THE FEMUR 437 



and (3) the tendinous origin of the vastus lateralis, in the distal 

 part of the wound. Plastic operations on the neck of the femur 

 (Jones ; Murphy) and sub-trochanteric osteotomy may be carried 

 out by this route. The latter operation is performed when the 

 hip-joint is ankylosed in bad position and may consist of the 

 removal of a wedge-shaped portion or in division of the femur. 

 When flexion constitutes the more marked deformity, the 

 base of the wedge is posterior, but, when adduction is more 

 pronounced, the base is on the lateral aspect. 



After the femur has been exposed by cutting through the 

 vastus lateralis, the periosteum is divided transversely, distal 

 to the greater trochanter, and the cut edges are elevated from 

 the bone. A wedge of bone may then be removed from the 

 required site and the periosteum is stitched together again. 

 When the wound has been closed the limb is placed in the 

 best position obtainable, and is kept fixed by the necessary 

 splints. 



The Shaft of the Femur is so obscured by its muscular 

 covering that actual palpation is impossible. Thickening of 

 the shaft may be determined by grasping the thigh firmly from 

 in front so that the finger tips are inserted along the line of the 

 medial (or lateral) intermuscular septum, while the thumb is 

 inserted along the line of the lateral (or medial) intermuscular 

 septum. In comparing the circumferential measurements of 

 the two limbs it must be remembered that thickening of the 

 femoral shaft may be accompanied by atrophy of the surrounding 

 muscles, so that, although the one limb is normal and the other 

 abnormal, the measurements obtained may be practically 

 equal. 



In osteo-myelitis, incisions to expose the femoral diaphysis 

 are made along the line of the lateral intermuscular septum, as 

 few important structures intervene between the surface and 

 the bone in this situation. The incision splits the ilio-tibial 

 tract and exposes the vastus lateralis. When the wound is 

 deepened through this muscle, the vastus intermedius (crureus) 

 is exposed and may be elevated from the lateral surface of the 

 femur. If the incision is extended over the distal part of the 

 diaphysis, the vastus lateralis is retracted forwards from the 

 intermuscular septum, which is drawn backwards together with 

 the short head of the biceps. The distal part of the lateral 

 surface of the femur is thus exposed, and the anastomosis 

 between the descending branch of the lateral circumflex and 



