Abdomen: Inguinal Region Flashcards
Inguinal region
- Area between ASIS and pubic tubercle
- Structures enter/exit abdominal cavity to/from
lower extremity
Scrotum/labia majora
Clinical: site of inguinal hernias
Structures of inguinal region enter/exit abdominal cavity to/from
- Lower extremity
- Scrotum/labia majora
Clinical importance of inguinal region
- Site of inguinal hernias
Inguinal canal
- Oblique passageway through inferior abdominal wall
- Narrower in females
Inguinal canal is formed by
- Layers of abdominal wall
- Parallels inguinal ligament
Inguinal canal is the pathway for
- Structures to pass from abdomen to external genitalia
Inguinal canal in males transmits
- Spermatic cord with all of its content
- Ilioinguinal nerve (males and females)
- Genital branch of genitofemoral nerve (males and females)
Inguinal canal in females transmits
- Round ligament (females)
- Ilioinguinal nerve (males and females)
- Genital branch of genitofemoral nerve (males and females)
Inguinal canal is strengthened by
- Oblique orientation
- Abdominal wall muscle contraction
- Aponeuroses and fascias
Posterior boundary of inguinal canal
- Transversalis fascia
- Conjoint tendon (falx inguinalis)
Conjoint tendon (falx inguinalis)
- Combined aponeurosis of TA and IO
Conjoint tendon (falx inguinalis) inserts onto
- Pubic crest
- Pectineal line (pecten pubis)
Anterior boundary of inguinal canal
- EO aponeurosis & IO muscle
Roof of inguinal canal
- TA and IO
- Transversalis fascia
- Medial crus
Floor of inguinal canal
- Lateral crus
- Inguinal ligament
- Lacunar ligament
2 openings of inguinal canal
- Deep inguinal ring
- Superficial inguinal ring
Deep inguinal ring is created by
- Created by invagination of transversalis fascia
Deep inguinal ring is located
- Lateral to inferior epigastrics
- Above midpoint of inguinal ligament
Superficial inguinal ring
- Opening located ~ 1cm superolateral to pubic tubercle
Superficial inguinal ring is created by
- External oblique aponeurosis
Superficial inguinal ring is formed by
- Medial and lateral crura
- Intercrural fibers
Derivatives of EO aponeurosis
- Inguinal ligament (Pouparts ligament)
- Superficial inguinal ring
- Lacunar ligament (Gimbernat)
- Pectineal ligament (Cooper)
- Reflected inguinal ligament
Inguinal ligament (Pouparts ligament)
- Inferior reflection of EO aponeurosis
Inguinal ligament (Pouparts ligament) attaches to
- ASIS to pubic tubercle
Superficial inguinal ring is formed by
- Medial crus
- Lateral crus
Medial crus (of superficial inguinal ring) attaches to
- Pubic symphysis
Lateral crus (of superficial inguinal ring) attaches to
- Pubic tubercle
Lacunar ligament (Gimbernat) attaches to
- Superior pubic ramus
Pectineal ligament (Cooper) runs along
- Pectineal line of pubis (pecten pubis)
Testes develop in
- Upper lumbar region
Gubernaculum
- Fibrous cord
- Attaches testes/ovaries to anterolateral abdominal wall
Gubernaculum is involved in
- Gonadal descent
Gubernaculum degenerates, and remnant becomes
- Posterior scrotal ligament (M)
- Ovarian & round ligaments (F)
Process vaginalis
- Diverticulum of the peritoneum
Process vaginalis outpouches and
- Carries abdominal wall layers with it
Process vaginalis degenerates except for
- Distal portion (tunica vaginalis)
Testes descend into scrotum and become
- Ensheathed by abdominal wall layers
* Except for transversus abdominis*
Cryptorchidism
- Undescended testicle
Scrotum
- Outpouching of lower abdominal wall
- Thin, pigmented skin
Content of scrotum
- Testicles
- Epididymis
- Spermatic cord
Layers of the scrotum
- Skin
- Dartos fascia/muscle (superficial fascia)
- External spermatic fascia
- Cremaster fascia/muscle
- Internal spermatic fascia
- Tunica vaginalis parietal layer
- Tunica vaginalis visceral layer
Dartos fascia/muscle (superficial fascia) contains
- Fat free superficial fascia (contains smooth muscle)
- Continuous abdominal superficial fascia
- Dartos muscle
Dartos muscle
- Thermoregulation (autonomically innervated)
External spermatic fascia is derived from
- EO aponeurosis
Cremaster fascia/muscle is derived from
- IO aponeurosis
Internal spermatic fascia is derived from
- Transversalis fascia
Tunica vaginalis parietal layer is derived from
- Process vaginalis
Tunica vaginalis visceral layer is derived from
- Process vaginalis
Testes
- Male reproductive organ
- Suspended by spermatic cord
- Consists of lobules of seminiferous tubules
Testes are involved with
- Production of spermatozoa and testosterone
Tunica albuginea
- Fibrous covering of the testes
Pathway of testes
- Seminiferous tubules > straight tubules > rete teste (MT) > efferent ductules > epididymis
Epididymis
- Storage and maturation of sperm
- Highly convoluted and densely packed tube
Epididymis consists of
- Head
- Body
- Tail: connected to vas deferens
Tunica vaginalis
- Closed off distal part of process vaginalis (outpouching of peritoneum)
- Visceral and parietal layer
Visceral layer of tunica vaginalis
- Covers testis, epididymis
Parietal layer of tunica vaginalis
- Lines internal spermatic fascia & distal spermatic cord
Cavity of tunica vaginalis
- Between parietal and visceral layers
- Small amounts of fluid
Spermatic cord
- Contains structures going to and from testis
- Passes into the scrotum
Vas deferens
- Connects epididymis to ejaculatory duct
Testicular artery
- Arises from abdominal aorta
- Supplies testis and epididymis
Artery to vas deferens
- Arises from inferior vesicular artery
Cremasteric artery
- Arises from inferior epigastric artery
Pampiniform venous plexus
- Network of veins
- Converge to form testicular vein
Lymph vessels
- Drain into lumbar lymph nodes
Sympathetic nerves
- Travel with testicular artery and ductus deferens
Genital branch of genitofemoral nerve
- Supplies cremaster muscles
3 fascial layers of spermatic cord
- Internal spermatic fascia
- Cremasteric muscle and fascia
- External spermatic fascia
Ilioinguinal nerve is NOT a content of the spermatic cord, but a content of the
- Inguinal canal
Ilioinguinal nerve doesn’t pass through deep ring, but does exit the
- Superficial ring
Testicular arteries (paired) pathway
- Branch from abdominal aorta
- Cross ureter
- Enter deep inguinal ring and pass through inguinal canal
Pampiniform plexus
- Network of veins (8-12)
- Surround testicular artery in spermatic cord
- Converge to form testicular veins
Function of pampiniform plexus surrounding testicular artery in spermatic cord
- Thermoregulation
- Cools arterial blood
Right testicular vein drains to
- IVC
Left testicular vein drains to
- Left renal vein
Lymphatic drainage of testes
- Lumbar nodes (paraaortic)
Lymphatic drainage of scrotum
- Superficial inguinal nodes
Hydrocele
- Accumulation of fluid in the cavity of tunica vaginalis
Hydrocele is commonly caused by
- Patent process vaginalis
- Transilluminates
Testicular hematocele
- Accumulation of blood in cavity of TV
Varicocele
- Varicose veins of the pampiniform plexus
- “bag of worms”
Varicocele cause
- Defective venous valves or venous problem
- Left more common than right
- Can cause fertility problems
- Do not transilluminate
Inguinal Hernia
- Abnormal protrusion of abdominal content
from area where it normally resides - M >F
Indirect Inguinal Hernia
- Usually the result of a patent process vaginalis
- Most common inguinal hernia
Indirect Inguinal Hernia enters
- Deep ring, lateral to inferior epigastric vessels
- Can exit superficial ring and pass into scrotum
Direct Inguinal Hernia occurs in
- Inguinal triangle
Direct Inguinal Hernia enters
- Medial to inferior epigastric a.
- Can exit through superficial ring
- Rarely enters scrotum
Inguinal Triangle Boundaries
- Medial: rectus abdominis
- Lateral: inferior epigastric vessels
- Inferior: inguinal ligament
Inguinal triangle medial boundary
- Rectus abdominis
Inguinal triangle lateral boundary
- Inferior epigastric vessels
Inguinal triangle inferior boundary
- Inguinal ligament
Femoral Hernia
- Passes through femoral ring and canal
- Posterior-inferior to inguinal ligament
- F>M because of wider bone structure
The necks of inguinal hernias are
- Superomedial to pubic tubercle
The necks of femoral hernias are
- Inferolateral to pubic tubercle