Lumbar plexus (dave's notes) Flashcards
From what does the lumbar plexus arise and via what route?
The anterior rami of the upper four lumbar vertebrae segmentally supply quadratus lumborum and psoas, then form a plexus
What does the lumbar plexus supply?
Primarily concerned with supplying skin and muscle “borrowed from the trunk”??? but also anterior abdominal wall. Also makes significant contributions to the sacral plexus.
What is the nerve root that iliohypogastric and ilioinguinal arise from?
L1
Which aspect of psoas do iliohypogastric and ilioinguinal nerves arise from?
Lateral
Describe the iliohypogastric and ilioinguinal nerves
Really part of the first lumbar segmental body-wall nerve and its collateral
What do the iliohypogastric and ilioinguinal nerves supply?
skin over the inguinal region, the front of the scrotum, internal oblique muscle and transversus abdominus muscle
What is the nerve root that the genitofemoral nerve arises from?
L1,2
Which aspect of psoas does the genitofemoral nerve arise from?
Anterior
Describe the genitofemoral nerve and what it supplies
L1 is the femoral part, supplying the skin below the middle of the inguinal ligament. L2 is the genital part supplying the tunica vaginalis, spermatic fascia and cremaster muscle
List the nerves of the lumbar plexus
Iiliohypogastric and ilioinguinal Genitofemoral Lateral femoral cutaneous Femoral Obturator
From what nerve roots does the lateral femoral cutaneous nerve arise?
L2, 3, (posterior divisions)
From what aspect of psoas does the lateral femoral cutaneous nerve arise?
Lateral
What does the lateral femoral cutaneous nerve supply?
It is wholly sensory to the iliac fascia and peritoneum of the iliac fossa and the lateral side of the thigh down to the knee
From what nerve roots does the femoral nerve arise?
L2,3,4 (posterior divisions)
From what aspect of psoas does the femoral nerve arise?
Lateral
Briefly describe the course of the femoral nerve
It crosses between psoas and iliacus, where it divides into 9-10 branches; superior and deep
From what nerve roots does the obturator nerve arise?
L2,3,4
From what aspect of psoas does the obturator nerve arise?
Medially
Describe the course of the obturator nerve
The obturator nerve lies on the ala of the sacrum slanting down on the side wall of the pelvis, and from the angle of the internal iliac artery and external iliac artery it runs to the obturator foramen splitting anteriorly and posteriorly
List the superficial branches of the femoral nerve and what they supply
Nerve to pectineus - to the muscle
Nerve to sartorius - to the muscle and then continues on as the intermediate femoral cutaneous nerve
Intermediate femoral cutaneous nerve - pierces sartorius and supplies skin and fascia kata over the front of the thigh
Medial femoral - supplies the medial side of the thigh plus knee
List the deep branches of the femoral nerve and what they supply
Nerve to rectus femoris - usually x2 and also supplies hip joint
Nerve to vastus lateralis
Nerve to vastus intermedius
Nerve to vastus medialis
Saphenous nerve gradually crosses the femoral artery, gives branches, then supplies skin and periosteum over the tibia
Describe the course of the anterior and posterior divisions of the obturator nerve, and what each supplies.
The posterior division supplies obturator externus, piercing the upper border then running deep to adductor brevis. A slender branch supplies the knee joint
The anterior division passes over obturator externus and emerging into the thigh supplies the hip joint, adductor brevis and longs and may help to supply pectineus
