From: Rabbi Moshe Sofer
To: Unknown recipient
The Chasam Sofer rules unequivocally that an animal with one hip higher than the other but no limp is simply the blemish called kasul and has no treifah implications, requiring no examination. He sharply distinguishes this from nishmeta yereicha (dislocated thigh), which carries treifah status only when the hip cartilage has dissolved. He dismisses the correspondent's lengthy pilpul as largely incorrect.
Source: Shu"t Chasam Sofer YD §56