progressive wearing of the joints over the past decades of life. I will recommend regular physical exercises with your trainer to help keep pets joint flexible and reduce the pains. Continue for now with Tylenol as well. Should this persist after trying the above measures or getting worse, seek a medical consultation with a orthopedic surgeon for further evaluation and investigations with imaging tools.

I hope this helps. I wish you well. Feel free to ask for more information and clarifications if need be. Above all, thanks for using our services.

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