Dog stopping on Walks

Question
I would like to know if you could give me some insight as to what you would attribute my dog stopping on a walk. The circumstance is I am walking with a friend and her well behaved dog and several times now he has stopped dead in his tracks after about 15-20 minutes of walking and will not budge  - he won't go forward at all just stands there planted. He is 2.5 yrs old and the dogs he walks with are well mannered and not paying him a lot of attention and at this point he has started doing his own thing checking out the smells and so forth but all the sudden he just will not budge. He has had hip, knee and front end x-rays and he is clear in  that respect. I have hopes that you could offer a suggestion I have not thought of and have it apply to this situation. When we get home from the walk I have let him out in the yard and he will zip around playful. Also, the dogs he walks with are dogs he knows well and has played with before.

Thank you in advance for your advice.

Answer
Hi Ann;
He could be tired, and suffering from Arthritis, as an X ray won't show that!
Or, he could just be in a mode, where you need some refresher training!
You can put him on a great product: www.BESTBREED.COM "Pernaflex"...for sure it won't hurt, and it may really do the difference!
A lot of older dogs get ligaments that stiffen and start to hurt, so, after the amount of time you mentioned, could really be the problem!

If not, you can take him to a class again, and try a "park environment" where he goes in a group for reinforcement training.
Best regards,
Melissa