11. Spleen Flashcards
functions mainly as a blood filter, removing old red blood cells. It also plays a role in both cell-mediated and humoral immune responses.
spleen
the spleen is located in the
upper left quadrant of the abdomen, under cover of the diaphragm and the ribcage
Spleen – is an intraperitoneal organ, entirely surrounded by peritoneum except at the
splenic hilum
The spleen is connected to the stomach and kidney by parts of the
greater omentum – a double fold of peritoneum that originates from the stomach
•Gastrosplenic ligament
•Splenorenal ligament
anterior to the splenic hilum, connects the spleen to the greater curvature of the stomach.
gastrosplenc ligament
posterior to the splenic hilum, connects the hilum of the spleen to the left kidney. The splenic vessels and tail of the pancreas lie within this ligament
Splenorenal ligament
between Splenorenal ligament
and Gastrosplenic ligament
is the
lesser sac
outer surface of the spleen can be anatomically divided into
- Diaphragmatic surface
* Visceral surface
this surface of the spleen is smooth
posteromedial and ifneiror borders
this surface of the spleen contain notches
anterior and superior borders
enlargement of the spleen (known as splenomegaly) the ______moves inferomedially, and its notches can be palpated.
superior border
posterior to the splen are the ribs
9-11
The spleen is a highly vascular organ. It receives most of its arterial supply from the
splenic artery
splenic artery arises from
celiac trunk
splenic artery. – this vessel arises from the coeliac trunk, running laterally along the superior aspect of the pancreas, within this structure
splenorenal ligament
removal of one of the segments of the spleen without affecting the others
subtotal splenectomy
Venous drainage occurs through the splenic vein. It combines with the superior mesenteric vein to form the
hepatic portal vein
nerve supply of the spleen comes from
celiac plexus
The lymphatic vessels of the spleen follow the splenic vessels mentioned above and drain into the
pancreaticosplenic lymph nodes
abdominal organ with the highest incidence of injury.
spleen
A splenic rupture occurs when there is a break in its
fibroelastic capsule - disrupting the underlying parenchyma.
splenic rupture is often associated with
left rib fractures -bony fragment easily tearing the capsule.
The liver and bone marrow take over some of the functions of the spleen, however, an individual who has no spleen are at risk to
bacterial infections and – requires life long antibiotics.
Indications for splenectomy
- injury to the spleen and subsequent haemorrhage are life threatening
- haemolytic anaemia, idiopathic thrombocytopenic purpura, thrombotic thrombocytopenic purpura, hypersplenism and prolieferative disorders such as myelofibrosis of lymphoma.
this ligament carries the short gastric, left gastroepiploic vessels
gastrosplenic ligament
this ligament carries the splenic vessels
splenicorenal ligament
thick, fusiform, muscles of the loin
psoas major
large, triangular on the lateral side of the psoas major
iliacus
quadrilateral muscles
quadratus lumborum
lumbar plexus is formed within this muscle
Psoas major muscle
lumbar plexus formed by ventral rami of
L1-L4
also receives contributins from T12
branches of the lumbar plexus emerge from ___ of the psoas
lateral and medial borders
anterior surface
network of nerve fibres that supplies the skin and musculature of the lower limb.
lumbar plexus
lumbar pelxus is anterior to this structure
anterior to the transverse processes of the lumbar vertebrae.
The spinal nerves L1 – L4 form the basis of the lumbar plexus. At each vertebral level, paired spinal nerves leave the spinal cord via the
intervertebral foramina of the vertebral column
branches of the lumbar plexus
- Iliohypogastric Nerve
- Ilioinguinal Nerve
- Genitofemoral Nerve
- Lateral Cutaneous Nerve of the Thigh
- Obturator Nerve
- Femoral Nerve
I, I Get Leftovers On Fridays.
first major branch of the lumbar plexus
iliohypogastric nerve
iliohypogastric nerve perforates this muscle
transversus abdominis
roots of Iliohypogastric Nerve
L1 (with contributions from T12)
This nerve runs to the iliac crest, across the quadratus lumborum muscle of the posterior abdominal wall. It then perforates the transversus abdominis, and divides into its terminal branches.
iliohypogastric nerve
motor and sensory fx of iliohypogastric nerve
Motor Functions: Innervates the internal oblique and transversus abdominis.
Sensory Functions: Innervates the posterolateral gluteal skin in the pubic region
After innervating the muscles of the anterior abdominal wall, it passes through the superficial inguinal ring to innervate the skin of the genitalia and middle thigh.
Ilioinguinal Nerve
root of Ilioinguinal Nerve
L1
root of Genitofemoral Nerve
L1,L2
root of Lateral Cutaneous Nerve of the Thigh
L2,L3
root of Obturator Nerve
L2,3,4
root of femoral nerve
L2,3,4
motor fx of ilioinguinal nerve
Innervates the internal oblique and transversus abdominis.
sensory fx of ilioinguinal nerve
- Innervates the skin on the superior antero-medial thigh.
- males, it also supplies the skin over the root of the penis and anterior scrotum.
- females, it supplies the skin over mons pubis and labia majora.
After leaving the psoas major muscle, the genitofemoral nerve quickly divides into
- genital branch
* femoral branch
motor fx of genitofemoral nerve
The genital branch innervates the cremasteric muscle.
sensory fx of genitofemoral nerve
- genital branch innervates the skin of the anterior scrotum (in males) or the skin over mons pubis and labia majora (in females).
- femoral branch innervates the skin on the upper anterior thigh.
This nerve has a purely sensory function.
It enters the thigh at the lateral aspect of the inguinal ligament, where it provides cutaneous innervation to the skin there.
Lateral Cutaneous Nerve of the Thigh
sensory fx of Lateral Cutaneous Nerve of the Thigh
Innervates the anterior and lateral thigh down to the level of the knee.
motor fx of obturator nerve
Innervates the muscles of the medial thigh – the obturator externus, adductor longus, adductor brevis, adductor magnus and gracilis.
sensory fx of Obturator nerve
Innervates the skin over the medial thigh.
motor fx
Femoral Nerve
Innervates the muscles of the anterior thigh – the illiacus, pectineus, sartorius and quadriceps femoris.
sensory fx
femoral nerve
Innervates the skin on the anterior thigh and the medial leg.