Following are the features of coicospinal involvement except:
Correct Answer: Cog-wheel rigidity
Description: A i.e. Cog-Wheel rigidity - Involuntary movements (i.e. athetosis, ballism and chorea), tremor at rest and cogwheel (lead-pipe) rigidityQ are hyperkinetic whereas, akinesia, and bradykinesia are hypokinetic features of extrapyramidal system (EPS) like basal ganglia lesion or disease (eg Parkinson disease). Wing beating tremor or asterixis, dysahria, unsteady gait, and rigidity occur in hepato lenticular degeneration (Wilson's disease) involving putamen of lenticular nucleus.- Pyramidal (Coicospinal) tract lesion leads to increased muscle tone, spasticity (or clasp knife rigidity), clonus, exaggerated deep tendon reflexes and extensor plantar reflex (i.e. positive Babinski sign)Q.DifferenceFeatureUpper Motor Neuron(UMN /pyramidaltract) lesionLower MotorNeuron lesionMyopathyPyramindal systemExtrapyramidal system - It includes motor coex+ the axons descending- Denotes all those poion of thebrain and brain stem, that Muscle atrophy(wasting)NoneMarkedQMildthrough the pyramidaltract (PT) or coicocoribute to motor control andare not pa of the direct FascicultionNoneCommonQNonespinal tract.coicospinal pyramidalsystem. Distribution ofPyramidal or regionalDistal orProximal weakness segmental - Anterior coicospinal- Basal ganglia Muscle ToneIncreased (Spastic)QDecreased lost(flaccid)Normal/Decreased- Lateral coicospinal-Motor nuclei of reticularformation of brain stem ClonusPresentQAbsentAbsent - Vestibular nucleus Deep tendonExaggerated /hyperLostNomal or - Descending fibers which reflexes (jerks)activeQ/Hypoactivehypoactive convey the impulses fromthese nuclei to spinal cord. Babinski's signPresentQAbsentAbsent - Concerned with- Concerned with control of Plantar reflexExtensorQFlexorFlexorvoluntary activities ofbodyQposture, tone and equilibriumQ Superficialabdominal reflexLostLost only whenthe paicularneuronsupplying themuscle is lost.Normal Athetosis (i.e. continuous, slow writhing movemets) and chorea (rapid involuntary dancing movements) occur in an involuntary, disorganized way at the sta of voluntary movements. Ballism is involuntary flailing, intense, violent movements. Akinesia is difficulty in initiating movement & decreaed spontaneous unconscious movements such as swinging of arm during walking, different facial expressions related to emotional content of speech & thought and multiple gestures & fidgety actions that occur in all of us. Bradykinesia is slowness of movements.- Rigidity differs from spasticity because in it motor neuron discharge increases to both the agonist & antagonist muscles and so passive motion meets with a plastic, dead feeling continuous resistance that has been linked to bending a lead pipe & is therefore called lead pipe rigidity. Sometimes a series of "catches" (i.e. resistance f/b release f/b resistance) takes place during passive motion, then it is called cogwheel rigidity, but the sudden loss of resistance as seen in spastic extremity (i.e. clasp knife rigidity) is absent in EPS lesions. Resting tremors d/t regular alternating 8 Hz contractions of antagonistmuscles, disappears with activity.
Category:
Physiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now