THE GLUTEAL REGION. 239 



boundary of the region of the hip, and comprises the 

 obturator foramen, the structures covering it on either 

 surface, and the parts immediately adjacent. The bony 

 prominences are easily felt; they are the pubic space and 

 horizontal ramus of the pubes anteriorly, and the de- 

 scending ram us and tuberosity of the ischium internally 

 and behind. The anterior surface consists of the gra- 

 cilis, pectineus and adductors, beneath which is the ob- 

 turator interims. The obturator foramen is not entirely 

 filled in by the membrane, being wanting just below the 

 groove through which the obturator artery and nerve 

 pass. Attached to the inner or pelvic surface of the 

 membrane and to the bone around, is the obturator* in- 

 tern us, having the obturator fascia below, between it and 

 the levator ani, and the peritoneum above; it is inti- 

 mately connected with the margins of the obturator 

 membrane, and assists in forming the obturator canal. 

 This obturator canal is about three-quarters of an inch 

 in length, and directed obliquely from above downwards, 

 and from without inwards. 



Obturator Hernia. Occasionally a hernia protrudes 

 through the canal, and forms a swelling in the adductor 

 or pubic region, emerging upon the thigh, below the 

 horizontal ramus of the pubes, to the inner side of the 

 capsule of the hip-joint, having the femoral vessels in 

 front, and a little to the outer side, the tendon of the 

 adductor longus to the inner side, and behind, the pec- 

 tineus muscle. The obturator vessels and nerve also 

 pass through it to the thigh, and the pressure exerted by 

 the hernia upon the nerve induces pain in those regions 

 to which it is supplied, and is a feet of importance in 

 diagnosis. 



