1452 



CLINICAL AND TOPOGRAPHICAL ANATOMY 



prominence also gives attachment to the fibular collateral ligament, which splits the tendon 

 into two parts. Behind is the apex (styloid process) from which the posterior part of the 

 fibular collateral ligament arises. Parallel and close to the medial border of the tendon, the 

 peroneal nerve descends, as a rounded cord, to cross the neck of the fibula and enter the peroneus 

 longus. In tenotomy of the biceps an open incision should be employed to avoid injury to 

 the nerve and insure the division of any contracted fascial bands. On the medial side the ten- 

 dons are thus arranged : Nearest to the middle of the popliteal space is the long and more slender 

 tendon of the semi-tendinosus; next, the thicker tendon of the semi-membranosus; this and the 

 graciUs, which comes next, appear as one tendon, but by a little manipulation the finger can be 

 made to sink into the interval between the semi-membranOsus, with its thick rounded border 

 laterally and the gracilis medially. The sartorius can easily be thrown into relief on the medial 

 side of the joint by telling the patient to raise the leg extended, the limb being rotated laterally 

 and one leg crosses over the other. 



Popliteal vessels. — The artery traverses this space from above downward, 

 appearing beneath the semi-membranosus, a little to the medial side of the middle 

 line, and then passing down in the centre of the space to the interval between the 

 gastrocnemii. Its course corresponds with a line drawn from the medial side of the 



Fig. 1169. — Deep View of the Popliteal Space. (Hirschfeld and Leveill^.) 



Adductor magnus 



Popliteal vein 



Popliteal artery 



Tibial nerve 



Vastus medialis 



Superior medial articular artery 



Tendon of semi-membranosus 



Medial head of gastrocnemius 

 Inferior medial articular artery 

 Popliteal vein 

 Popliteus 



Tendon of plantaris 



Vastus lateralis 

 Sciatic nerve 



Short head of biceps 



Peroneal nerve 



Long head of biceps, cut 

 Lateral head of gastrocnemius 



Lateral cutaneous crural nerve 



Soleus 



Gastrocnemius 



Small saphenous vein and nerve 



\ 



hamstrings to the centre of the lower part of the space. The artery bifurcates on 

 the level of a line corresponding to the tuberosity of the tibia. It lies on the pop- 

 liteal surface of the femur, the oblique popliteal ligament and the popliteus. It 

 is the second of these structures which usually prevents popliteal aneurism and 

 abscess from making their way into the joint. 



The popliteal vein, intimately adherent to the artery, lies to the lateral side above, but 

 crosses to its niodial side below. The i)oi)liteal sheath is also unusually strong. The tibial 

 nerve crosses the artery in the .same direction as the vein, by which it is separated from the 

 artery. This rx-rve is the direct continuation of the s(!iatic nerve (fig. 1109), and enters more into 

 the space than its fellow branch. The close relation of the vein and nerve explains the early 

 8tifTne.ss of the knee, the pains below, often called 'rheumatic,' and the cedema, in popliteal 

 aneurism; also the pulsation of swellings not anein-ismal. 



The superior articular arteries (fig. 1169) course laterally and medially immediately above 

 the femoral coiidylos; the way in which they cling closely to the bone here is one provision to pre 

 vent overstretcliing of t he artery ; the inferior ones lie just above the head of the fibula and below 

 the medial condyle of the tibia (fig. 1109). The deep part of the geiui suprema artery runs in 

 front of the tendon of the adductor niagiuis; the sni)orficial with tlie saphenous nerve. 



The popliteal artery may be ligatured — (A) Behind, in the upi)er part of the popliteal 

 space, just after its emergence from under the semi-membranosus. Here, for a short space 



