136 



Bones of the Lower Extremity. 



Condylus 

 lateralis 



Apex 



Capi- 

 tulum 

 fibulae 



Margo 



infra- 



glenoidalis 



- Condylus 

 medialis 



Tuberositas 

 tibiae 



Fades 

 lateralis" 



Facies 

 medialis 



Crista 

 anterior 



Crista 

 interossea 



Crista 

 medialis 



Crista 

 lateralis 



Fibula - >- 



Facies medialis 



Crista anterior 

 Facies lateralis 



Crista interossea 

 Margo medialis 



Tibia 



jMalleolus 1 



lateralis 



Malleolus 

 medialis 



ISO. Right shin bone 

 and calf bone, 



tibia and fibula, from in front. 



The tibia (shin bone) (see also Figs. 180 a . 

 181 185) is a long, strong cylindrical bone 

 and lies in the medial portion of the leg; it 

 articulates above with the femur, below with 

 the tarsus and also, above and below, with 

 the fibula. It is divisible into a shaft or 

 corpus and two extremities. 



The corpus tibiae (shaft) (see also 

 Figs. 180 a , 181, 184 and 185) is triangularly 

 prismatic in its upper two-thirds, quadrilateral 

 below, possesses a posterior, nearly flat surface, 

 fades posterior, a smooth, somewhat convex 

 surface looking forward 'and median ward, fades 

 medialis, and a slightly concave surface directed 

 forward and lateralward, fades lateralis. Of 

 the three borders where the surfaces meet, the 

 anterior, crista anterior, is the sharpest ; the 

 laterally directed crista interossea is less 

 sharp, while the medial, margo medialis, is 

 rounded off. At the uppermost part of the 

 posterior surface a rough ridge, linea poplitea 

 (popliteal line), extends obliquely from above 

 and lateralward, downward and medial ward. 

 At the junction of the upper and middle thirds 

 there is behind usually a large foramen 

 nutridum which leads into a distally directed 

 canalis nutricius. 



The upper extremity of the tibia (see 

 also Figs. 181, 182, 184 and 185) is broadened 

 markedly to form on the two sides the tibial 

 condyles, condylus medialis (0. T. internal 

 tuberosity) and condylus lateralis (0. T. ex- 

 ternal tuberosity). Each of these possesses a 

 proximally directed, triangularly oval, somewhat 

 depressed fades articularis superior, covered 

 with cartilage; between the two lies a rough 

 surface, broader in front and behind, which is 

 elevated in the middle to form the eminentia 

 inter condyloidea (0. T. spinous process) where 

 it ends in two small spurs, the tuberculum 

 intercondyloideum mediale and the tuberculum 

 intercondyloideum lalerale. The area in front 

 of the eminence is called the fossa inter- 

 cortdyloidea anterior t that behind it the fossa 

 inter condyloidea posterior. The surface covered 

 with cartilage is continued on each side for a 

 certain distance upon the eminence. On the 

 outer circumference of the facies articularis 

 superior the bone falls suddenly as the margo 

 infraglenoidalis. Below this, at the upper 

 end of the crista anterior, a rough broad, 

 projecting spur is visible, the tuberositas 

 tibiae (0. T. tubercle); at about the same 

 level on the posterior lateral part of the con- 

 dylus lateralis lies a small, flat, oval articular 

 surface for the capitulum fibulae, fades arti- 

 cularis fibularis. 



