VEINS. 



473 



It extends in, in the crest of the neck of the rib to the lower border of the 

 transverse process of the v<Ttebr;i next above. 

 Hare all tlic costal heads capsules / 



No ; the eleventh and twelfth have none, their union being fibrous. 

 The anterior part of the thorax has the following articulations : 



1. IntersternaL, binding sternal ligaments together. 



2. Costo-eliondral, binding the ribs to their cartilages. 



3. Chondro-sternal, binding the costal cartilages to the sternum. 



4. Interchondral, binding the sixth, seventh, eighth, ninth, and tenth costal 

 cartilages together. 



The superior intcrstcrnal articulation is an ainpliiarthrodial joint. 



The manubrium and gladiolus are bound together by an anterior and a poste- 

 rior common sternal ligament and by an interosseus fibro-cartilage. This ridge or 

 junction may be considered valuable in physical diagnosis as a guide to counting 

 the ribs, since it corresponds to the cartilage of the second rib. 



The inferior intcrstcnial articulation is between the gladiolus and cnsiforin parts 

 of the stern n in. 



By this union these two pieces form a synarthrodial joint. 



THE CHONDRO-STERNAL ARTICULATION. 



WJierein docs the articulation of the first rib differ from the others in its articu- 

 lation -i^'ith the sternum .' 



It is synarthrodial ; the others are diarthrodial, the hinge or ginglymoid 

 variety. 



Name the ligaments of the chondro-sternal joints. 



1. Anterior chondro-sternal. 



2. Posterior chondro-sternal. 



3. Superior chondro-sternal. 



4. Inferior chondro-sternal. 



Explain the nerve-supply of the intrinsic thoracic joints. 



(i) The costocentral is supplied by the intercostal nerves ; (2) the costotrans- 

 verse is supplied by intercostal nerves ; (3) the chondro-sternal is supplied by the 

 intercostals. 



SOME INTERESTING FACTS ABOUT VEINS. 



Veins have more extensive anastomoses than arteries. 

 Veins carry blood toward the heart ; arteries from the heart. 

 Pulmonary veins return aerated blood from the lungs. 

 Systemic veins return CO 2 laden blood from the body general. 

 Veins are arbitrarily classed as superficial and deep. 

 Systemic veins terminate in the superior and inferior vena: cav;u. 

 Superficial veins are located in the superficial fascia. 

 Superficial veins communicate with deep veins through deep fascia. 

 Deep-veins accompany arteries in one and the same sheath. 

 The portal vein takes blood from abdominal digestive organs to liver. 

 Visceral veins usually take the name of the organ they drain. 

 Deep veins below the elbow and knee are called vena: comites. 

 The larger arteries are attended by one vein only. 

 Veins collapse when empty ; arteries remain open. 

 Superficial veins have thicker walls than deep veins. 

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