Neuro Anatomy Flashcards
Where do the lateral and ventral corticospinal tracts decussate? What do they supply?
Lateral = medulla Ventral = ventral horn of cervical/thoracic spinal cord
Control of voluntary movement
Lateral = lower limbs
Ventral = upper limbs
What is the function of the extra-pyramidal tracts and what spinal pathways make up this system?
modulation and control of motor function
Rubrospinal Tectospinal Vestibulosinal Reticulospinal Corticobulbar
What is the function of the neurons in the dorsal columns?
proprioception and fine touch
What are the two dorsal columns called and what areas do they supply?
Cuneate = upper limbs Gracile = lower limbs
Where do the dorsal column axons decussate?
Medulla
What is the function of the neurons in the spinothalamic tract?
Pain, temperature and crude touch
Where do the spinothalamic axons decussate?
Within the spinal cord (ventral white comissure) roughly 2 spinal levels above entry
What clinical features would occur with a lesion to the spinothalamic tract on the R at the level of the brainstem?
loss of pain and temperature sensation in L upper and lower limbs
What clinical features would occur with a lesion to the spinothalamic tract on the R at the level of T4
Loss of pain and temperature in L lower limbs only
What clinical features would occur with a lesion to the dorsal columns on the R at the level of the Pons?
Loss of proprioception and fine touch in L upper and lower limbs
What clinical features would occur with a lesion to the dorsal columns on the R at the level of C1
Loss of proprioception and fine touch in R upper and lower limbs
What clinical features would occur with a lesion to the dorsal columns on the R at the level of T4
Loss of proprioception and fine touch in R lower limbs only
What clinical features would occur with a lesion to the corticospinal tracts on the R at a level before the pons?
Weakness of L lower and upper limbs
What clinical features would occur with a lesion to the corticospinal tracts on the R at the level of C1
Weakness of R lower and upper limbs
What clinical features would occur with a lesion to the corticospinal tracts on the R at the level of T4
Weakness of R lower limbs only
What are the motor and sensory functions of the median nerve?
Motor:
- Wrist flexion
- Finger flexion
- Pronation
- Thumb opposition and abduction weak pincer grip
- -> weak pincer grip and grip strength
Sensory:
- Thenar eminance
- Palmar aspect of lateral 3.5 fingers
What are the motor and sensory functions of the ulnar nerve?
Motor:
- Finger abduction and adduction
- little finger opposition
- -> weak hand
Sensory:
- Hypothenar eminence
- Palmar and dorsal aspects of medial 1.5 fingers
What are the motor and sensory functions of the radial nerve?
Motor:
- Elbow extension
- Wrist extension
- Finger extension
- -> wrist drop
Sensory:
- Lateral 2/3rds of dorsum of hand (1st web space)
What myotome is responsible for elbow flexion?
C5-C6
What myotome is responsible for elbow extension?
C7
What myotome is responsible for wrist flexion?
C7-C8
What myotome is responsible for wrist extension?
C7
What myotome is responsible for finger extension?
C8
What myotome is responsible for shoulder abduction?
C5
