THE REGION OF THE KNEE 443 



its mid-point corresponds to the level of the knee-joint. On 

 each side of the ligamentum patellae a slight triangular depression 

 can be seen when the knee is semi-flexed. The lateral depression 

 is bounded distally by the anterior margin of the proximal 

 extremity of the tibia, laterally by the margin of the articular 

 surface of the femur , and medially by the ligamentum patellae. 



The medial depression is bounded by the corresponding 

 parts of the femur, tibia, and patellar ligament. Palpation 

 of the collateral boundaries of these depressions readily reveals 

 the presence of lipping of the femoral condyles in rheumatoid 

 arthritis. Aspiration of the knee-joint may be carried out 

 through either of these areas, but when the joint is distended 

 with fluid, the surface depressions are no longer visible. 



The tibial tuberosity (tubercle) can easily be palpated ; it 

 lies one inch distal to the line of the knee-joint. The head of the 

 fibula is placed on the same level as the tibial tuberosity, but on 

 a plane posterior to it. It serves as a guide to the common 

 peroneal (ext. popliteal) nerve, which can be rolled against the 

 bone as it crosses the lateral aspect of the fibular neck. 



The lateral aspect of the lateral condyle and the medial 

 aspect of the medial condyle of the femur are both subcutaneous. 

 The adductor tubercle is the most proximal palpable point on the 

 medial condyle, and when the knee is semi-flexed the tendon of 

 the adductor magnus can be traced proximally from it. 



In active extension of the knee-joint the tendon of the 

 rectus femoris forms a tense band, ij inches wide, which is 

 inserted into the proximal border of the patella. In the same 

 position of the limb the vastus medialis forms a prominent 

 elevation to the medial side of the tendon, and the vastus lateralis 

 forms a similar elevation on the lateral side but it is placed at a 

 more proximal level. A very definite depression lies immediately 

 distal to the elevation produced by the vastus lateralis ; it is 

 bounded medially by the rectus femoris and laterally by the 

 ilio-tibial tract. The latter forms a distinct ridge, which crosses 

 the antero-lateral aspect of the joint and can be traced distally 

 to its attachments on the lateral condyle of the tibia and the 

 head of the fibula. 



When the knee is flexed against resistance, the tendons of 

 the hamstrings are rendered prominent and can be palpated 

 almost to their respective insertions. The tendon of the semi- 

 membranosus is felt on the medial side of the tendon of the 

 semitendinosus , which, however, is more superficial. On the 



