23° 



ATLAS AND TEXT-BOOK OF HUMAN ANATOMY. 



to the external malleolus, as sometimes occurs, the ligament presents a cruciform appearance. 

 The outer undivided half of the ligament is connected at its origin with the inferior peroneal 

 retinaculum and the ligament contains three compartments separated by fibrous partitions, for 

 the three synovial sheaths. 



At the outer side of the ankle-joint the two peroneal muscles (longus and brevis) have a 

 common synovial sheath (Fig. 315), the upper and lower portions of which are usually sub- 

 divided for a short distance. This sheath is held in place by two retinacula which are frequently 

 indistinctly separated. The superior peroneal retinaculum (Figs. 307 and 315) passes from 



Tendon -sheath of tibialis anterior ~- 



Tendon-sheath of extensor hallncis longus 



Tendon-sheath of 

 tibialis posterior 



Tendon-sheath of 

 flexor digitorum 



Tendon-sheath of 

 extensor hallucis 

 longus 

 {&■'' Calcaneal tendon 



^ Laciniate Jig 



Tendon of flexor hallucis 

 long. 



Tendon-sheath 

 of flexor digi- 

 torum long. 



Tendon-sheath 

 of tibialis 

 posterior 



1 Abductor hallucis X 



Flexor digit, brevis X 



Fig. 316. — The tendon-sheaths and retinacula of the internal border of the foot (somewhat diagrammatic). 



the posterior border of the internal malleolus to the upper extremity of the tuberosity of the 

 calcaneus, and is also connected with the deep fascia of the leg. The inferior peroneal retinacu- 

 lum (Figs. 307 and 315) extends from the outer extremity of the cruciate ligament to the outer 

 surface of the calcaneus and its trochlear process. 



At the inner side of the ankle-joint (Fig. 316) there are three synovial sheaths for the tibialis 

 posterior, the flexor digitorum longus, and the flexor hallucis longus. The sheath for the tibialis 

 posterior is the shortest and extends only to the inner border of the foot. The two remaining 

 sheaths are continued into the sole of the foot and extend as far as the decussation of the tendons. 



