GS - Videos of motor deficits Flashcards
What are the 3 different types of cerebellar lesions and what do they cause?
Cerebellar lesions - Cannot co-ordinate sensory and motor systems
Ataxia: Ataxia is a term for a group of disorders that affect co-ordination, balance and speech. Dysdiadochokinesia comes under this.
Dysmetria: Dysmetria is the inability to control the distance, speed, and range of motion necessary to perform smoothly coordinated movements.
Resting tremor: a person’s hands, arms, or legs may shake even when they are at rest. Also hyperkinesia comes under this (muscle spasm)
What would you expect to see in Parkinsons?
Hypokinesia/bradykinesia - seen in Parkinson’s - absence of spontaneous movements that usually animates a face. Patient will not blink much, lack head and mouth movements and doesn’t smile. Sems to not be moving and is like statue.
Parkinsons gait - stooped posture and short shuffling steps, short steps when turniing (pedestal turning), Not always but sometimes can see - extreme tremor in upper limbs
Parkinsonism resting tremor - regular frequency and amplitude of oscillations. As closes right hand tremor stops without activity thee tremor returns gaining amplitude with time. Looks like worried hands
Therefore, you should be absolutely clear that Parkinson’s disease is NOT associated with a generalized hyperkinesia.
What is Dysdiadochokinesia?
Dysdiadochokinesia - cerebellar disorder, cannot perform rapid alternating movements. Results from inability to co-ordinate antagonist muscle groups. Cannot rapidly pronate then supinate hands and cannot do rapid hand slapping
What would you see in an upper motor lesion?
Circumducting gait: This refers specifically to the outward swing of the leg when a patient is unable to bend their leg (in the case of this video clip, because the patient has suffered a stroke affecting the area of the left motor cortex that controls the right leg) - Patient cannot flex hip knee and ankle so swings leg laterally and rotates hips too side so leg can clear floor (think football fake kick swung around ball t take other way)
Hemiparesis: This is a partial paralysis or weakness of one side of the body. In the case shown in the video clip, it was caused by a stroke in the right cerebral hemisphere that has produced weakness of both the left arm and left leg. Muscles of the left side of the body also show spasticity (muscular stiffness caused by exaggerated muscular tone - A bit like a peg leg, Arm is also flexed when walking to confirm this
Increased Muscle Tone: This video clip shows not only the increase in resting muscle tone, but also the presence of enhanced stretch reflexes. Both result mainly from an increase in activation of alpha and gamma-motoneurones caused by an increase in the activity of brainstem motor systems (the vestibular nuclei and pontine reticular formation) which are no longer inhibited by collaterals of the corticospinal pathway (since fibres of this system have been damaged by the stroke).
Hoffman’s and Babinski’s signs: These are both examples of positive upper motoneurone signs. That is to say they are responses that are normally absent or masked and only become apparent after damage to the corticospinal pathway.
(Hoffmans flexion of thumb and first finger in response to mild stimulation of 2nd finger)
(Babinski - reversal of normal flexion reflex. Toes extend and flare)
What is Circumducting gait?
Circumducting gait: This refers specifically to the outward swing of the leg when a patient is unable to bend their leg (in the case of this video clip, because the patient has suffered a stroke affecting the area of the left motor cortex that controls the right leg) - Patient cannot flex hip knee and ankle so swings leg laterally and rotates hips too side so leg can clear floor (think football fake kick swung around ball t take other way)
Seen in UMN lesion
What is Hemiparesis?
Hemiparesis: This is a partial paralysis or weakness of one side of the body. In the case shown in the video clip, it was caused by a stroke in the right cerebral hemisphere that has produced weakness of both the left arm and left leg. Muscles of the left side of the body also show spasticity (muscular stiffness caused by exaggerated muscular tone - A bit like a peg leg, Arm is also flexed when walking to confirm this
Seen in UMN lesion
What is increased muscle tone?
Increased Muscle Tone: This video clip shows not only the increase in resting muscle tone, but also the presence of enhanced stretch reflexes. Both result mainly from an increase in activation of alpha and gamma-motoneurones caused by an increase in the activity of brainstem motor systems (the vestibular nuclei and pontine reticular formation) which are no longer inhibited by collaterals of the corticospinal pathway (since fibres of this system have been damaged by the stroke).
Seen in UMN lesion
What are Hoffman’s and Babinski’s signs?
Hoffman’s and Babinski’s signs: These are both examples of positive upper motoneurone signs. That is to say they are responses that are normally absent or masked and only become apparent after damage to the corticospinal pathway.
(Hoffmans flexion of thumb and first finger in response to mild stimulation of 2nd finger)
(Babinski - reversal of normal flexion reflex. Toes extend and flare)
Seen in UMN lesion
