THE LOWER LIMB 599 



should now be studied as far as the upper border of the adductor longus, 

 and this will be facilitated by dividing the corresponding vein. Its external 

 circumflex branch should be followed out in its ascending, transverse, and 

 descending branches, and the anastomoses of these branches should be care- 

 fully studied. An articular offset to the hip-joint from the ascending branch 

 should be looked for. The long descending branch of this artery to the 

 geniculate arterial rete should be noted. 



The branches of the anterior or superficial and posterior or deep divisions 

 of the anterior femoral nerve should be dissected, and the following articular 

 nerves should be looked for, namely, one to the hip-joint from the nerve 

 to the rectus femoris, and three to the knee-joint, as follows : one from the 

 nerve to the vastus extemus ; one from the most internal of the branches 

 to the crureus, supplying in its course the subcrureus ; and one from the 

 nerve to the vastus intemus, which ultimately accompanies the deep branch 

 of the arteria anastomotica magna. 



The vastus extemus, crureus, and vastus intemus are next to be dissected. 

 The vastus intemus and crureus are to be separated by dissecting along the 

 course of a cellular interspace, which extends upwards in the direction of 

 a line drawn from the inner border of the patella to the inferior cervical 

 tubercle of the femur. When the vastus intemus is reflected inwards, a 

 bare strip along the inner aspect of the shaft of the femur, devoid of muscular 

 fibres, is to be noted. The crureus should next be turned aside in two halves 

 by making a vertical incision down the centre of the muscle. This will show 

 the lower Umit of origin of the muscle, and it will bring into view the sub- 

 crureus. The bursa beneath the suprapatellar tendon and the prolongation 

 of the synovial membrane of the knee-joint, which is continuous with it, 

 should be shown. In dissecting the lower part of the vastus intemus the 

 deep branch of the arteria anastomotica magna and an articular branch to 

 the knee-joint from the nerve to the vastus intemus should be followed out. 



The pectineus and adductor longus should be divided and reflected. 

 When the pectineus has been reflected it should be noted that a portion of 

 the capsular ligament of the hip-joint (including the pubo-femoral hgament) 

 is exposed. This will bring fully into view the adductor brevis, with the 

 anterior or superficial division of the obturator nerve resting upon it, and 

 the obturator extemus lying above it. The continuation of the arteria 

 profunda femoris is also exposed. The four perforating branches of this 

 vessel should be shown, the first and second piercing the adductor brevis and 

 adductor magnus, whilst the third and fourth pierce only the adductor 

 magnus. 



The internal circumflex artery should be studied at this stage. Replacing 

 the pectineus, the artery should be traced backwards between that muscle 

 and the psoas magnus, and then between the adductor brevis and obturator 

 extemus. In this latter situation the artery should be shown to divide into 

 its two terminal branches, namely, (a) ascending, or anterior, passing with 

 the obturator extemus to the digital fossa ; and (b) transverse or posterior, 

 passing backwards between the quadratus femoris and upper border of the 

 adductor magnus, and furnishing in its course an articular branch to the 

 hip-joint which enters beneath the transverse hgament. It should be observed 

 that the internal circumflex artery gives branches to the obturator ex- 

 temus, which anastomose in that muscle with branches of the obturator 

 artery. 



The adductor brevis should be divided without injuring the anterior division 

 of the obturator nerve, and the obturator extemus should be dissected. Its 

 relation to the neck of the femur and the capsular ligament should be noted, 

 as also its relation to the obturator nerve. This nerve is now to be dissected. 

 An articular branch to the hip-joint from the anterior division should be looked 

 for, and the termination of this division in cutaneous and vascular branches 

 should be noted. The posterior division should be followed out in the 

 expectation of finding it terminating in the inconstant geniculate branch. 

 An accessory obturator nerve may be found emerging over the superior pubic 

 ramus beneath the pectiueus,i after which it wiU be seen to end in thceq 



