Reproductive and Genitourinary System PDF

Ligaments of the Pelvis Sacroiliac ligaments - secures the sacroiliac joint ○ Anterior sacroiliac ligament ○ Posterior sacroiliac ligament ○ Interosseous sacroiliac ligament Pubic ligaments - join the pubic symphysis ○ Superior pubic ligament ○ Inferior pubic ligament...

Ligaments of the Pelvis Sacroiliac ligaments - secures the sacroiliac joint ○ Anterior sacroiliac ligament ○ Posterior sacroiliac ligament ○ Interosseous sacroiliac ligament Pubic ligaments - join the pubic symphysis ○ Superior pubic ligament ○ Inferior pubic ligament Sacrospinous ligament ○ Extends from the sacrum → ischial spine Sacrotuberous ligament ○ Extends from the sacrum → ischial tuberosity Muscles of the Pelvic Wall and Floor Boundary Muscle Attachments Innervation Action Lateral Obturator Pelvic surfaces of ileum, ischium Nerve to obturator Rotates thigh wall internus and obturator membrane → greater internus (L5, S1, S2) laterally trochanter Postero-su Piriformis S2-S4 vertebrae → superior margin Anterior rami of S1 Rotates thigh perior wall of greater sciatic notch and and S2 laterally sacrotuberous ligament Floor Coccygeus Ischial spine → inferior end of S4 and S5 Flexes coccyx coccyx Levator ani Body of pubis, tendinous arch of Pudendal nerve Forms most of the (pubococcyge obturator fascia and ischial spine → (S2, S3, S4) and pelvic diaphragm us, perineal body, coccyx, anococcygeal anterior rami of S4 which supports the iliococcygeus, ligament pelvic viscera and puborectalis, resists increases in pubvaginalis) intra-abdominal pressure Pelvic Diaphragm The pelvic floor/ diaphragm is a bowl-shaped structure composing of muscle fibres of the levator ani and the coccygeus muscles (and associated connective tissue) Separates the true pelvis superiorly from the perineum inferiorly Levator Ani and Coccygeus Puborectalis U-shaped sling extending from pubic bone → pubic bone around the rectal hiatus (which transmits the anal canal) Contraction bends the anal canal in order to create the anorectal angle maintain faecal continence Defecation occurs during muscle relaxation Pubovaginalis/ Pre-rectal fibres of puborectalis m. Flanks the urogenital hiatus which transmits the urethra and the vagina Contraction preserves urinary continence Pubococcygeus Main constituent/ component of the levator ani Arises from the pubic bone and anterior part of the tendinous arch → coccyx and anococcygeal ligament Iliococcygeus Extends from ischial spines and posterior aspect of the tendinous arch → coccyx and anococcygeal ligament Elevates the pelvic floor and anorectal canal