1076 THE ORGANS OF DIGESTION. 



eleventh rib. A lower border may be described between the phrenic and basal 

 surfaces. 



The upper end of the spleen lies on the level of the tenth dorsal vertebra. 

 It approaches the vertebral column to within 2 or 3 cm., and often touches it. 

 It is covered behind by the ribs and the great Sacro-spinalis muscle. 



The lower end of the spleen extends more or less forward, but normally, even 

 in deep inspiration, does not extend beyond the costo-clavicular line, which con- 

 nects the left sterno-clavicular articulation to the anterior end of the eleventh 

 rib. Frequently it only reaches the axillary line. In regard to the relations of 

 the spleen to the thoracic cavity and lung three zones can be distinguished (Fig. 

 687) : (1) The upper part of the spleen is completely covered by the left lung ; 

 (2) the middle part corresponds to the costo-phrenic sinus ; (3) the lower part 

 extends over the lower pleural limit and projects down over the costal origin of 

 the diaphragm. Its relations to the pleura and pleural cavity explain why 

 wounds of the spleen can be accompanied by wounds of the lung and why abscess 

 of the spleen may open through the diaphragm into the left pleural cavity. 



It can also be seen how the limit of percussion is very narrow. The upper 

 part is covered by the lung and thick muscles of the back. The part not covered 

 by the lung applies itself to the left kidney and splenic flexure of colon whereby 

 the percussion note may be modified, especially if faecal masses be in the colon 

 or if the fundus of the stomach be filled with food. Abnormal enlargements of 

 the spleen may be diagnosed by palpation as well as by percussion. 



Relations. 



Externally and above: 



Peritoneum and left costal part of diaphragm ; 



Ninth, tenth, and eleventh ribs ; 



Costo-phrenic sinus ; 



Left lung and pleura ; 



(At birth) left lobe of liver; 



Great muscles of back. 



Internally : 



Posterior surface of fundus of stomach ; 

 Left kidney and capsule ; 

 Tail of pancreas ; 

 Sometimes vertebral column. 



Inferiorly : 



Tail of pancreas sometimes ; 



Splenic flexure of colon ; 



Lig. phreno-colicum ; saccus lienalis. 



Fixation of Spleen and Peritoneal Relations. The position of the spleen is 

 secured by peritoneal folds which connect it with the diaphragm and neighboring 

 organs. 



The lig. pJireno-lienale comes from the left crus of the diaphragm, and passes 

 in the direction of the long 'axis of the spleen to its point of insertion, which is 

 directly behind the inner border (margo intermedius). The ligament consists of 

 firm connective tissue strands, and deserves the name suspensory ligament of the 

 spleen (lig. suspensorium lienis). 



The lig. gastro-lienale or g astro-splenic omentum connects the hilus of the 

 spleen with the fundus of the stomach. It consists of an anterior layer formed of 

 peritoneum of the greater sac, and a posterior layer which helps form the anterior 

 wall of the lesser sac (Fig. 611). It only receives a strong consistency by the 

 presence of the vasa gastrica brevia, Avhich run in this fold from the hilus of the 

 spleen to the stomach. The insertion of the ligament into the fundus of the 

 stomach has no firm hold and can offer but little fixation to the spleen, but 



