a series of plane’s used as landmarks in thoracoabdominal topography; the trunk is divided vertically by a median plane from the upper border of the manubrium of the sternum to the pubic symphysis, by a lateral plane drawn vertically on either side through a point half way between the anterior superior iliac spine and the median plane at the interspinal plane, and by an interspinal plane passing vertically through the anterior superior iliac spine on either side; transversely the trunk is divided by a transthoracic plane passing across the thorax 3.2 cm above the lower border of the body of the sternum, by a transpyloric plane midway between the jugular notch of the sternum and the pubic symphysis, corresponding to the disc between the first and second lumbar vertebrae, and by an intertubercular plane passing through the iliac tubercles and cutting usually the fifth lumbar vertebra; the plane’s formed on these lines, and also on transverse plane’s cutting the upper edge of the manubrium and the upper edge of the pubic symphysis, constitute the clinical plane’s of Addison.