46 SUPERFICIAL ANATOMY OF THE LOWER LIMB. 



lower part of the leg on the opposite knee, when the inner tuberosity of the tibia 

 projects beyond the inner condyle of the femur. On the upper part of the inner 

 condyle, the sharp adductor tubercle and the insertion of the adductor magnus 

 tendon are also to be recognized. The external condyle, although not generally 

 prominent, is subcutaneous and readily felt ; its tuberosity is comparatively little 

 developed. The outer tuberosity of the tibia, on the other hand, forms a marked 

 prominence at the outer and fore part of the knee, about an inch below the joint ; 

 and behind this, at a slightly lower level, viz., that of the tubercle of the tibia, 

 the head of the fibula is distinctly felt at the outer and back part of the limb, where 

 it generally corresponds to a depression, when the joint is extended, between the 

 tendon of the biceps above and the peroneus longus muscle below : it often forms 

 a prominence, however, when the knee is flexed. Anteriorly, the patella is sub- 

 cutaneous, and its lateral margins are distinctly seen. When the extensor muscles 

 are relaxed, the patella can be easily moved from side to side ; but if these muscles 

 are contracted, the patella is drawn upwards and pressed firmly against the end of 

 the femur, and the ligamentum patellae can then be followed down to the tubercle of 

 the tibia : on each side of the ligament is a soft eminence produced by the infra- 

 patellar mass of fat. When the knee is bent, the patella sinks into the hollow 

 between the tibia and the femur, and the articular surface of the latter bone is in 

 great part exposed ; the trochlear surface can then be distinctly traced, although 

 covered by the tendon of the extensor muscle. The upper and outer angle of 

 this surface forms a useful landmark ; and a line drawn from it to the adductor 

 tubercle on the internal coudyle marks the upper limit of the epiphysis of the lower 

 end of the femur. There are generally two bursae, a superficial one and a deep 

 one, over the patella, and there is frequently another over the tubercle of the tibia 

 (Vol. II, p. 242). 



At the back of the knee is the ham, which is marked by a deep hollow when the 

 joint is flexed, but by a slight elevation when it is extended. On each side are the 

 tendinous hamstrings ; internally the slender semitendinosus and the stronger semi- 

 membranosus are to be recognized, as well as the gracilis a little farther forwards ; 

 externally is the thick tendon of the biceps leading down to the head of the fibula. 

 Immediately in front of the biceps tendon, when the joint is a little bent, the upper 

 part of the external lateral ligament is to be detected ; and between this and the 

 outer margin of the patella, the lower end of the ilio-tibial band appears as a strong 

 cord beneath the skin, running down on the outer side of the knee to the prominent 

 external tuberosity of the tibia ; while on the inner side, the sartorius tendon, with 

 the subjacent tendons of the gracilis and semitendinosus, forms a slight elevation as 

 it curves forwards below the inner tuberosity, to be inserted close to the tubercle of 

 the tibia. 



The external saphenous vein enters the lower part of the ham in the middle 

 line of the limb, and perforates the fascia to join the popliteal vein ; but it is not 

 usually visible on the surface. The internal saphenous vein is generally seen on the 

 inner side of the knee, and the nerve of the same name meets it behind the internal 

 tuberosity. 



The popliteal vessels enter the ham somewhat internal to the middle line above, 

 and are then continued downwards over the centre of the back of the knee ; the 

 vein is more superficial than the artery, but both are very deeply placed. The 

 upper articular vessels run transversely inwards and outwards immediately above the 

 condyles of the femur ; and the lower articular vessels are respectively just below 

 the inner tuberosity of the tibia, and above the head of the fibula. The deep part 

 of the anastomotic artery descends to the knee along the front of the adductor 

 magnus tendon. 



