JOINTS OF THE FOOT 433 



the long plantar ligament and the plantar calcaneo-cuboid 

 ligament have an importance which is surpassed only by that 

 of the plantar calcaneo-navicular ligament. 



The joint between the talus and the navicular and that between the 

 calcaneus and the cuboid are frequently referred to together as the trans- 

 verse tarsal joint. It is there that some parts of the movements of eversion 

 and inversion of the foot take place. It should be noted that all the 

 ligaments which connect together the anterior and the posterior segments 

 of the tarsus at this joint, except one, are attached posteriorly to the 

 calcaneus. They are : 



Plantar calcaneo-navicular, 



Bifurcate, 



Long plantar, 



Plantar calcaneo-cuboid, 



Calcaneo-cuboid capsule, 



Dorsal talo-navicular, 



Attached to the calcaneus. 



Attached to the talus. 



Inter - cuneiform Articulations. The three cuneiform 

 bones are held together so firmly that very little individual 

 movement is permitted. The chief uniting structures are 

 two strong interosseous ligaments which pass between the non- 

 articular portions of their opposed surfaces. These can be 

 seen only when the bones are separated from each other. 

 Dorsal inter-cuneiform ligaments also are present. These are 

 short, flat, transversely-placed bands. 



Cuneo - navicular Articulation. - - The three cuneiform 

 bones articulate with the anterior surface of the navicular. 

 They are held in position by dorsal ligaments, which pass from 

 the dorsal surface of the navicular to the dorsal surface of each 

 of the cuneiform bones, and by plantar ligaments, which are 

 similarly disposed. The strength of the plantar ligaments is 

 greater than that of the dorsal ligaments, and they are 

 reinforced very largely by slips from the tendon of the tibialis 

 posterior. 



Dissection. The dissector may now divide freely all the 

 dorsal and the most medial of the plantar cuneo-navicular liga- 

 ments. The navicular bone can then be drawn backwards so 

 as to expose the interior of the joint. The knife may also be 

 carried round the lateral side of the lateral calcaneo-navicular 

 ligament. A much better view of this ligament is thus obtained, 

 although this dissection entails the division of the dorsal cubo- 

 navicular ligament. 



The convex anterior articular surface of the navicular fits 

 into a transversely concave socket, which is formed for it by 

 the posterior surfaces of the three cuneiform bones, "and, often, 



VOL, i 28 



