150 ANATOMY IN A NUTSHELL. 



space above each condyle is the origin of one head of the Gastrocnemius. 

 The distal extremity has two condyles, which are united anteriorly but 

 separated posteriorly by the intercondylar notch. The external condyle 

 is broader and more prominenl anteriorly, while the internal one is more 

 prominent internally, and it extends to a lower level, when the femur is taken 

 from the body. When the femur articulates with the tibia the two condyles 

 .,,,. (l|1 the -mum' level. Both condyles are convex for the articulation of the 

 tibia, and between these two anteriorly is a concave strface for the articula- 

 tion of the patella. The patellar surface has a vertical hollow and two lips. 

 The external portion which is wider and more prominent than the internal por- 

 tion rises higher. The tibial surfaces are almost parallel being a little closer 

 anteriorly than posteriorly. The lateral surface of each condyle extends into 

 :i tuberosity or epicondyle, which gives attachments to ligaments. Above the 

 external condyle is a depression for the outer head of the Gastrocnemius. The 

 inner head of the < hisirocnenhns arises from the upper part of the inner condyle. 

 The [ntercondyleae fossa has two depressions for the crucial ligaments. 

 The ONE FOE tin. wtkkiok ligament is on the posterior part of the inner sur- 

 face of thf external condyle. The one for the posterior ligament is on the 

 anterior part of the external surface of the inner condyle. The angle of the 

 neck of femur with the shaft makes no changes after growth is completed. 



Blood Supply. — The head and neck of the femur receive branches from 

 the sciatic, obturator and circumflex arteries. The trochanter receives twigs 

 from the circumflex arteries. The nutrient vessel for the shaft is derived from 

 second perforating; it enters near the linea aspera and is directed towards the 

 head of the bone. Condyles are nourished by articular branches from the 

 popliteal and the anastomotic of femoral. 



Ossifk \'i ION. - From five centers. The one for the shaft is a primary 

 center and begins to ossify in the seventh week of intra-uterine life. The 

 other four are epiphyseal centers. The one for the lower extremity appears in 

 the NINTH MONTH and joins the bone in the twentieth year. This is the only 

 epiphysis which ossifies before birth, although some observers say the proxifhal 

 end of the tibia ossifies before birth. The one for the head appears in the first 

 yi.ai; and joins the bone in the nineteenth year. The one for the greater tro- 

 chanter appears the fourth yi.ai; and joins the bone in the eighteenth year. 



The • for the lesser trochanter appears in the thirteenth or fourteenth 



i eab and join- the bone the seventeenth year. 



Articulates.- With three bones: os innominatum, tibia and patella. 

 \ii M HMENT "i MuS( LES. — Twenty-three. To the great trochanter, the 

 Gluteus medius, Gluteus minimus, Pyriformis, Obturator externus. Obturator 

 interim.-. Gemellus superior, Gemellus inferior, and Quadratus femoris. To 

 the lesser trochanter, the Psoas magnus and the Iliacus below it. To the shaft, 

 tin' Vastus externus, Gluteus maximus, short head of Biceps, Vastus internus, 

 Adductor magnus, Pectineus, Adductor brevis, Adductor longus, Crureus and 

 Subcrureus. To the condyles, the Gastrocnemius, Plantaris and Popliteus. 



