236 OSTEOLOGY 





Transversus perimri is attached, and in front of this a portion of the cms penis 

 vel clitoridis and the Ischiocavernosus. Its lateral border is thin and sharp, a ad 

 forms part of the medial margin of the obturator foramen. 



The Pubis (os pubis) . The pubis, the anterior part of the hip bone, is divisible 

 into a body, a superior and an inferior ramus. 



The Body (corpus oss. pubis). The body forms one-fifth of the acetabulum, 

 contributing by its external surface both to the lunate surface and the acetabular 

 fossa. Its internal surface enters into the formation of the wall of the lesser pelvis 

 and gives origin to a portion of the Obturator internus. 



The Superior Ramus (ramus superior oss. pubis; ascending ramus}. The superior 

 ramus extends from the body to the median plane where it articulates with its 

 fellow of the opposite side. It is conveniently described in two portions, viz., a 

 medial flattened part and a narrow lateral prismoid portion. 



The Medial Portion of the superior ramus, formerly described as the body of 

 the pubis, is somewhat quadrilateral in* shape, and presents for examination two 

 surfaces and three borders. The anterior surface is rough, directed downward and 

 outward, and serves for the origin of various muscles. The Adductor longus arises 

 from the upper and medial angle, immediately below the crest; lower down, the 

 Obturator externus, the Adductor brevis, and the upper part of the Gracilis take 

 origin. The posterior surface, convex from above downward, concave from side 

 to side, is smooth, and forms part of the anterior wall of the pelvis. It gives origin 

 to the Levator ani and Obturator internus, and attachment to the puboprostatic 

 ligaments and to a few muscular fibers prolonged from the bladder. The upper 

 border presents a prominent tubercle, the pubic tubercle (pubic spine), which pro- 

 jects forward ; the inferior crus of the subcutaneous inguinal ring (external abdominal 

 ring), and the inguinal ligament (Poupart's ligament) are attached to it. Passing 

 upward and laterahvard from the pubic tubercle is a well-defined ridge, forming 

 a part of the pectineal line which marks the brim of the lesser pelvis: to it are 

 attached a portion of the inguinal falx (conjoined tendon of Obliquus internus 

 and Transversus), the lacunar ligament (Gimbernat's ligament), and the reflected 

 inguinal ligament (triangular fascia). Medial to the pubic tubercle is the crest, 

 which extends from this process to the medial end of the bone. It affords attach- 

 ment to the inguinal falx, and to the Rectus abdominis and Pyramidalis. The 

 point of junction of the crest with the medial border of the bone is called the angle ; 

 to it, as well as to the symphysis, the superior crus of the subcutaneous inguinal 

 ring is attached. The medial border is articular; it is oval, and is marked by eight 

 or nine transverse ridges, or a series of nipple-like processes arranged in rows, 

 separated by grooves; they serve for the attachment of a thin layer of cartilage, 

 which intervenes between it and the interpubic fibrocartilaginous lamina. The 

 lateral border presents a sharp margin, the obturator crest, which forms part of the 

 circumference of the obturator foramen and affords attachment to the obturator 

 membrane. 



The Lateral Portion of the ascending ramus has three surfaces : superior, inferior, 

 and posterior. The superior surface presents a continuation of the pectineal line, 

 already mentioned as commencing at the pubic tubercle. In front of this line, the 

 surface of bone is triangular in form, wider laterally than medially, and is covered 

 by the Pectineus. The surface is bounded, laterally, by a rough eminence, the 

 iliopectineal eminence, which serves to indicate the point of junction of the ilium 

 and pubis, and below by a prominent ridge which extends from the acetabular 

 notch to the pubic tubercle. The inferior surface forms the upper boundary of 

 the obturator foramen, and presents, laterally, a broad and deep, oblique groove, 

 for the passage of the obturator vessels and nerve; and medially, a sharp margin, 

 the obturator crest, forming part of the circumference of the obturator foramen, 

 and giving attachment to the obturator membrane. The posterior surface consti- 



