[yorkietalkjilly]

Here are some thoughts for what they are worth. You might need to train him to come up and down over and over and over, leading him with a juicy treat up and down, little at a time until he gets it and fees secure. Some dogs have a fear of heights. He could have fallen off a high place before you got him if he's a young dog or fallen when you weren't home. Or he's unsure of his leg strength or it hurts to jump that far. Outside, a dog will often do things that hurt some as they are excited and adrenaline pumping from all the excitement, scents and freedom. Inside, dogs can become more circumspect about doing something that basically hurts them. Canines are genetically programmed not to show pain when they can help it - they just endure it and start to avoid what hurts when not otherwise caught up in a frenzy of fun.

I was teaching Tibbe to bow on command and he became reluctant to go up his doggie stairs or ramp within a week of starting that training. I realized that bowing action could have stressed his shoulders or elbows and we stopped that trick then and there and I put away the stairs/ramps. I lifted him for the next two weeks up and down every time and then slowly allowed him to resume them and he did just fine going up and down but we never resume the bowing trick and never will. I would sure have my vet check him out for sore joints, occult injury and degenerative changes in joints or things like that on x-ray just to be sure. Jumping is way different from running and bounding outside, all of which Tibbe did when he was sore - but he was reluctant to use his stairs or jump as much as it takes to get down from or up on furniture in the house.