196 THE ARTICULATIONS OF THE LOWER LIMB. 



internal cuneiform ; the second is wedged in between the first and third cuneiform, 

 and rests against the second ; the third metatarsal bone articulates with the 

 extremity of the external cuneiform ; and the last two with the cuboid bone, the 

 fourth having also usually an articulation with the external cuneiform. The articu- 

 lations are synovial joints, and the bones are held in contact by dorsal, plantar, and 

 interosseous ligaments. 



The dorsal tarso-metatarsal ligaments (fig. 222) are flat thin bands of parallel 

 fibres, which pass from behind forwards, connecting the contiguous extremities of 

 the bones before mentioned. Thus the first metatarsal bone receives a broad thin 

 band from the corresponding cuneiform bone ; the second receives three, which 

 converge to its upper surface, one passing from each cuneiform bone ; the third has 

 one from the external cuneiform bone ; and, finally, the last two are bound by a 

 fasciculus to each from the cuboid bone, and by fibres from the external cuneiform 

 to the fourth metatarsal bone. The plantar ligaments are less regular ; the bands 

 of the first and second metatarsal bones are more strongly marked than the corre- 

 sponding ligaments on the dorsal surface ; and those of the fourth and fifth, which 

 are merely a few scattered fibres passing from the cuboid, receive support from the 

 prolongation of the long plantar ligament, forming the sheath of the peroneus 

 longus tendon. Ligamentous bands stretch in an oblique direction from the 

 internal cuneiform to the second and third metatarsal bones ; and others, less 

 developed, run nearly transversely from the external cuneiform to the fifth 

 metatarsal. 



The interosseous ligaments run forwards between the bones, and from their 

 strength and deep position oppose great resistance to the knife in separating the 

 metatarsus from the tarsus, a. The internal and largest of these extends from the 

 outer side of the first cuneiform bone to the neighbouring side of the second 

 metatarsal, close to the articular surface. Z>. The middle, which is the 

 smallest, and is less constant than the others, passes from the external cunei- 

 form to the outer side of the second metatarsal bone. c. The external connects 

 the outer side of the external cuneiform to the same side of the third metatarsal 

 bone. 



Synovial cavities. There are three synovial cavities in this irregular series of 

 articulations, a. One is between the internal cuneiform and the first metatarsal 

 bone ; the joint formed between these two bones is altogether separate and out of 

 the range of the rest. &. A second synovial cavity is between the cuboid and the 

 fourth and fifth metatarsal bones, and sends a small process forwards between the 

 latter bones, c. The third or middle one is placed between the middle and external 

 cuneiform and the second and third metatarsal bones, and is prolonged between the 

 two last-named bones, as well as between the third and fourth metatarsal bones. 

 This cavity generally communicates between the internal and middle cuneiform 

 bones with that of the naviculo-cuneiform articulation. 



INTERMETATARSAL ARTICULATIONS. The metatarsal bones are bound together 

 at their tarsal and digital ends ; very firmly in the former, and loosely in the latter 

 situation. 



The tarsal ends of the four outer bones articulate with each other, having lateral 

 cartilaginous surfaces, between which processes are sent forwards from the outer two 

 synovial cavities of the tarso-metatarsal articulations, and they are connected by 

 dorsal, plantar, and interosseous ligaments. The dorsal and plantar ligaments are 

 short transverse bands stretching across the four metatarsal bones from one to 

 another. The interosseous ligaments, lying deeply between the bones, connect the 

 rough parts of their lateral surfaces ; they are of considerable strength and firmness. 

 Between the first and second metatarsal bones there is often a bursa, corresponding 

 to a small articular facet on the base of the former bone, while on the latter there is 



