Horse has hind end problems - Horse Chiropractor Mass.

Doing Butt Tucks is a great way to test your horse for engagement and tucking under the hind end to move forward. If your horse does not respond to this they may have an issue in the pelvis that a chiropractor can help.

Butt tuck can also be used to strengthen the abdominal muscles which will greatly help with rounding up the back.

Chiropractor for horse Mass. = Shod vs Barefoot Horse

http://www.youtube.com/watch?v=1-us0SxGL2o&feature=player_embedded

The above link is a great comparison. Note that normal gait pattern on hoof movement is heal then toe movement and many of these shod horses strick toe first which alters concussive forces on the hoof and adds to strain on leg joints and spine.