APPLIED ANATOMY OF THE LOWER EXTREMITY 



547 



l>v the weight of the limb rotating it outward. The shortening is produced by the action of the 

 Glutei, and by the Rectus femoris in front and the Biceps, Semitendinosus, and Semimem- 

 branosus behind. 



In fracture of the femur just below the trochanters (Fig. 404) the upper fragment, the portion 

 chiefly displaced, is tilted forward almost at right angles with the pelvis by the combined action 

 of the Psoas and Iliacus, and, at the same time, everted and drawn outward by the external 

 Rotator and Glutei muscles, causing a marked prominence at the upper and outer side of the 

 thigh, and much pain from the bruising and laceration of the muscles. The limb is shortened, 

 in consequence of the lower fragment being drawn upward by the Rectus in front, and the Biceps, 

 Semimembranosus, and Semitendinosus behind, and is at the same time everted. This fracture 

 may be reduced by direct relaxation of all the opposing muscles, to effect which the limb should 

 be put up in such a manner that the thigh is flexed on the pelvis and the leg on the thigh. 



SEMI- 

 CMBRANOSUS. 



SEMI- 

 TENDINOSUS. 



FIG. 404. Fracture of the femur 

 below the trochanters. 



FIG. 405. Fracture of the femur 

 above the condyles. 



FIG. 406. Fracture of 

 the patella. 



Oblique fracture of the femur immediately above the condyles (Fig. 405) is a formidable injury, 

 and attended with considerable displacement. On examination of the limb the lower frag- 

 ment may be felt deep in the popliteal space, being drawn backward by the Gastrocnemius 

 and Plantaris muscles, and upward by the Hamstring and Rectus femoris muscles. The pointed 

 end of the upper fragments is drawn inward by the Pectineus and Adductor muscles, and tilted 

 forward by the Psoas and Iliacus, piercing the Rectus muscle and occasionally the integument. 

 The greatest care is requisite in keeping the pointed extremity of the upper fragment in proper 

 position; otherwise, after union of the fracture, the power of extension of the limb is partially 

 destroyed from the Rectus femoris muscle being held down by the fractured end of the bone, 

 and from the patella, when elevated, being drawn upward against the projecting fragment. 



In fracture of the patella (Fig. 406) the fragments are separated by the effusion which takes 

 place into the joint, and by the action of the Quadriceps extensor; the extent of separation of 

 the two fragments depending upon the degree of laceration of the ligamentous structures around 

 the bone. 



The tibia is fractured most commonly by indirect force at the junction of the middle third 

 with the lower third of the shaft. Compound fractures are more common in the leg than 



