- Superior pubic ramus
Name = Superior pubic ramus
Latin = ramus superior ossis pubis
GraySubject = 57
GrayPage = 236
Caption = Right hip bone. External surface. (Superior ramus of pubis labeled at center right.)
Caption2 = Pelvis. Superior ramus is 4b.
DorlandsPre = r_02
DorlandsSuf = 12692205
The superior pubic 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 longusarises from the upper and medial angle, immediately below the crest; lower down, the Obturator externus, the Adductor brevis, and the upper part of the Gracilistake 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 aniand 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 projects forward; the inferior crusof the subcutaneous inguinal ring(external abdominal ring), and the inguinal ligament(Poupart’s ligament) are attached to it.
Passing upward and laterally from the pubic tubercle is a well-defined ridge, forming a part of the
pectineal linewhich 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 attachment to the
inguinal falx, and to the Rectus abdominisand 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 crusof 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 foramenand 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 notchto 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" constitutes part of the anterior boundary of the
lesser pelvis. It is smooth, convex from above downward, and affords origin to some fibers of the Obturator internus.
* - "The Male Pelvis: Hip bone"
* - "Sacrum, Median Sagittal Section"
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