الحوض | Pelvis скачать в хорошем качестве

الحوض | Pelvis

تشريح الحوض anatomy of the pelvis The bony pelvis is formed by the sacrum, coccyx, and two hip bones or innominate bones . The sacrum is a triangular-shaped bone formed by the fusion of five vertebral segments. The first sacral segment has a prominent ridge located on the anterior surface of the body termed the sacral promontory, which acts as a bony landmark separating the abdominal cavity from the pelvic cavity . The transverse pro- cesses of the five sacral segments combine to form the lateral mass (ala), which articulates with the hip bones at the sacroiliac joints . The lateral mass contains sacral foramina that allow for the passage of sacral nerves . Articulating with the fifth sacral segment is the coccyx, which consists of three to five small fused bony segments. The hip bones are made up of three bones: the ilium, pubis, and ischium . Ilium. The ilium, the largest and most superior portion, consists of a body and a large winglike projection called the ala . The concave, anterior surface of the ala is termed the iliac fossa, which is separated from the body by the arcuate line. This arch-shaped line, which is located on the anterior surface of the ilium, forms part of the pelvic brim . The superior ridge of the ala is termed the iliac crest; it slopes down to give rise to the superior and inferior iliac spines. on both the anterior and posterior surfaces . The body of the ilium creates the upper portion of the acetabulum, which is a deep fossa that articulates with the head of the femur . Pubis. The pubis, or pubic bone, forms the lower anterior portion of the acetabulum and consists of a body and superior and inferior pubic rami. The bodies of the two pubic bones meet at the midline to form the pubic symphysis . The superior pubic ramus projects inferiorly and medially from the acetabulum to the midline of the body . Located on the upper surface of the superior pubic ramus is a ridge termed the pectineal line, which is continuous with the arcuate line of the ilium, forming the pelvic brim . Also on the superior surface is the pubic tubercle, which is the attachment site for the inguinal ligament . The inferior pubic ramus projects inferiorly and laterally from the body to join the ischium at an indistinct point; therefore the two together are often referred to as the ischiopubic ramus. Ischium. The ischium is the inferior portion of the hip bones and, like the pubis, is composed of a body and two rami. The body of the ischium forms the lower posterior portion of the acetabulum . The superior ischial ramus extends posteriorly and inferiorly to a roughened, enlarged area termed the ischial tuberosity. From the ischial tuberosity, the inferior ischial ramus extends anteriorly and medially to join the inferior pubic ramus. The ischial spine projects from the superior ischial ramus between two prominent notches on the posterior surface of the hip bones . The greater sciatic notch extends from the posterior inferior iliac spine to the ischial spine, and the lesser sciatic notch extends from the ischial spine to the ischial tuberosity . The two notches are spanned by ligaments that create foramina for the passage of nerves and vessels. The union of the pubic rami and ischium creates a large aperture termed the obturator foramen, which is enclosed by the obturator muscles