Crooked body conformation, needs help in rear!

[brumby@verizon.net]

I now own a 21 year old mare who was a rescued horse. She has since put on over 250 pounds and is doing much better. She has a very crooked front leg (probably from birth). I believe she has compensated for years in the rear--on the same side (right side) she has an almost fused stifle with arthritis in that leg. With the lameness on the same side it is awkward at the least. When she walks she often limps until she loosens up. In the rear both of her feet twist shearing off the outside hoof walls. I've had 3 different farriers check her out and the consensus was if it causes too much pain to put on shoes in the rear (the vet originally wanted reverse shoes to support the stifle injury) that it is a better choice to leave her without shoes in the rear even though she really needs the support. It seems to hurt her to hold herself up in the rear, either its the stifle or sore hips, or psychological, who knows. Is there any treatment available at all that can be applied with really limited lift in the rear? She limps terribly on the gravel on the driveway as well. (much better once we get to the grassy fields) She is on Adequan and hoof supplements. We have tried many times to get MSM and joint supplements that she'll accept, but no matter how we doctor it, she refuses them. Please email any responses to brumby@verizon.net thanks very very much!