Jane, my father fell out of bed at a SNF. The staff changed his standard alternating pressure mattress to one with higher sides. They weren't much higher than the flat mattress, perhaps 4" - 5" or so, but the theory was that he would have to roll and move upward before falling out. So, the more or less "ridge" blocked rolling out.
He didn't fall out again, but I don't know if it was b/c of the rolled sides or b/c the same situation just didn't occur again.
Your profile says mom is in nursing home. Or is she in your home? Bedrails are considered restraint and too often the ill get tangled up in them trying to climb over them. Not considered safe.
Jane, I believe many of the posters on this site have had loved ones who fell --- more than once. Bed rails are illegal in most states. Can you tell us more about Mom's living arrangements? Is she in her own home? Your home? A facility? Does hospice send an aide for 2 hours a day? Was anyone else in the house at the time? etc etc. I know it is difficult to see our family hurt. But it is also impossible to watch them every moment.
He didn't fall out again, but I don't know if it was b/c of the rolled sides or b/c the same situation just didn't occur again.