Dear thanks for the question. Rigidity in abdomen is an indication of serious illness. It indicates irritation of peritoneum or infections of peritoneum. This can happen due to perforation of some hollow organ like intestine, ureter, stomach, uterus or bladder. In your mother s case it could be bladder, ureter or kidney perforations. You need to get an ultrasound scan of abdomen to come to a diagnosis and it will help in treatment too. She needs to be admitted in a multi purpose hospital. A team work by doctors can manage her condition. I hope my reply will benefit you. Please write for follow up queries. I wish your mother good health and faster recovery. Kindly hit a thanks. Thank you