Our 10+ year old brown dutch rabbit Baxter had front legs that he placed to the side. In the picture below you can see his white feet are placed out from his body at about the shoulder while the other two younger rabbits have their front feet firmly under them.
It developed over about 12 to 18 months, subtle at first, as slight position change when resting, but they would be under him when running/hopping. At the end his legs where splayed out from his body, and nearly useless. Near the end he would sometimes step on a front foot with a back foot.
Baxter (now passed) was a rescue rabbit who spent 6+ years in class room. Symptom on set was around 8 years of age, he has a history of morbid obesity and poor alignment of his back teeth.
What is the name and cause of this?