Motor Systems: Disorders

Question 1

Muscular dystrophy

Answer 1

x-linked gene - codes for dystrophin protein. faulty regulation of Ca stores, consequently contractile properties of muscles are abnormal

Question 2

myasthenia gravis

Answer 2

immune malfunction - produce antibodies that attack own acetylcholine receptors. characterized by rapid fatigue after normal start of movements, treatable with immune suppressants

Question 3

spinal cord injury

Answer 3

transection with extensive damage - leads to flaccid paralysis. with less damage, some reflexes persist

Question 4

flaccid paralysis

Answer 4

complete loss of movement including reflexes below level of break

Question 5

brown sequard syndrome

Answer 5

hemitransection of cord, motor tracts cross in brain but sensory fibres cross in the spinal cord

Question 6

cortical damage

Answer 6

lesions of motor areas due to stroke, tumour, etc. causes paresis or sometimes plegia, usual accompanied by spasticity due to loss of inhibition from brain on ventral horn motor neurons

Question 7

baninski’s sign

Answer 7

upgoing toe when sole is stroked

Question 8

epilepsy

Answer 8

if in a motor area, can produce jacksonian march. area of seizure spreads to adjacent areas, tonic-clonic movements appear more and more in body

Question 9

basil ganglia problems

Answer 9

parkinsons disease, huntingtons disease, and hemiballismus

Question 10

parkinsons disease

Answer 10

loss of dopamine containing projection from the substantia nigra to teh striatum. tremor, flat effect, trouble initiating movements, shuffling gait, dementia. treatable for a while by replacing lost dopamine with L-DOPA or transplants

Question 11

huntingtons disease

Answer 11

genetic deterioration of the lenticular nucleus. gives rise to writhing choreiform movements, dementia. no treatment

Question 12

hemiballismus

Answer 12

violent uncontrollable flinging of limbs due to leason of subthalamic nucleus. may cause death through exhaustion