270 IMPORTANT ANATOMICAL LANDMARKS. 



tains the aperture called Hunter's canal, through which 

 the femoral artery passes to reach the popliteal space. 

 This orifice may sometimes be felt by the finger. 



The patella rests upon the condyles of the femur. The 

 tendon of the triceps extensor muscle, and the ligament 

 of the patella below, divide the articulation of the knee 

 into two lateral halves, and the expansion of the patella 

 laterally, divides it, to a certain extent, transversely. If 

 there is any increase of the synovial fluid, the fulness of 

 the capsule will be most obvious above and below the 

 patella, on each side of the tendon and of the ligament. 

 The articulation will consequently have a quadrilateral 

 shape, with four projections corresponding to the above- 

 mentioned localities. 



The trochanter major, when the thigh is rotated, describes 

 an arc of a circle, the radius of which is equal to the length 

 of the head and neck of the femur. The inner condyle be- 

 ing on the same plane as the head of the bone, indicates 

 always the direction which the latter assumes. 



The sciatic nerve follows a course indicated by a line 

 drawn from a point, midway between the trochanter major 

 and the tuberosity of the ischium, to the upper angle of 

 the popliteal space. 



The popliteal 'space is a diamond-shaped depression at 

 the posterior aspect of the knee-joint. Its lower sides are 

 formed by the prominences of the two separated muscular 

 bellies by which the gastrocnemius muscle arises. Its 

 upper and outer side is formed by the lower extremity of 

 the biceps muscle. Its upper and inner side is formed by 

 the following four muscles, enumerated in their order from 

 within outward ; semi-membranosus, semi-tendinosus, gra- 

 cilis, and sartorius. 



The popliteal artery, extending from the opening in the 

 tendon of the adductor magnus, to the upper border of the 

 soleus muscle, follows a line, a little oblique, from within 

 outward, but corresponding, in a general way, to the long 

 axis of the popliteal space. It is, however, a trifle nearer 

 its inner than its outer side. The artery lies too deep for 

 its pulsations to be felt. It should be noticed that when 

 the leg is flexed, a bullet might traverse 'the popliteal 

 space, or the ham-strings be divided, without wounding 

 the popliteal artery; but that this could not happen when 

 the limb is straight and extended as in the erect position. 



The anterior tibial artery, in the leg, follows a course 



