Chapter 2 Review Williams Obstetrics Felicia Katz 8/10/11 Maternal Anatomy Chapter 2 Review Williams Obstetrics Felicia Katz 8/10/11

Anterior Abdominal Wall Langer lines: transverse incisions have less tension, better cosmesis. Camper’s and scarpa’s: find pictures?

Rectus sheath: below arcuate line two layers: internal oblique and external oblique

Above arcuate line: fascia in three layers (internal oblique layer splits into two)

Blood Supply Femoral artery branches External Iliac branches Superficial epigastric External pudendal Supply skin and subcutaneous tissue over lower abdominal wall and mons External Iliac branches Inferior epigastric vessels Supply muscles and fascia of lower abdominal wall Superficial epigastric vessels encountered when performing pfannenstiel incisions

Innervation T7-12 Ilioinguinal (L1) Iliohypogastric (L1) Skin of lower abdominal wall, upper portion of labia majora, and inner thigh Iliohypogastric (L1) Skin over suprapubic area Course between layers of rectus sheath lateral to rectus muscle Picture of dermatomes and nerve course

External Genitalia Labia majora: outer surface with hair, inner surface hairless with sebaceous glands; dense connective tissue with venous plexus – pregnancy hemorrhoids Labia minora: non-keratinized beyond “Hart line”; numerous sebaceous glands

Vagina Non-keratinized squamous epithelium, smooth muscle layer Upper 1/3 mullerian derived Lower 2/3 urogenital sinus derived Lubricated by transudate across subepithelial capillary plexus

Vascular Supply Proximal portion supplied by cervical branch of uterine artery Remainder by vaginal artery (variable origin) Lower third and vulva lymphatics drain to inguinal nodes; remainder iliac nodes

Anterior and Posterior Triangles Bulbocavernosus muscles aid in clitoral erection Vestibular bulb corresponds to corpus spongiosum of penis = aggregate of veins; may rupture to result in vulvar hemorrhage during childbirth; closed fascial compartment Posterior: no fascial separation between right and left fossae: infection and malignancy can spread bilaterally Pudendal artery

Anus IAS: constant resting tone for fecal continence; may be torn with 4th deg lacs Anal cushions: venous plexus; cause of hemorrhoids Dentate line: external hemorrhoids painful 2/2 innervated stratefied squamous epithelium

Uterus Posterior aspect covered by visceral peritoneum (serosa) Lower portion of anterior wall adjacent to bladder (dissected during c/s) Nulliparous 6-8cm; multiparous 9-10cm Majority of muscle fibers located at fundus, and at anterior and posterior walls as compared to lateral walls Innervation T11/T12 transmit pain sensation from contractions Pudendal nerve transmits pain from lower vagina and skin Figure 2.8, figure 2.15

Cervix Squamous epithelium on ectocervix Columnar epithelium on endocervix Pic of cerivx

Endometrium

Ligaments

Blood Supply

Blood Supply Uterine artery Ovarian artery Branch of internal iliac Courses along base of broad ligament toward cervix then branches in two and runs along uterine wall Crosses over ureter 2cm from cervix Ovarian artery Direct branch from aorta Enters broad ligament through IP ligament Anastamoses with branch of uterine artery Fig 2.15

Pelvic Bony Anatomy Figure 2.19

Pelvic Inlet Posterior boundary = sacral promontory Anterior boundary = pubic symphysis Lateral boundary = linea terminalis Measure adequacy of inlet via the obsetrical conjugate (subtract 1.5-2cm from diagonal conjugate)

Pelvic inlet Fig 2.20, fig 2.21

Mid-Pelvis Ischial spines (10cm) Fig 2.22

Outlet Posterior boundary = coccyx Anterior boundary = pubic arch Fig 2.25

Pelvis Types Fig 2.24

Pelvic Floor Fig 2.24 and 2.25