GI anatomy Lecture: 2 د. عصام طارق Objectives: To define rectus sheath. To describe anatomy of inguinal canal. To relates types of inguinal hernia to the region. To explore spermatic cord.
Rectus Abdominis Rectus sheath Long fibrous sheath It contains: Lies close to midline Lower It encloses six RA & pyramidalis intercostal nerves It is formed by the 3 aponeuroses Sup. & inf. epigastric Vv. Pyramidalis
1- Above costal margin Costal margin 2- Between costal margin ASIS ASIS 3- Between ASIS & Symphysis Pubis
Between costal margin & ASIS I.O. Aponeurosis Splits to enclose RA Skin R.A. R.A. Below ASIS Skin Transversalis fascia R.A. R.A. Transversalis fascia All the 3 aponeuroses pass anterior to RA
Continuous above with diaphragmatic Fascia Fascia transversalis (opened) Arcuate line Inferior epigastric Vv. External iliac Vv. Iliacus Muscle Peritoneum Deep Inguinal Ring
Femoral sheath ASIS Downward protrusion of fascial lining of abd. wall Occupy med. part of the gap beneath Ing. Lig. Composed of 3 compartments Fascia transversalis Deep inguinal ring Spermatic cord Pubic tubercle Femoral Vv. in femoral sheath Inguinal ligament
Arcuate Line Inferior epigastric Vv. RA Deep ring Fascia transversalis Fascia iliaca Inguinal triangle External Iliac Vv. Femoral ring
Inguinal canal: Deep inguinal ring Fascia Transversalis Oblique canal Extends from deep to superficial ring Permits passage of spermatic cord Superficial inguinal ring
Roof: Arching lowest fibers of I.O. & T.A. Posterior wall Floor: Inguinal lig. Anterior wall
Shuttering Mechanisms of The Inguinal Canal
Viscera Linea Alba Peritoneum Fascia Transversalis Conjoint Tendon Int. Spermatic Fascia Reflected Part Trans Ab Internal Oblique Cremasteric muscle and Fascia External Oblique Apponeurosis Ext. Ob. Ext. Spermatic Fascia 1- Obliquity of The Canal 2- The Weak Walls Are Supported 3- Contraction of Conjoint Tendon 4- Contraction of Cremastric Muscle 5- Contraction of Inter crural Fibers
Spermatic cord Traverses inguinal canal from DIR to upper pole of testis Composed of: Vas & its art., testicular art. & lymphatics, pampiniform, Genitofemoral Nerve autonomic nerves, processus, cremasteric art & genital branch Covered Fascia with three Transversalis concentric layers of fascia Linea Alba Conjoint Tendon Int. Spermatic Fascia Reflected Part Trans Ab Internal Oblique Cremasteric muscle and Fascia External Oblique Apponeurosis Ext. Ob. Ext. Spermatic Fascia Ilioinguinal Nerve Femoral Branch of Genitofemoral Nerve
Hernia Hernia is protrusion of abdominal contents through a weak point in the abdominal wall
Types of Hernia I- Inguinal Hernia II- Femoral hernia a- Direct b- Indirect
Viscera Linea Alba Peritoneum Fascia Transversalis Conjoint Tendon Int. Spermatic Fascia Reflected Part Trans Ab Internal Oblique Cremasteric muscle and Fascia External Oblique Apponeurosis Ext. Ob. Ext. Spermatic Fascia Neck Hernial Sac Body Fundus
What is The Cause of Formation of a Hernial Peritoneal Sac?
We Need to Know a Quick Hint About The Development of The Testis In Order To Understand
External Oblique Apponeurosis Internal Oblique Transversus Abdominis Transversalis Fascia Peritoneum Superficial Inguinal Ring The Testis Vestige of Processus Vaginalis Peritoneum Processus Vaginalis Vestige of Processus Vaginalis Tunica Vaginalis Deep Inguinal Ring Testis Deep Inguinal Ring Superficial Inguinal Ring Tunica Vaginalis (Parietal Layer) Tunica Vaginalis (Visceral Layer)
Normal obliterated Processus Vaginalis Completely patent processus Vaginalis Indirect Inguinal Hernia
Features of Indirect Inguinal Hernia
4- Contents of Hernia is normally in front of the cord contents 1- The Neck is Usually Narrow 2- Neck is lateral to inferior epigastric Vv. 3- Body & fundus of hernial sac may be in canal or scrotum
Direct Inguinal Hernia
Rectus Abdominis Viscera Peritoneum Inferior Epigastric Vessel Linea Alba Fascia Transversalis Conjoint Tendon Reflected Part Internal Oblique Int. Spermatic Fascia Trans Ab External Oblique Apponeurosis Ext. Ob. Ext. Spermatic Fascia Cremasteric muscle and Fascia
Inguinal and Femoral Hernias (Comparison)
Ext. Oblique Linea Alba Superficial Inguinal Ring Conjoint Tendon Deep Inguinal Ring Direct Inguinal Spermatic Cord Hernia Fascia Transversalis Inguianal Hernia (Indirect) Femoral Hernia
Summary: Rectus sheath is formed by the aponeuroses of the three anterolateral muscles of the abdominal wall. Inguinal canal is an oblique passage in the lower part of the anterior abdominal wall that permits passage of spermatic cord to the testis. Hernia is protrusion of abdominal contents through a weak point in the abdominal wall