Sciatica and Femoral Hernia Flashcards
How many spinal nerve pairs are there, and are they sensory, motor or mixed?
- 31
- Mixed
Boundaries of intervertebral foramen
- Anterior = IVD + back of vertebral bodies
- Superior = pedicle
- Inferior = pedicle
- Posterior = capsule of facet joint + ligamentum flavum
What type of joint occurs between vertebral bodies and IVDs?
Secondary cartilaginous
What are the superior and inferior surfaces of IVDs lined with?
Hyaline cartilage
Function of nucleus pulposus
Shock absorber –> distribute forces in radial fashion
What is the annulus fibrosus made of?
15-25 sheets of tightly packed alternating directing collagen lamellae
Where do cervical spinal roots exit, and what is the exception and why?
- Normally above corresponding pedicle
- C8 passed above T1 –> no corresponding pedicle
Where do thoracic spinal roots exit?
Below corresponding pedicle
Where do lumbar spinal roots exit?
Below corresponding pedicle
What are spinal nerve plexuses formed by?
Ventral rami of corresponding nerve roots
Nerve root values of cervical plexus
C1-5
Nerve root values of brachial plexus
C5-T1
Nerve root values of lumbar plexus
T12-L4
Nerve root values of lumbosacral trunk
L4-5
Nerve root values of sacral plexus
L4-S4
Divisions of sciatic nerve
- Common peroneal nerve
- Tibial nerve
Where does the sciatic nerve pass in the posterior thigh?
Beneath long head of biceps femoris
Types of IVD herniation
- Central
- Posterolateral
- Far lateral
What is sciatica, and what causes it?
- Pain radiating down lower limb with(out) back pain
- Disc herniation (L4/5 or L5/S1)
Which nerve roots are commonly compressed in sciatica?
L5 + S1
What sensory loss occurs with S1 root compression?
Lateral foot + posterior lateral leg
Treatment of sciatica
- Pain management
- Physiotherapy (extension, lower back + sciatic nerve exercises)
- Surgical decompression
Where does an inguinal hernia occur?
Superomedial to pubic tubercle
Where does a femoral hernia occur?
Inferolateral to pubic tubercle
What is a reducible hernia?
Contents may return spontaneously or pushed back by gentle pressure
What is an incarcerated hernia?
Irreducible, possibly presenting with bowel obstruction (don’t try to reduce forcefully)
What is a strangulated hernia?
Blood supply is threatened (requires emergent surgical intervention to precent necrosis of contents)
Boundaries of femoral triangle
- Sartorius (lateral)
- Inguinal ligament (superior)
- Adductor longus (medial)
Boundaries of femoral ring
- Inguinal ligament (anterior)
- Iliopectineal ligament, pubic bone + fascia over pectineus (posterior)
- Edge of lacunar ligament (medial)
- Thin septum (lateral)
