274 LIGAMENTS OF THE FOOT. 



its upper part for the passage of the obturator vessels and nerve. 

 It assists in supporting the contents of the pelvis, and in giving 

 origin to the obturator muscles. See fig. 62, p. 257. 



The interosseous ligament of the leg fills the space between 

 the tibia and fibula like the interosseous ligament of the forearm, 

 and is of a similar structure ; being formed of the oblique fibres, 

 and perforated in various places for the passage of vessels and 

 nerves. 



At the upper part of it there is a large opening, where the 

 muscles of the opposite sides are in contact ; and where vessels 

 and nerves pass to the fore part of the leg. 



It serves chiefly for the origin of part of the muscles which 

 belong to the foot. 



Ligaments retaining the Tendons of the Muscles of the Foot 

 and Toes in their proper position. 



The annular ligament of the tarsus is a thickened part of 

 the aponeurosis of the leg, splitting into superior and inferior 

 portions, which bind down the tendons of the extensors of the 

 toes upon the forepart of the ankle. 



The vaginal ligament of the tendons of the peronei muscles, 

 behind the inkle is common to both, but divides at the outer 

 part of the foot, and becomes proper to each. They preserve* 

 the tendons in their places, and are (he bursas of these tendons. 



The laciniated ligament arises from the inner ankle, and 

 spreads in a radiated manner, to be fixed partly in the cellular 

 substance and fat, and partly to the os calcis, at the inner side 

 of the heel. It encloses the tibialis posticus and flexor digitorum 

 longus. 



The vaginal ligament of the tendon of the extensor proprius 

 pollicis runs in a crucial direction. 



The vaginal ligament of the tendon of the Jlcxor longus 

 pollicis surrounds this tendon in the hollow of the os calcis. 



The vaginal and crucial ligaments of the tendons of the flexors 

 of the toes inclose these tendons on the surfaces of the pha- 

 langes, and form their bursa mucosae. 



The accessory ligaments of the flexor tendons of the toes, as in 



