296 THE INFERIOR EXTREMITY 



branch of the profunda artery pierces the adductor magnus 

 close to the distal part of the gluteal tuberosity of the femur. 



Nervus Glutaeus Inferior. The inferior gluteal nerve is 

 the nerve of supply to the glutaeus maximus. It springs 

 from the sacral plexus, and enters the gluteal region through 

 the lower part of the great sciatic foramen. When the 

 glutaeus maximus was reflected the nerve was seen breaking 

 up into numerous twigs which entered the deep surface of 

 the muscle. 



Arteria G-lutaea Inferior (O.T. Sciatic). The inferior 

 gluteal artery, a branch of the hypogastric artery (O.T. in- 

 ternal iliac), issues from the pelvis, through the great sciatic 

 foramen, below the piriformis muscle, and proceeds distally, 

 with the sciatic nerve, under cover of the glutaeus maximus, 

 in the hollow between the greater trochanter and the ischial 

 tuberosity. At the lower border of the glutaeus maximus it 

 is continued, as a fine cutaneous twig, to the posterior aspect 

 of the thigh, in company with the posterior cutaneous nerve. 

 It gives off numerous branches in the gluteal region. Of 

 these the large muscular offsets to the glutaeus maximus, and 

 the cutaneous twigs that accompany the branches of the 

 posterior cutaneous nerve of the thigh which turn round the 

 distal border of that muscle, have been already studied. The 

 following three branches remain to be examined : ( i ) the 

 coccygeal branch, which passes medially between the sacro- 

 tuberous and sacro-spinous ligaments to reach the integument 

 and fascia in the region of the coccyx; a number of twigs 

 derived from this branch have been previously noticed piercing 

 the sacro- tuberous ligament and ending in the glutaeus 

 maximus ; (2) arteria comitans nervi ischiadici, a minute artery, 

 which runs distally on the sciatic nerve and finally penetrates 

 into its substance ; (3) the artery to the quadratus femoris, 

 which accompanies the nerve to that muscle ; it will be found 

 lying on the hip bone under cover of the sciatic nerve. 



In a well-injected body the anastomosis between the 

 inferior gluteal artery, the two terminal branches of the 

 medial circumflex artery, and the first perforating artery may 

 be made out. 



Nervus Cutaneus Femoris Posterior (O.T. Small Sciatic 

 Nerve). The posterior cutaneous nerve of the thigh arises, 

 within the pelvis, from the sacral plexus. After escaping 

 through the greater sciatic foramen it extends distally, with the 



