OF THE RIBS WITH TRANSVERSE PROCESSES. 277 



2. ARTICULATION OF THE NECK AXD TUBERCLE OF THE RIBS WITH THE 

 TRANSVERSE PROCESSES. (Fig. 192.) 



The ligaments connecting these parts are 



Anterior Costo-transverse. 



Middle Costo-transverse (Interosseous). 



Posterior Costo-transverse. 



Capsular. 



The Anterior Costo-transverse Ligament is a broad and strong band of fibres, 

 attached below to the sharp crest on the upper border of the neck of each rib, 

 and passing obliquely upwards and outwards, to the lower border of the trans- 

 verse process immediately above. It is broader below than above, broader and 



Fig. 192, Costo-transverse Articulation. Seen from above. 



tYNOVIAL CAVITY 



CAPSULAR MEMBRANC 



thinner between the lower ribs than between the upper, and more distinct in 

 front than behind. This ligament is in relation, in front, with the intercostal 

 vessels and nerves; behind, with the Longissimus Dorsi. Its internal border 

 completes an aperture formed between it and the articular processes, through 

 which pass the posterior branches oT the intercostal vessels and nerves. Its 

 external border is continuous with a thin aponeurosis, which covers the External 

 Intercostal muscle. 



The^rs^ and last ribs have no anterior costo-transverse ligament. 



The Middle Costo-transverse or Interosseous Ligament consists of short, but 

 strong, fibres, which pass between the rough surface on the posterior part of 

 the neck of each rib, and the anterior surface of the adjacent transverse process. 

 In order fully to expose this ligament, a horizontal section should be made 

 across the transverse process and corresponding part of the rib; or the rib may 

 be forcibly separated from the transverse process, and its fibres put on the 

 stretch. 



In the eleventh and ttvelfth ribs, this ligament is quite rudimentary. 



The Posterior Costo-transverse Lif/ament is a short, but thick and strong, 

 fasciculus, which passes obliquely from the summit of the transverse process 

 to the rough non-articular portion of the tubercle of the rib. This ligament 

 is shorter and more oblique in the upper than in the lower ribs. Those cor- 



