ARTICULATIONS BETWEEN BONES OF THE TARSUS 427 



faces, one anterior, the other posterior ; and also with the os cuneiforme 

 magnum by two simihir surfaces. The os scaphoides articulates with the 

 magnum by a vast convex surface ; the cuneiforme and magnum articulate 

 internally and laterally with the parvum. 



The ligaments which keep these diarthrodial surfaces in contact are 

 numerous. The astragalo-metatarsal and the posterior tarso-metatarsal 

 ligaments are common to this articulation. They consist of — 



Ttvo mderior ligaments, running from the cuboid to the os scaphoides 

 and magnum, one above and the other below the groove between these three 

 bones. 



Two interosseous ligaments from tlie superior and inferior sides of the 

 forenamed gi^oove. 



A7i interosseous ligament, running from the os scaphoides to the cunei- 

 forme parvum. 



An interosseous ligament I'unning from the os scaphoides to the cunei- 

 forme magnum. 



The synovial membrane is formed between the os scaphoides and . os 

 cuneiforme : this membrane belongs also to the two arthrodial surfaces 

 existing on the upper parts of the internal surface of the os cuboides and 

 OS cuneiforme parvum. A capsule proper also exists between the superior 

 surface of the astragalus, the superior surface of the os scaphoides, and os 

 cuboides. As to the arthrodial surfaces between the os cuneiforme medium 

 on the one side, and the os cuboides and cuneiforme parvum on the other, 

 they are supplied with synovial membranes by two prolongations from the 

 tarso metatarsal synovial caj)sule. 



Movements. — Scarcely any. 



Articulations between the two rows. — This arthrodia is formed by 

 the union of the inferior extremity of the astragalus and os calcis, on the 

 one part, with the superior extremity of the os scaphoides and os cuboides 

 on the other. This articulation has six principal ligaments. 



The two superficial lateral ligaments of the tibio-tarsal articulation. 



The calcaneo-metatarsal ligament, which unites the posterior border of 

 the OS calcis to the cuboid bone and to the head of the external small meta- 

 tarsal bone. 



The astragalo-metatarsal ligament is a large radiating fasciculus, whose 

 fibres run from the tuberosity of the astragalus, diverge, and become con- 

 founded with the internal superficial tarsal ligaments on the ossa cunei- 

 forme magnum, scaphoides, and the superior extremity of the large meta- 

 tarsal bone. 



The posterior tarso-metatarsal ligament is very strong, and unites, poste- 

 riorly, the tarsal bones to the three metatarsal bones ; it is continuous 

 below with the suspensory ligament; it mixes at the sides with the cal- 

 caneo-metatarsal ligament, and with the internal and supei'ficial tarsal 

 ligament. 



An interosseous ligament is attached to the four bones which form this 

 articulation. 



It is provided with a synovial capsule, which always communicates 

 in front with the tibio-tarsal capsule. This capsule prolongs itself supe- 

 riorly between the os calcis and astragalus, to lubricate the two inferior 

 arthrodial surfaces between these bones. It also descends between the 



