PELVIC LIMBS. 
medial condyles (a and 4) of the tibia. The 
condyles are oval, convex dorsoventrad, and 
concave from side to side. The two con- 
dyles are separated at the middle of their 
contiguous margins by a bicuspid projection, 
the spine of the tibia (c). They are con- 
tinuous dorsad, but separated ventrad by a 
deep notch between the tuberosities, the 
popliteal notch. On the distal side of the 
lateral condyle is an elongated tacet for the 
proximal end of the fibula. 
The shaft is triangular, smallest at about 
its middle and enlarged at both ends. It 
presents dorsal, medial, and lateral borders, 
and medial, lateral, and ventral surfaces. 
The lateral surface is concave proximad. 
The medial surface is convex. The two 
are continuous at the distal end. At their 
proximal ends the border separating them 
is raised into a prominent ridge, the crest 
(@) of the tibia, the proximal end of which 
contributes to increase the proximal sur- 
face of the bone, and presents an oblong 
tubercle (¢) for the insertion of the liga- 
mentum patelle (ligament of the quadri- 
ceps femoris muscle). The ventral surface 
is concave proximad where it abuts upon the 
tuberosities. Its proximal half is crossed by 
two rough parallel lines, the distal one of 
which crosses in a spiral course from the 
lateral to the medial border; near its begin- 
ning is a nutrient foramen. 
The distal end extends farther distad on 
its medial side. The extension is the medial 
malleolus (7). The malleolus presents two 
grooves on its medial surface for the tendons 
of muscles. On the lateral side of the distal 
81 
Fic. 57.—TIBIA AND 
Fisuta oF Lerr 
Lec, DorsaL View. 
Z, tibia; 7, fibula. 
a, medial condyle of 
the tibia; 4, lateral con- 
dyle; ¢, spine of the 
tibia; @, crest of the 
tibia; ¢, tubercle for at- 
tachment of the patellar 
ligament; /, medial 
malleolus; g, projection 
of dorsal surface of the 
tibia; 2, head of fibula; 
z, lateral malleolus. 
end is an oblique triangular facet for the distal end of the 
