Bony Landmarks of the Abdomen Gross Anatomy Rib 7

of the Rib 10 Xiphoid process

Costal margin L1 ANTEROLATERAL Rib 10 Arcuate line Iliac crest ABDOMINAL WALL L5 Anterior superior iliac spine (ASIS) M1 Gross and Developmental Anatomy 8:00 AM, November 11, 2008 Sacral promontory Pubic tubercle Dr. Milton M. Sholley Pectineal line Professor of Anatomy and Neurobiology 2 Pubic symphysis

Soft tissues fill the bony gap and form the Soft Tissue Landmarks Anterolateral Abdominal Wall on the Anterolateral Abdominal Wall

Examples of soft tissues Linea alba (midline interdigitation Skin of aponeuroses) Superficial fascia Linea semilunaris (lateral rectus plane) Umbilicus Muscle (at vertebral level Aponeurosis L4 in non-obese persons) Inguinal ligament (attached at ASIS and pubic tubercle)

3 4

Quadrants subdivide the anterolateral abdominal wall and allow more precise localization of clinical findings.

Midline

Upper right Upper left quadrant quadrant Transumbilical line crosses umbilicus (if not obese) and vertebral body L4 Lower right Lower left quadrant quadrant

5 6 Nine Regions Langer’s lines - Cleavage lines of the skin may be used to subdivide the anterolateral abdominal wall, to make the localization of clinical findings even more precise.

Mid-clavicular lines

E Transpyloric line U Intertubercular line

H Nine regions right hypochondriac epigastric left hypochondriac right lumbar umbilical left lumbar right inguinal hypogastric left inguinal 7 8

The superficial fascia of the anterolateral abdominal wall has Two Layers - Camper’s and Scarpa’s. Nerves and Dermatomes T10 crosses the umbilicus

Skin T7 T7 Camper’s layer T8 T8 (the fat-containing T9 T9 superficial layer of the superficial fascia) T10 T10 Scarpa’s layer T11 T11 (the membranous layer T12 T12 of the superficial fascia - L1 lies on the deep surface L1 of the fatty layer)

9 10

Superior epigastric artery

Inferior epigastric artery 11 12 Cutaneous Lymphatic Drainage Superficial Inguinal Lymph Nodes The watershed crosses the umbilicus

13 14

External and Internal Transversus Abdominis Muscle Abdominal Oblique Muscles lies deep to the internal oblique

External oblique Internal oblique Internal oblique Transversus abdominis muscle muscle muscle muscle (ply 1) (ply 2) (ply 3) (ply 2) aponeurosis aponeurosis aponeurosis aponeurosis

Inguinal ligament

15 16

Rectus Abdominis Muscle Rectus Sheath Formation is enclosed in the Rectus Sheath superior (A) and inferior (B) to the arcuate line

Skin Linea alba Anterior layer Superficial of rectus sheath fascia Posterior layer

1 2 3

Rectus Transversalis abdominis 1. Aponeurosis of external fascia oblique muscle muscle Extraperitoneal Posterior layers Posterior layer fat Anterior layer of rectus sheath A 2. Aponeurosis of internal Peritoneum of rectus sheaths oblique muscle of rectus sheath

Arcuate line 3. Aponeurosis of transversus B abdominis muscle Arcuate line Linea alba Anterior layer Transversalis of rectus sheath fascia Transversalis Tendinous fascia 1 2 intersection 3

Transversalis fascia Peritoneum 17 Extraperitoneal 18 fat Peritoneum 19 20

Inguinal ligament

Spermatic cord

21