TARSO-METATARSAL. 233 



6. TAKSO-METATARSAL ARTICULATIONS. 



These are arthrodial joints. The bones entering into their formation are the 

 internal, middle, external cuneiform, and cuboid, which articulate with the meta- 

 tarsal bones of the five toes. The metatarsal bone of the great toe articulates with 

 the internal cuneiform ; that of the second is deeply wedged in between the in- 

 ternal and external cuneiform, resting against the middle cuneiform, and being the 

 most strongly articulated of all the metatarsal bones ; the third metatarsal articu- 

 lates with the extremity of the external cuneiform ; the fourth with the cuboid 

 and external cuneiform ; and the fifth with the cuboid. The articular surfaces 

 are covered with cartilage, lined by synovial membrane, and connected together 

 by the following ligaments : 



Dorsal. Plantar. 



Interosseous. 



The Dorsal Ligaments consist of strong, flat, fibrous bands, which connect the 

 tarsal with the metatarsal bones. The first metatarsal is connected to the internal 

 cuneiform by a single broad, thin, fibrous band; the second has three dorsal 

 ligaments, one from each cuneiform bone ; the third has one from the external 

 cuneiform ; and the fourth and fifth have one each from the cuboid. 



The Plantar Ligaments consist of longitudinal and oblique fibrous bands con- 

 necting the tarsal and metatarsal bones, but disposed with less regularity than on 

 the dorsal surface. Those for the first and second metatarsal are the most strongly 

 marked ; the second and third receive strong fibrous bands, which pass obliquely 

 across from the internal cuneiform ; the plantar ligaments of the fourth and fifth 

 consist of a few scanty fibres derived from the cuboid. 



The Interosseous Ligaments are three in number : internal, middle, and external. 

 The internal one passes from the outer extremity of the internal cuneiform, to the 

 adjacent angle of the second metatarsal. The middle, one, less strong than the 

 preceding, connects the external cuneiform with the adjacent angle of the second 

 metatarsal. The external interosseous ligament connects the outer angle of the 

 external cuneiform with the adjacent side of the third metatarsal. 



The Synovial Membranes of these articulations are three in number : one for 

 the metatarsal bone of the great toe, with the internal cuneiform ; one for the second 

 and third metatarsal bones, with the middle and external cuneiform, which is 

 continuous with the great tarsal synovial membrane ; and one for the fourth and 

 fifth metatarsal bones with the cuboid. The synovial membranes of the tarsus 

 and metatarsus are thus seen to be six in number (fig. 146). 



/ 

 ARTICULATIONS OF THE METATARSAL BONES WITH EACH OTHER. 



The bases of the metatarsal bones, except the first, are connected together by 

 dorsal, plantar, and interosseeus ligaments. The dorsal and plantar ligaments 

 pass from one metatarsal bone to another. The interosseous ligaments lie deeply 

 between the rough non-articular portions of their lateral surfaces. The articular 

 surfaces are covered with cartilage, and provided with synovial membrane, con- 

 tinued forwards from the tarso-metatarsal joints. The digital extremities of the 

 metatarsal bones are united by the transverse metatarsal ligament. It connects 

 the great toe with the rest of the metatarsal bones ; in this respect it differs from 

 the transverse ligament in the hand. 



Actions. The movement permitted in the tarsal ends of the metatarsal bones is 

 limited to a slight gliding of the articular surfaces upon one another ; considerable 

 motion, however, takes place in their digital extremities. 



METATARSO-PHALANGEAL ARTICULATIONS. 



The heads of the metatarsal bones are connected with the concave articular 

 surfaces of the first phalanges by the following ligaments : 



Anterior or Plantar. Two Lateral. 



