THE MALE PERIXAJUM 



lUO'J 



The perinaium is divided url)itnirily into two \K\viii Ijy a line drawn transversely 

 between the two ischial tu))erosities an inch in front of the anus. The anterior 

 portion is called the perintuuni ])roper, the posterior the isehio-rectal region. Tliis 

 line, however, does not coincide exactly with the true anatomical l»ound;iry as 

 revealed l»y dissection. 



The isehio-rectal region comprises the parts suiTouiiding tlic amis and the 

 isehio-rectal fossa*. 



The removal of the integument exi)oses the si>hincter muscle of the anus in the 

 middle line, and on each side, ht'tween this and the lateral lioimdary of the jieri- 

 na-um. the external ajx'rture of the isehio-rectal fossa. 



Tile sphincter ani externus is a voluntary muscle surrounding the anus, and 



Fi(i. 047.— The .Malic PkuiX-EIM. (Modified from Hirsclifeld and Lcveillt-.) 



BULBO-CAVERNOSUS 



Superflcial triangular ligament 

 ISCHIO-CAVERNOSUS 



ISFERWR PVDESDA L AVvA' 1 

 •SLPERFKIAL I'ERLWICAL .SERVE 



INFERIOR II.EMORRnori)AL SERVE 

 CUTASEOUa BRASCH OF FOURTH SACRAL 



Qluteus maximus 

 TUBEROSITY OF ISCHIUM 

 I Great aacro-sciatic ligament 



Levator ani 

 Superficial transversus perinci 

 Sphincter ani 



attached, in front to the tendinous centre of the perina?um (where it meets the 

 bulbo-cavernosi, the superficial transversi perina?i, and some fasciculi of the levatores 

 ani); V)ehind to the tip of the coccyx. Its fibres are closely comiected with the 

 skin, and sui)erHcial bundles pass fol•^^•ards by the sides of the anus, a few decus- 

 sating with each other acro.^^s the middle line, and .some ajtpear to cross directly 

 over to the opposite side, and around the anus as an annular sphincter. They are 

 pierced by radiating liands of the longitudinal layi-r of the muscular wall of the 

 rectum, which l)ecome lost in the <lee]» layers of the integument. 



The external sphincter is in relation superli<-iallv with the integument, deeitly 

 with the levatores ani and internal s]»]iincter; on the outer side witli the fat of the 

 isehio-rectal fossa; and internally with the lower )»ortioni>f the 'internal sphincter' 

 (a thickening of the cinular muscle of the rectum ). ami to a small extent with the 



