216 HANDBOOK OF ANATOMY 



As a rule the tip of the twelfth rib lies 2 inches vertically 

 above the centre of the iliac crest. 



The " triangle of Petit" is a narrow triangular space formed 

 by the outer border of latissimus dorsi, the posterior border 

 of obliquus externus, and the iliac crest. 



The Kidneys. The upper limit of the kidney is indicated by 

 a line drawn transversely at the level of the eleventh dorsal 

 spine, the lower limit by one at the level of the third lumbar 

 spine. About a third of the kidney lies above the lower margin 

 of the twelfth rib, the left kidney about J inch higher than 

 the right. The most external point of the outer border lies 

 4 inches from the mid-line and the hilum lies H inches from 

 the mid-line between the tips of the transverse processes of the 

 first and second lumbar vertebrae. 



The Diaphragm and Liver. Posteriorly the right arch of 

 the diaphragm and the right lobe of the liver extend upwards to 

 the level of the angle of the scapula (eighth rib), while the left 

 arch lies 1 inch lower; the central tendon is on a level with 

 the eighth dorsal spine. The right lobe of the liver is covered 

 posteriorly by the eighth to the twelfth ribs. 



The Spleen is situated in the left hypochondrium behind the 

 cardiac end of the stomach, and is overlapped by the ninth, 

 tenth, and eleventh ribs, the long axis corresponding to that of 

 the tenth rib. 



The anterior angle is at the level of the ninth interspace in the 

 mid-axillary line. The vertebral angle lies 1J inches external to 

 the tenth dorsal spine. The inferior angle lies opposite the 

 eleventh interspace on a level with the first lumbar spine : with 

 these points the whole organ can be mapped out. 



The Upper Extremity. 



The Shoulder. The shaft of the clavicle is subcutaneous 

 throughout. The tip of the acromion lies a little external to and 

 in front of the outer end of the clavicle; and its outer border 

 can be followed round along the spine of the scapula, the root 

 of which is on a level with the third dorsal vertebra. The 

 inferior angle and internal border of the scapula are easily felt. 

 The tip of the coracoid process can be felt at the anterior border 



