306 



THE ARTICULATIONS 



The talo -navicular ligament is a broad, thin, but well-marked layer of fibres which passes 

 from the dorsal and lateral surfaces of the neck of the talus to the whole length of the dorsal 

 surface of the navicular. Many of the fibres converge to theii- insertion on the navicular. The 

 fibres low down on the lateral side blend a Httle way from their origin with the upper edge of 

 the lateral calcaneo-navicular ligament, and then pass forward and medially to the navicular; 

 those next above pass obhquely and with a distinct twist over the upper and lateral side of the 

 head of the talus to the centre of the dorsum of the navicular, overlapping fibres from the medial 

 side of the talus as weU as some from the anterior ligament of the ankle-joint. 



Synovial membrane. — The talo-navicular is Uned by the same synovial membrane as the 

 anterior talo-calcaneal joint. 



(ii) The Calcaneo-cuboid Articulation 



Class. — Diarthrosis. Subdivision. — Saddle-shaped Arthrodia. 



The ligaments which are supplementary to the articular capsule and unite 

 the bones forming the outer part of the medio-tarsal joint are: — 



Medial calcaneo-cuboid. 

 Long plantar. 



Dorsal calcaneo-cuboid. 

 Plantar calcaneo-cuboid. 



The medial calcaneo-cuboid ligament (fig. 335) is a strong band of fibres attached to the 

 calcaneus along the medial part of the non-articular ridge above the articular facet for the cuboid, 

 and also to the upper part of the medial surface close to the articular margin, and passes forward 

 to be attached to the depression on the medial surface of the cuboid, and also to the rough angle 



Fig. 336. — Ligaments of the Sole of the Left Foot. 



Long plantar ligament 



Tendon of peroneuslongus 



Groove for flexor hallucis longus 



Plantar calcaneo-navicular ligament 



W Plantar calcaneo-cuboid 



(short plantar) ligament 



Tubercle of navicular 



Medial cuneiform 



Insertion of peroneus longus 



between the mcflial and inferior surfaces. At the calcaneus this ligament is closely connected 

 with the latoral calcarico-navifular ligament. Toward the sole it is connected with the plantar 

 calcaneo-cuboid ligarnont, and superiorly with the dorsal calcaneo-cuboid. 



1'he dorsal calcaneo-cuboid (fig. 335) is attached to the dorsal surfaces of the two bones, 

 extending low down laterally to blend with the lateral part of the plantar calcaneo-cuboid 

 ligament. Over the medial half, or more, the ligament stretches some distance beyond the mar- 

 gins of the articular surfaces, reaching well forward upon the cuboid to be attached about 

 midway between its anterior and posterior borders; biit toward the lateral side, the ligament 

 is much shorter, and is attached to the cuboid behiiul its tubercle. 



