Lumbosacral Plexus Flashcards
Which branches of the lumbar plexus emerge lateral to psoas muscles?
Femoral
Iliohypogastric
Ilioinguinal
Lateral cutaneous nerve of the thigh
What are the roots of the obturator nerve?
L2, L3, L4
What are the roots of the femoral nerve?
L2, L3, L4
What are the roots of the iliohypogastric nerve?
L1
What are the roots of the ilioinguinal nerve?
L1
What are the roots of the lateral cutaneous nerve of the thigh?
L2, L3
Which 2 nerves make the sciatic nerve?
Tibial nerve
Common fibular nerve
What are the roots of the common fibular nerve?
L4, L5, S1, S2
What are the roots of the tibial nerve?
L4, L5, S1, S2, S3
Define a motor unit
A motor neuron and the skeletal muscle fibres it innervates
Define axial line
The junction of 2 dermatomes supplied from discontinuous spinal levels
Which branches of the lumbar plexus emerge medial to psoas muscles?
Obturator nerve
Lumbosacral trunk
What are the roots of the genitofemoral nerve?
L1, L2
What are the roots of the superior gluteal nerve?
L4, L5, S1
What are the roots of the inferior gluteal nerve?
L5, S1, S2
What are the roots of the posterior femoral cutaneous nerve?
S1, S2, S3
What are the roots of the pudendal nerve?
S2, S3, S4
What is the role of the iliohypogastric nerve?
Supplies sensation to the skin over the lateral gluteal region
Motor innervation to the abdominal muscles
Which spinal nerve roots contribute to the lumbar plexus?
L1 - L4
What is the role of the ilioinguinal nerve?
Innervates skin on upper middle thigh and genitalia
Innervate abdominal muscles
What is the role of the lateral cutaneous nerve of the thigh?
Innervate the skin of anterior, lateral thigh down to the knee
Which muscles does the femoral nerve innervate?
Iliacus, pectineus, sartorius and all of the quadriceps
Which parts of the skin does the femoral nerve innervate?
Anterior thigh
Medial leg
Which muscles are innervated by the superior gluteal nerve?
Gluteus minimus
Gluteus medius
Tensor fascia lata
Which muscles does the tibial portion of the sciatic nerve innervate?
Hamstrings (except short head of bicep femoris)
Hamstring part of adductor magnus
All the muscles in the sole of the foot
Which parts of the skin does the tibial nerve innervate?
Medial and posterior, lateral surface of foot
Sole
Which muscles does the common fibular nerve innervate?
Short head of biceps femoris
All muscles of anterior and lateral compartments of the leg
Extensor digitorum brevis
Which parts of the skin does the common fibular nerve innervate?
Anterior, lateral surface of leg
Dorsum of foot
What skin does the posterior femoral cutaneous nerve innervate?
Posterior surface of the thigh and the posterior surface of the leg
