112 



BONES OF THE LOWER LIMB. 



separated from the internal by a smooth rounded border, and from the 

 external by a sharp ridge, inclined forwards above, to which the inter- 

 osseous membrane is attached. Near the popliteal line is a large me- 



Fig. 100.— Right Tibia from behind. (A. T.) i Fig. 100. 



6, and 9, as in the preceding figure ; 2', groove behind 6 



the internal tuberosity for the tendon of the semi-mem- .j^^^^-^ 



branosiis muscle ; 10, inclined articular facet below and 

 behind the outer tuberosity for the head of the film la ; 

 11, oblique line of tibia, above which is the triangular 

 pojiliteal surface ; 12, nutritious foramen directed 

 downwards ; 13, triangulai- rough surface for the lower 

 interosseous ligament, and small cartilaginous surface 

 below it for articulation with the fibula ; 14, below a 

 slight groove marking the place of the flexor longns 

 poUicis muscle ; 15, below the groove of the tendons of 

 the flexor communis digitorum and tibialis posticus 

 muscles. 



dullary foramen, directed downwards into 

 the interior of the bone. 



The inferior extremity, much smaller than 

 the superior, is expanded transversely, and 

 projects downwards on its inner side, so as 

 to form a thick process, the internal malteo- 

 liis. Inferiorly it presents for articulation 

 with the astragalus a cartilaginous surface, 

 which is quadrilateral, concave from before 

 backwards, and having its posterior border 

 narrower and projecting farther downwards 

 than the anterior ; internally the cartila- 

 ginous surface is continued down in a 

 vertical direction upon the internal malleo- 

 lus, clothing its outer surface somewhat 

 more deeply in front than behind. The 

 external surftice, slightly concave, is rough 

 superiorly for ligament, and smooth below 

 for articulation with the fibula. The pos- 

 terior surface of the internal malleolus is 

 marked by a double groove for the tendons 

 of the tibialis posticus and flexor longus 

 digitorum, and more externally by a slight 

 depression where the flexor longus pollicis 

 lies ; the inner surface of the malleolus is 

 subcutaneous. 



The tibia is slightly twisted, so that when 

 the interaal malleolus is directed inwards, 

 the internal tuberosity is inclined backwards. 



1|« 



-IS 



^13 n 



THE FIBULA. 



The fibula, or 'peroneal hone, is situated at the outer side of the leg : 

 it is nearly equal to the tibia in length, but is much more slender. Its 

 inferior extremity is placed a little in advance of the superior ; and 

 its shaft is slightly curved, so as to have the convexity directed back- 

 wards, and, in the lower half, slightly inwards towards the tibia. 



