LIGAMENTS OF TARSAL BONES. 



227 



ligaments. 



triangular facet internally for the internal calcaneo-navicular liga- 

 ment. The surface of the navicular bone is hollowed, and is 

 widest externally. 



Movement. The navicular moves down and in over the head of Movement : 

 the astragalus in inversion, or up and out in eversion. 



As the bone is forced downwards, the upper and external liga- state of 

 inents of the joint are made tight ; 

 and when the navicular is moved in 

 the opposite way, the strong internal 

 ligament is put on the stretch. 



THE os CALCIS WITH THE CUBOID 

 BOXE. The ligaments in this articu- 

 lation are plantar, dorsal, and 

 internal . 



The dorsal, or superior, calcaneo- 



lmitl ligament (fig. 87, #) is a rather 

 thin fasciculus of fibres, which is 

 attached near to the contiguous ends 

 of the os calcis and the cuboid bone ; 

 it is sometimes divided into two 

 pieces, or it may be situate at the 

 outer border of the foot. 



At the inner side of the cuboid 

 bone is a variable internal band 

 (fig. 87, /) from the os calcis ; this 

 is fixed behind to the upper part of 

 the os calcis, outside the band to 

 the navicular bone, and in front to 

 the contiguous inner side of the 

 cuboid. 



The itifi-rinr cul'-iineo-cuboid liga- 

 ment is much the strongest, and is 

 divided into superficial and deep 

 parts : 



The superficial portion or loiuj 

 plantar liyarnent (fig. 88, ! ) is attached 

 to the under-surface of the os calcis 

 between the posterior and the anterior 

 tubercles ; its fibres pass forwards to 

 be connected with the ridge on the 

 under-surface of the cuboid bone ; 

 but the most internal are continued 



over the tendon of the peroneus longus muscle, assisting to form its 

 sheath, and are inserted into the bases of the third and fourth 

 metatarsal bom-<. 



The deep piece or short plantar ligament (fig. 89, b), seen on deep band 

 division of the superficial (a), extends from the tubercle and the 

 hollow on the fore part of the under-surface of the os calcis to the 

 cuboid bone internal or posterior to the ridge. 



The synovial cavity of the articulation is simple. 



Q 2 



internal, 



FIG. 89. VIEW OF THE INFERIOR 

 LIGAMENTS OF THE TARSAL 

 1 JUNES. 



a. Long plantar cut. 



b. Short or deep inferior cal- and inferior 

 caneo-cuboid ligament. ligaments. 



c. Internal calcaneo-navicular. 



d. Plantar transverse navi- 

 culo-cuboid ligament. 



e. Dorsal inner naviculo- 

 cuneiform extending into the JJ^Xst 8 

 sole of the foot. and d f vid ' ed 



/. Plantar transverse ligament into two 

 between the inner and middle P ar ts : 

 cuneiform bones. 



g. Plantar transverse band 

 between the cuboid and outer 

 cuneiform. 



superficial 

 and 



Synovial 

 sac. 



