My one does the same thing but i think she just turns into another dog when she is out side.
My boyfriend has two kids and i swear she runs back and forth and if i hold her back she yelps like i'm hurting her! its so embarrassing because she moves around like crazy and once i put her down she does the same thing she pulls to where she is on her back to legs. Then she pulls so hard that last week her back paw ripped and i had to take her to the ER because the bleeding. So i'm planning on seeing a trainer friday and if i have anything good i'll post it up! But if anyone has advice please let me know!!! I need it!!!