Quadrants The abdominal wall is divided into 4 quadrants which are defined by 2 planes: 1. Transumbilical plane – horizontal plane through the umbilicus at the IVD between L3 – L4. 2. Median plane- vertical plane dividing the body into right and left halves.Abdominal Regions • The abdomen is divided into 9 regions so that organ location and pain can be described. • The regions are delineated by 4 planes: 1. Right and Left midclavicular planes 2. Subcostal plane (sometimes a transpyloric plane is used) 3. Transtubercular plane which passes through the L5 vertebral body.