Dwarf hamster urinary habits

Question
We have a very healthy and energetic female dwarf, which is about 6 months old.

We are stumped over her habit (since day one!) of urinating ONLY while running on her wheel, or when in her exercise ball!  Within minutes of running, the wheel/ball is gross...and we can't even let her run for 10 minutes in the ball because of this!  

There is NO sign of urine anywhere else in the cage...I've had several hamsters throughout my life...but never this!

Is this a sign of something else wrong...is there something we can do to "toilet train" her to a corner?!

Thanks for your help! ;-)

Answer
Dear Kirsten,
thank you for your question.
I don't think there is something wrong with your hamster, but it is definitely unusual. You could try to rub the wheel with sand (the kind used for chinchillas and degus for bathing) to make the sand smell of her urine and then put that sand into a corner toilet, but I'm not sure this works. Dwarf hamsters need a sand bath anyway and the often use it as a toilet (it's best to offer two baths).
Just to be on the safe side: let a vet check the hamster. As I said, I don't think there's anything wrong, but I have no medical training and maybe it's a sign of illness after all.
I can only recommend to stop using the hamster ball. A hamster relies on his sense of smell, touch and hearing to find his way around and in a hamster ball all those senses are numbed and the hamster is virtually blind. Apart from that, the hamster's legs can get caught in the ventilation openings and this can result in broken bones since especially dwarf hamsters are too small to really control the ball. A hamster play pen with cardboard tubes and boxes, old clothes, hidden food ect. is much more interesting and less frightening and dangerous for the hamster.
I hope I was of some help
Jennifer