THORACIC ARTICULATIONS 



403 



which presents a surface corresponding with the rough depression in the end 

 cf the rib. Further sti^ength is given to this articulation by the periosteum, 



Fig. 41. — Inferior View of the Costo-Vertebral Articulations. 



1. 1. etc. Inferior common vertebral ligament. 



2. 2. etc. Inter-fibro-cartilaginous disc. 



3. 3. etc. Inferior costo-transverse ligament. 



4. 4. etc. Inferior costo-vertebral ligament. 



which, in passing from the bone to the cartilage, forms a strong uniting 

 band. 



The chondro-sternal articulations occur between the inferior extremity 

 of the cartilage of each rib, and the oblong cavities existing along each side 

 of the sternum. The eight anterior cartilages forai, with the fossae in the 

 sternum, eight corresponding articulations. 



The joints which result from the union of these two surfaces are 



Fig. 42.— Profile View of Sterno-Costal and Chondro-Costal Articulations. 



1. 1. Anterior end of sternum and cariniform car- 



tilage. 



2. Ensiform cartilage. 



3. 3. etc. Sternal cartilages. 



4. etc. Chondro-stenial articulati' ns. 



5. etc. Ends of the true ribs with the articula- 



tions between them, and the cartilages 

 seen between 3 and 5. 



enveloped on all sides by fasciculi of white and extended fibres, the whole of 

 which constitute a ligamentous capsule. The superior fibres are sometimes 

 described as the superior chondro-sternal ligament. The inferior are continu- 

 ous with the origin of the pectoral muscles. 



The foremost chondro-sternal articulation is not separated from the corre- 

 sponding one on the opposite side. The two cartilages being close together, 



