Anatomy: ABD Wall and Pevis

Camper's Fascia

The superficial fatty layer of subcutaneous tissue located on the anterolateral abdominal wall.

Scarpa's Fascia

The deeper membranous layer of subcutaneous tissue of the anterolateral abdominal wall located below the umbilicus, which is continuous with the fascia lata of the thigh and fundiform ligament of the penis.

External Oblique Muscle

The most superficial flat muscle of the anterolateral abdominal wall, innervated by thoraco-abdominal nerves (T7–T11) and the subcostal nerve, which functions to compress abdominal contents as well as flex and rotate the trunk.

Internal Oblique Muscle

The intermediate flat muscle layer of the anterolateral abdominal wall whose fibers run deep to the external oblique and combine with the transversus abdominis aponeurosis to form the conjoint tendon.

Transversus Abdominis Muscle

The deepest flat muscle layer of the anterolateral abdominal wall whose fibers run horizontally to compress and support the abdominal viscera.

Rectus Abdominis Muscle

A long vertical muscle extending from the pubic symphysis and pubic crest to the xiphoid process and costal cartilages 5–7, functioning to flex the trunk and compress abdominal viscera.

Linea Alba

A dense fibrous midline band extending from the xiphoid process to the pubic symphysis, formed by the interlacing aponeurotic fibers of the flat abdominal muscles.

Linea Semilunaris

A curved linear impression along the lateral margin of the rectus abdominis muscle marking the junction where the flat muscle bellies transition into their aponeuroses.

Rectus Sheath

A multi-layered aponeurotic envelope enclosing the rectus abdominis muscle, formed by variable contributions from the external oblique, internal oblique, and transversus abdominis aponeuroses depending on the thoracic, umbilical, or pubic level.

Arcuate Line

An anatomical transition line on the posterior wall of the rectus sheath located inferior to the umbilicus, below which all aponeurotic layers shift anterior to the rectus abdominis muscle.

Transversalis Fascia

A continuous sheet of deep fascia lining the internal surface of the transversus abdominis muscle, situated directly posterior to the rectus abdominis muscle below the level of the arcuate line.

Inguinal Ligament

The dense, inferior folded margin of the external oblique aponeurosis spanning from the anterior superior iliac spine (ASIS) to the pubic tubercle.

Conjoint Tendon (Inguinal Falx)

The common insertion formed by the fused aponeuroses of the internal oblique and transversus abdominis muscles into the pubic crest and pectineal line.

Inguinal Canal

An oblique passageway (~3–5 cm long) through the lower anterolateral abdominal wall extending from the deep inguinal ring to the superficial inguinal ring, transmitting the spermatic cord or round ligament of the uterus.

Deep Inguinal Ring

An entrance opening formed by an evagination of the transversalis fascia located lateral to the inferior epigastric vessels.

Superficial Inguinal Ring

A triangular exit opening in the external oblique aponeurosis situated superolateral to the pubic tubercle.

Inguinal (Hesselbach) Triangle

An anatomical space on the deep anterior abdominal wall bounded inferiorly by the inguinal ligament, medially by the lateral border of the rectus abdominis muscle, and laterally by the inferior epigastric vessels.

Direct Inguinal Hernia

An acquired hernia in which abdominal viscera protrude directly forward through a weakness in the posterior wall of the inguinal triangle, medial to the inferior epigastric vessels.

Indirect Inguinal Hernia

A congenital or acquired hernia in which abdominal contents enter the deep inguinal ring lateral to the inferior epigastric vessels and traverse the entire length of the inguinal canal.

External Spermatic Fascia

The outermost fascia wrapping the spermatic cord and testis, derived directly from the aponeurosis of the external abdominal oblique muscle.

Cremasteric Muscle and Fascia

The middle covering layer of the spermatic cord derived from the internal abdominal oblique muscle and its fascia, responsible for elevating the testis.

Internal Spermatic Fascia

The innermost fascial sheath surrounding the spermatic cord, derived directly from the evaginated transversalis fascia.

Tunica Vaginalis

A double-layered serous sac surrounding the testis derived from the embryonic processus vaginalis, consisting of outer parietal and inner visceral layers.

Pampiniform Plexus

A network of venous vessels surrounding the testicular artery within the spermatic cord that aids in thermoregulation of the testis.

Hydrocele

An abnormal accumulation of excess serous fluid within the tunica vaginalis sac or along a persistent processus vaginalis.

Varicocele

An abnormal dilation and elongation of the pampiniform plexus of veins in the scrotum, characteristically feeling like a "bag of worms" on palpation.

Cremasteric Reflex

A neurological reflex elicited by stroking the skin of the superomedial thigh (stimulating the ilioinguinal nerve) to evoke contraction of the cremaster muscle and elevation of the ipsilateral testis.

Vasectomy

A surgical procedure for male sterilization involving bilateral ligation and transection of the ductus deferens through the scrotal wall