5^4 ^ MAIfUALOF A tf ATOMY 



of these structures will be found coursing along the upper border of the gluteus 

 minimus, and crossing outwards over its centre. The latter branch (lower) of 

 the artery should be shown to give a branch to the digital fossa to take part 

 in the digital anastomosis, and the corresponding branch of the superior gluteal 

 nerve should be followed outwards to the outer aspect of the thigh as far as 

 possible on its way to the tensor fasciae femoris, which it supplies. The 

 gluteus minimus (except its anterior fibres) is to be stripped from the bone, 

 after which the surface thereby exposed should be cleaned. The posterior 

 or reflected head of the rectus femoris is to be shown arising from the dorsum 

 ilii immediately above the brim of the acetabulum. The muscular relations 

 of the capsular ligament of the hip-joint should be carefully attended to in 

 so far as the position of the body will allow. 



Popliteal Space. — This space should be dissected before the structures on 

 the back of the thigh are disturbed. The landmarks having been studied, 

 the skin is to be removed by the following incisions : ( i ) a median vertical 

 incision extending from the junction of the upper two- thirds and lower third 

 of the thigh to the junction of the upper fourth and lower three-fourths of 

 the leg ; and (2) two transverse incisions, one at either end of the median 

 incision. 



The small sciatic nerve is to be displayed after it pierces the fascia 

 lata at the back of the knee-joint, and it should be followed to its terminal 

 distribution over the upper part of the back of the leg. The upper part of 

 the external or short saphenous vein is to be dissected, and in connection with 

 it the following two veins should be noticed : (i) a fairly large tributary 

 vessel, which descends from the lower part of the back of the thigh ; and 

 (2) a communicating branch, which passes upwards and inwards to join the 

 long saphenous vein. Three cutaneous sural arteries (branches of the popliteal) 

 may be looked for — an external, over the outer head of the gastrocnemius ; an 

 internal, over the inner head ; and a middle, accompanying the short saphenous 

 vein. The fascia lata should next be cleaned, and the accession of strength 

 which it here receives from superadded transverse fibres should be observed. 

 Above the level of the knee-joint the small sciatic nerve will be found in 

 the middle line beneath the fascia lata. This fascia is now to be removed, 

 and the boundaries of the popliteal space are to be cleaned. 



The principal contents of the space are to be displayed by the removal of 

 a large amount of fat. The great sciatic nerve should be exposed close to 

 the upper median angle, and its external and internal popliteal branches 

 cleaned downwards from that point. The external popliteal nerve is to be 

 followed along the inner border of the biceps femoris as far as a point just 

 below the head of the fibula. In cleaning this nerve, the dissector should 

 look for the following branches, namely, (i) superior articular, to accom- 

 pany the superior external articular artery ; (2) inferior articular, to accompany 

 the inferior external articular artery ; (3) lateral cutaneous, to the integument 

 of the outer side of the leg over about its upper two-thirds ; and (4) ramus 

 communicans fibularis, which passes downwards and inwards to the middle 

 line of the calf on its way to join the ramus communicans tibiaUs, and so form 

 the external or short saphenous nerve. 



The internal popliteal nerve is to be followed through the centre of the 

 space as low as the interval between the heads of the gastrocnemius. In 

 cleaning it, the following branches should be looked for : (i) superior articular 

 (inconstant), to accompany the superior internal articular artery ; (2) central 

 or azygos articular, to accompany the corresponding artery ; (3) inferior 

 articular, to accompany the inferior internal articular artery ; (4) ramus 

 communicans tibiahs, which takes a straight course downwards to the calf, 

 where it forms the chief part of the external or short saphenous nerve ; and 

 (5) four or five muscular (sural) branches, as follows : (a) one to the outer head 

 of the gastrocnemius ; (b) one to the plantaris (which sometimes comes from 

 the preceding branch) ; (c) one to the inner head of the gastrocnemius ; 

 {d) one to the soleus ; and (e) one to the popliteus. The nerve to the 

 popliteus should be preserved with great care. 



The internal popliteal nerve should be hooked to one side, and the popliteal 



