Might sitting on edge of seat w bladder prolapse cause blood clot?

Body: 

My mom (78) sits at the edge of the cushiony dining chair and she said she feels better. The wooden captains chairs make her back slouch....Her feet are better planted flat on the floor when she sits this way otherwise her feet dangle. She is 4 ft 6. We might cut the legs of the chair. Using blocks is a hazard. Does this pinch the leg arteries and can potentially cause thrombosis or a blood clot?

Forum:

Does your mom have circulatory problems? This question might be better answered by someone who knows all her medical issues. In my opinion, if she was sitting in such a way as to pinch off the leg arteries, she would probably become very uncomfortable long before she would do any damage. But I'm not a medical person.... - Surviving