A few notes on selected topics that I’ve collected on Neurology. All are basics and tips that makes studying the subject much easier (IMO).

TIPS
• Cranial nerves 1, 2, 8 are purely sensory
• Area 8; voluntary conjugate eye movement. Lesion: saccadic (jerky) reading
• Types of conjugate eye movement; Voluntary (area 8 ) & reflex (areas 18, 19)
• Association sensory areas are in dominant hemispheres only
• Facial & hypoglossal nuclei have only contralateral motor supply; other cranial nuclei have 2 (contra. & ipsi.)

PATHWAYS
• Pyramidal tract; corticobulbar (area 4, 6 » brainstem nucleai) & corticospinal (area 4, 6 » AHCs in ventral horn of spinal cord)
• Pain/Temp.; lateral spinothalamic tract of lateral lemniscus then to C.C. – situated laterally in the spinal cord
• Crude touch; anterior spinothalamic tract of lateral lemniscus then to C.C. – situated anteriorly
• Fine touch/Deep sens.; medial lemniscus then to C.C. – situated posteriorly
P.S. in the 3 sensory pathways;
1st order neuron is Post. RG
3rd order neuron is Thalamus
Fibers cross to the opp. side after the 2nd order neurone
In deep sens. pathway, the fibers cross to the opp. side in the medulla (G & C nuclei), not in the spinal cord. That’s why there’s IPSI. deep sens. loss in spinal hemiplegia, not contra.

Cauda Equina; collection of spinal roots, begins at the L1-L2 vertebral junction.

HEMIPLEGIA
• Shock stage (flaccid paralysis) » Spasticity stage
• Spasticity is clasp-knife; could be cog-wheel or lead-pipe if there’s assoc. extrapyramidal lesion
• Spaticity is more in flexors (UL) and in extensors (LL)
• Exag. deep reflexes (incl. +ve Babiniski) & lost superficial reflexes
• Gait; if uni (circumduction), bi (scissors)
• Spinal cord hemiplegia
AT level of lesion
ipsi motor
ipsi senosry (all)
BELOW level of lesion
ipsi motor
ipsi deep sens.
contra pain/temp
both crude touch

In PARAPLEGIA, sensory loss differs and there’s usually sphincteric manifestations.
SENSORY
¤ Extramedullary (band-tightening)
• all sens. diminished
• early loss of saddle area sens (S3,4,5) as they’re the outermost fibers
¤ Intramedullary
• sensory loss of pain/temp. d.t. crossing AT level of lesion only (jacket sensory loss)
• touch/deep sens. intact as they’re most superficial (dissociative sensory loss)
• sacral spare
SPHINCTERIC MANIFESTATIONS (UMNL)
• after a bilateral lesion only
• acute; retension » precipitancy
• gradual; partial (precipitancy), complete ‘regular’ evac. (AUTOMATIC bladder)

NEUROGENIC BLADDER (S2,3,4)
¤ lesion AT level of reflex arc (LMNL)
• sensory fibers (G/C of S2,3,4) » sensory atonic bladder
• motor fibers (AHCs of S2,3,4) » motor atonic bladder (emerg.)
• both » AUTONOMIC (totally ‘irregular’)
¤ lesion ABOVE (UMNL)