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Movement signs and symptoms of Parkinson's disease

Video transcript

so just before we jump into the movement-related signs and symptoms of Parkinson's disease let's just remind ourselves of what Parkinson's disease is and that's a progressive brain disease and this progressive disease it ends up causing a reduction in the amount of a signaling chemical called dopamine and when dopamine levels are lowered what we really see are a bunch of problems with movement so there are four main movement signs that we kind of talk about when we're talking about Parkinson's disease and we call them the main signs because they're usually the ones that we look for if someone actually has the disease so not everyone with Parkinson's disease will develop all of these signs but most people will at some point in the disease and as the disease worsens over the years of the person has it because remember it's a progressive disease these signs and symptoms usually worsen as well so the first main sign that we'll talk about is a tremor and this tremor usually starts off in the hand or maybe in the finger so a tremor is involuntary shaking and it actually happens because of lots and lots of relaxation Zand contractions in our muscles so you've probably noticed before that your hands can get a little shaky when you do certain things maybe doing something like threading a needle people are always making fun of me for having rips in my jeans so I'm always patching them up and I find that my hands get super shaky when I'm threading a needle or maybe you've noticed it when you've done something like putting eye drops in your eyes but the kind of tremor that someone with Parkinson's disease has it's a lot worse than this it's more frequent and it's more debilitating and we actually have a name for it it's a particular kind of tremor called a resting tremor so a resting tremor happens when the body part is as it sounds at rest and the tremor actually stops when the body part is not at rest so a good way to think about when a tremor would and wouldn't be around is to imagine that you're about to go and grab a pen if you had a resting tremor your hand would be shaking before you went to grab for the pen when it was just resting on the table and this is because the hand would have been at rest you wouldn't have been using it but once you actually started to move your hand your hand and the muscles in your hand wouldn't be at rest anymore you'd be using them and so the tremor would actually stop so this sounds okay you may be thinking okay well I'll just make sure I'm always moving my hand but it's not that easy for a lot of people with Parkinson's disease they actually still have trouble writing because the tremor can return again once they've finished grabbing the pen and they're just holding their hand ready to write so resting tremors are just one of the types of tremors that are out there and so there are lots of other different types that you may see in different conditions or even in just normal healthy people but it's these resting tremors that are the kind that we see in someone with Parkinson's disease so the next main movement sign that we'll talk about is rigidity rigidity basically feels like really really stiff muscles so when someone with rigidity goes to bend their arm say they were going to pick up some food from their plate and put it in their mouth the movement between the plate and their mouth wouldn't be one smooth movement like it normally is so instead it's kind of like that movement happens in a few jerky movements rather than that one smooth movement so we actually have a name for this series of jerky movements that someone with Parkinson's disease has and it's called cogwheel rigidity so we call it cogwheel rigidity because this movement in this case bending the arm it kind of looks like cog wheels moving together in that clunky sorta way you know like the cog wheels that you would see in a grandfather clock for example and this rigidity this feeling of stiffness that causes these clunky movements it's not just a feeling for the person with Parkinson's disease their arm actually is more rigid so it's not just something that's in their head so a third main movement sign is these really slow movements and we actually call this these slow movements brady kinesia where the word brady means slow and the word kinesia means movement so for the person with brady kinesia it can feel like a few different things it can feel like weakness or maybe fatigue or even just this kind of Jen feeling like they can't move the body part that is affected and there are actually lots of parts of the body that can be affected this brady kinesia could happen just in one limb or it can even happen to one whole side of the body and it can even happen to the whole body and this brady kinesia the slowing down of movements actually makes it really hard for the person to complete movements at a normal pace so to kind of picture what this is like imagine the last time you're in a swimming pool maybe you were just trying to walk around from one point to another or maybe you were running in the water because you were trying to catch your friend who stole your ball you can probably remember that walking or running in the water was really slow it takes you a lot longer to to do those movements when you're in the water compared to one year on land and that's kind of what brady kinesia is like so the person can do the movements but they just feel like they're a lot slower so this is quite a bit different than the rigidity that we talked about earlier I often find it a little confusing to think about stiff versus slow muscles they sound kind of similar so the way I like to think about it is I think about our muscles responding to the messages that we send them you know how you tell your arm to move well with rigidity we send a message to our muscles telling them to move and our muscles receive that message and they they start to move right away but because of that extra resistance the movements are just really jerky but with brady kinesia we send the message to our muscles telling them to move maybe we're telling our leg to kick a ball or arm to reach for an apple and our muscles do receive that message but it takes them a while to actually respond to the message to kick that ball or reach for that Apple and it's this delay between us saying to our muscles hey time to move and them actually responding is what makes the movements feel really really slow alright so the fourth main movement side of Parkinson's disease is postural instability being really unstable really unbalanced when standing or trying to move around so we call it postural instability because it's our postural reflexes which are these reflexes that normally help us stay nice and balanced it's those that actually stop working and when these stop working properly that's when someone with Parkinson's disease starts to get really unbalanced and unstable on their feet so postural instability is actually one of the signs that crops up later on in the disease once the person has had it for quite a few years and it's actually one of the most debilitating movement problems that someone with Parkinson's disease can have and this is because that instability that they feel on their feet can make it a lot more likely for them to have a fall and it makes it really hard for them to stay independent and walk around so those are the four main movement signs of Parkinson's disease and other than postural instability they normally start early in the disease and over time they can get a lot worse and that's because the disease as we talked about before is a progressive disease it worsens over the years the person has it and not only can these get worse but they can actually cause a lot of the other movement problems that we see in someone with Parkinson's disease so for example the tremor it can be really subtle earlier in the disease the person may not even notice it themselves but as the disease gets worse over the months and the years that the person has it the tremor can actually get a lot worse and it can even spread to other parts of the body so if it started in the hand or the finger which is really common it can move to the legs even the lips or the tongue so that's something that can happen over time with the tremor and rigidity well rigidity can eventually affect a person's posture and they can actually start to bend over all the time into this stooped posture and this happens because of all the stiffness that they're feeling in the muscles that would otherwise keep them upright and this stooped posture can cause problems as well with the person being bent over all the time this can increase their chances of falling and hurting themselves and because rigidity affects all sorts of muscles in the body rigidity can also cause other problems so later on the person can actually lose their ability to make facial expressions they have trouble smiling or frowning or even showing you how they feel and it's because they don't feel anything it's actually because of all the stiffness that they're feeling in their facial muscles it makes it really hard for them to move their mouth or their eyes so those are some of the problems that rigidity can cause over time and brady kinesia can also cause problems one thing that can happen is the person can actually change the way that they walk the person will start to shorten their stride and they'll start shuffling their feet and the reason this happens is because those slow down movements they just make it kind of hard for the person to step up so high or or step out as far as they used to and one thing that can happen because of brady kinesia much later on after quite a few years is they'll be walking around and everything seems totally fine but then all of a sudden they'll just stop in place and they won't be able to even move themselves and this can last for quite a few seconds and this is because after quite a few years those muscle responses have just become so slow and there's actually a name for this and it's called freezing and we call it freezing because just as it sounds the person actually feels like they're frozen in place like they can't even move and that postural instability that we talked about that can also cause more problems later on what can often happen is the person's balance just kind of it kind of gets worse and worse over time and as this happens they can eventually lose their ability to walk so they may start off just feeling a little unbalanced maybe they can't walk for as long as they normally could or maybe they just need a little help when they're tired but after a while as things get worse their balance is just so bad that they they don't feel safe being upright and they actually may fall quite a bit