THE INTERCOSTAL NERVES 



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The Rectus Abdominis is a strap-like muscle, which arises 

 from the front of the pubis and extends upwards to the xiphoid 

 process and the adjoining costal cartilages. When it contracts, 

 it helps to flex the vertebral column, but, like the lateral 



\_Photo by AUnari. 



FTG. 69. The Nerve-supply of the Anterior Aspect of the Trunk. 



muscles of the abdominal wall, its main action is to assist 

 expiration by compressing the abdominal viscera so that the 

 liver may elevate the relaxed diaphragm. Further, in common 

 with the lateral muscles, the rectus normally influences the 

 muscular tonus of the alimentary canal, and improvement of 

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