THE SACRAL I'LEXCS 



945 



It is also behind the coils of intestine, the lower part of the ilio-pelvic colon lying in 

 front of the left plexus, and the lower part of the ileum in front of the right plexus. 



The l>nmche> given off by this plexus are: collateral, visceral, cutaneous, and 

 muscular. 



The collateral branches are visceral, muscular, and cutaneous offsets. 



Visceral Branches are given off from the second, third, and fourth sacral nerves 

 to the pelvic viscera. Both the collateral and visceral branches of the plexus are 

 relatively small and are seldom given special names. 



Fio. 692. LUMBO-SACRAL PLEXUS. (After Toldt, "Atlas of Human Anatomy," Rebman, 



London and New York.) 



LUMBAR VERTEBRA I 



Medial orus of diaphragm 



I.I'M HA RJ (A KTER10R BRA N< 'II ) 

 MI'scuj.ARBRAXCn 



Psoas minor 

 INTERCOSTAL. YH ^ 

 Quadratus lumborum s 



ILIO-ll YPOGASTBK 

 ILIO-INGUINAL 

 Psoas major 



Transveraus 

 abdominla 



GEXITO - 

 FEMORAL 



LA TERA L . 

 CUTANEOUS 



FEMORAL - 



Iliopectineal fascia f ^t 



OBTURATOR -^O 



SUPERIOR GLUTEAL > 

 Obturator fasci 



Piriformis with ita muscular branch 



GANGLION COCCYGEUM IMPA R 

 COCCYGEAL 



ANO-COCCYUEAL 



- LA TF.RAL 

 CUTAX KOI'S 



> MI'sruLAR 

 liltAXI'HES 

 FOR1LIACUS 



FEMORAL 



LUMBAR V 



' % OBTURA TOR 

 . LUJUBO-SAI'KAL 

 TRUXK 



Piriformis 



\ -^ " SACRAL PLEXUS 



^POSTERIOR CUTANEOUS 



\ MIDDLE HJEMQRRHOIDAL 



AX 1> IXFKRKlR VKS1CAL 

 Pl'DEXDAL PLEXUS 



SACRAL 1V 



Cutaneous branches. (o) The Posterior Femoral Cutaneous (small sciatic) 

 nerve arises partly from the anterior and partly from the posterior branches of the 

 anterior primary divisions of the first, second, and third sacral nerves. It lies on the 

 back of the plexus (figs. 692, 693), leaves the pelvis at the lower border of the pirifor- 

 mis, and descends in the buttock between the glutens maximus and the posterior 

 surface of the seiatic nerve (fig. 694). At the lower border of the glutens maximus it 

 passes behind the long head of the biceps femoris, and descends, immediately be- 

 neath the deep fascia, through the thigh and the upper part of the popliteal space 



