Bruises are due to effusion of blood into the tissues, due to the rupture of blood vessels. In which pa of the body a lesser impact causes maximum bruise?

If the pa is vascular and loose, such as face, vulva, scrotum a slight degree of violence may cause a large bruise because there is sufficient space for blood to accumulate. If the tissues are strongly suppoed, and contain firm fibrous tissues and covered by thick dermis, such as abdomen, back, scalp, palms and soles, a blow of moderate violence may produce a comparatively small bruise. Ref: The Essentials of Forensic Medicine and Toxicology by Narayan Reddy, 27th edition, Page 160-161.