[Music] so only about 70 or less of patients have tremor um a hundred percent of parkinson's patients have to have bradykinesia and they only have to have one other symptom it's also important to know that parkinson's syndrome itself has lots of non-motor features as well and we'll kind of get to those in a second so what is resting trimmer an asymmetric it's kind of moderate um amplitude frequency i mean it's predominantly when we say it's resting trimmer we mean literally the trimmer itself is present when the muscles involved are at rest although resting trimmer is the most cosmetic it is very important to understand and this is a hugely important piece for anybody considering functional neurosurgery it is hugely important to understand that actually out of all the motor symptoms of parkinson's resting trimmer is often the least disabling because it goes away with activity so resting tremor in parkinson's is not going to cause somebody to have shaking when they go to drink their water um it's often going to go away when that happens and so when we think about treatment again it's kind of going to focus on what are the actual symptomatology that's impacting quality of life the wrestling trimmer is always always going to worsen with stressors in order to check this you really want the hands or arms at rest so i often have them lay their hands in in their lap and we want to kind of really get them at rest you can get them provoke them or kind of have provocative questioning having them do serial sevens or kind of months of the year backwards something that's mentally challenging again because that's going to stress them it's going to actually help bring the trimmer out the location is commonly in the hands arms legs or jaw extra pyramidal rigidity so rigidity and even extrapyramidal is one of those words again it's like a buzzword that we use all the time but i think sometimes we don't really think about what we mean by it so rigidity is literally defined by abnormally increased resistance to movement that is independent of velocity of movement so it's increased tone against passive range of motion the reason i highlight this is that again as a neurosurgeon you're going to see lots of patients that have spasticity this is a different problem that also causes increased tone spasticity is a buzzword that we use to describe increased tone when it is related to an upper motor neuron injury like a corticospinal injury or a pyramidal tract injury as spasticity and the difference is that spasticity is speed dependent it causes this clasp knife phenomenon so the faster i try to move the leg when spasticity the more resistance i have and rigidity that is not going to be the case remember extra pyramidal means that this is an injury outside of the corticospinal tracts outside of the perimeter tracks and we know that this is an injury in the basal ganglia itself that's causing parkinson's rigidity and rigidity is independent of velocity so it doesn't matter how fast or slow i move the arm or leg the the tone is going to be the same and that is contrasted with spasticity parkinson's patients do not have spasticity they have rigidity multiple sclerosis stroke patients spinal cord injury patients they have spasticity because they have a corticospinal injury okay there's different qualities to the rigidity again cogwheel rigidity is this buzz term that i think is is kind of again a buzz term that's kind of probably over associated with parkinson's there's really no pathophysiologic difference between these two things lead pipe versus cogwheel the only difference with cognitive rigidity is it's when somebody has rigidity plus trimmer right so this is just normal rigidity plus trimmer the jerk that you feel the catch that you feel and pogo rigidity is really just the trimmer coming through itself so again these you can describe them using these terms these are descriptors these are not one is not more patho mnemonic for parkinson's versus the other both are suggestive of an extra criminal injury again that could be consistent with parkinson's and lastly postural instability this is our loss of confidence or what i like to say is our loss of our writing reflex not handwriting but uprightedness this is a feeling of imbalance and really this idea that we really kind of can't catch ourselves so another giant red flag that i would tell you as a person interested in neuroscience neurology or neurosurgery if your patient is telling you they are falling that is neurologic until proven otherwise the reason i say that's neurologic until proven otherwise is that it is so unnatural for somebody to fall most of the time if somebody is repeatedly falling to the ground they have some major issue neurologically to the point i often tell the students in my clinic that i could go up to you if you were standing in front of me and i could shove you and no matter how hard i shoved you odds are you wouldn't actually fall to the ground and the reason that you wouldn't follow the ground is we have lots and lots of neurologically driven built-in reflexes that keep us from falling to the ground and in parkinson's we lose that reflex we lose it and so these patients as soon as they get off balance they're on the ground before they even realize it how do we test this we stand we have them stand out of the chair with their arms crossed we have them walk and turn you can even do kind of a pullback test where i pull their shoulders back again and most people again no matter how hard i pulled you back you would just step back and catch yourself you wouldn't fall fall to the ground all right and the non-motor symptoms these describe the less physical features of parkinson's equally impactful in quality of life arguably at times more so and there's a laundry list of kind of non-motor features hey everyone ryan rad here from neurosurgerytraining.org if you like that video subscribe and donate to keep our content available for 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