hi um now I want to talk about um hand function um to think about hand function we cannot ignore the rows from for the the entire upper extremity so the shoulder complex going to help to uh position the hand in a place that you know the hand needs to to do the task and the elbow allows the hand to move closer or uh farther away from this body and forearm is going of Orient the Palm for prehension or uh object release and the wrist have that final orientation and kind of um position the hand when this hand is manipulating uh stuff or objects and the digit that kind of form um um the demand of the task so these are the coordination of the entire proximity for the hand function so when you think about hand function you cannot just look at the Wren hand it has to be the whole upper exity okay um uh for uh generally uh the hand function can um um be uh seen as grasping and releas and it's really how we use our hand to hold and manipulate object object and we know that you know uh it vary by the size of the object the shape the weight of the object and we have to really consider you know the interaction amount of the shoulder elbow form wrist and hand okay um and not to forget that uh uh we often times focus on the motor function but the sensor the sensory function is really important because if a person cannot sense um the object they cannot have a good uh hand function so for example if you recall uh when we have the um sensation week I ask you to collect um 12 10 to 12 items and kind of um block your uh vision and ask you to collect all the items on the table you see if uh the Sens if a person uh Sensations impaired or lost you know there's no way that we we can finish we can feel and we can uh manipulate the object as we want okay so um so when yeah that's why it's it's so complicated when when we talk about hand function because it it's really the combination of the whole thing uh the molor function and sensation of the whole upper extremity okay so now besides that uh but today's content I want to focus really on really on the hand I mean the wris in hand okay so if you see a term called functional position that's typically U referred to the recent hand position um it um to to be able to hit uh to to function our wrist need to be slightly in extension mcpm and pip in slight fraction and thumb in opposition you may ask what about the dip um dip uh often times it's slightly fraction and sometimes it's in extension and we still we can still function because we can compensate that uh with Pip or mCP motion Okay so again when you um use the term functional position this is the position that um you should be uh referring to okay so now for the grasp or prehension there U generally two type of um um prehension the um we have a power grip which means uh we need more strength to complete that um grasp so uh there are um cylindrical grip that that we hold the bottle as an example or um sperical grip uh grip that that kind of our hand kind of form as a a r shape to hold a ball or a door knob um and the hook grip like we're uh carrying a a briefcase a suitcase okay so these are on the power grip Precision grip is more like a f modor stuff um first we have um Palmer um pinch or um pet to pad pinch uh or pet to side so the pet of the thumb to the side of the index finger pet to side grip also so called a lateral pinch or a key pinch like we holding the key or tip pinch tip to tip pinch and then there's another one called lose imagine that you're holding a hamburger uh that you have that intrinsic plus position that's the lumico grip okay so one of the so the power grip is really um we when we need more strength um to hold an object something so U typically this the fingers wrap in One Direction when the thumb is in the opposite direction like we holding the hammer or um um cutting something that that's that require a lot of force uh in this power grip the fourth and the fifth digit is really important if you recall when we uh last week when I when we talk about the arch when we have that power grip on the fourth and the fifth digit and then the mCP kind of go down the distal transer Char going to change that kind of help uh the individual to have that power grip so uh it's really important that we preserve or fac enhance I'm sorry enhance uh the distal um transfers charge which we consider the fourth and the fifth digit okay so what do you think what muscles are working here for the power grip okay so the first type of power grip I want to talk about is um cylindrical grip again it's like a holding of a bottle or a round shaped stuff um the examples can be holding a hammer um a wheel barrel handle or a grip bar okay sperical grip um is the all five digit kind kind of form around an object that we are holding a ball or a doorknob okay so the key here is the finger kind of spread apart um so examples is like holding an apple a doorknob or supporting a baby's head hook grip that uh that involve the second two uh fifth digit um what's special for Hook is the mCP are mcps are in extension IPS are uh in flection so examples for the hook GP is holding the handle of a suitcase uh or a shopping bag okay so these are um the power grip Precision group um that U is more like we hold the object between the tip of the fingers and the thumb okay so in this sense the intrinsic muscles are more involved than the power grip and uh it require more fine motor or inaccuracy for uh object uh manipulation the first one I want to introduce you is the P to rip it can be um two digigit or three digigit or even four digigit but the key is the pad of the thumb in you know is uh and the other digits pan is kind of pointing to each other in this type of grip the mCP and PP are in flection and thumb is in permer abduction okay um and the tip pinch is like you're holding a needle or kind of squeeze something in so U for the tip pinch uh when you if you look at your hand when you pick up a needle like this your hand looks like you're forming an old position uh compared to the pet to pad you know pet to pad doesn't need to be an O but tip U pinch has to be an O like you're using the tip of the thumb and the tip of any digit to pick up the object so that's the main difference between the pad um the pad to pad and the tip okay so one type of this um U pinch is called three jaw chalk or a pmer pinch is basically you use you know the first three digit and it's going to man manipulate it's also called tripod and often times um it's called pmer pinch so either way um occasionally you may use four digit then that will call that would be call a qu quadrad grip so typically it's three U the first three digit then uh it's that's the person is using the thumb and the index finger and middle finger or you know two fingers to pick up or manipulate an object okay and uh it's quite common that we see the Palmer pinch in writing okay so these are um different type of writing skill and typically when when we refer to uh holding a pen we are talking about fjck Chalk or P pinch okay and then um L pinch is uh we use the pad of the thumb and the uh side of the index finger or the side of any fingers so in this pinch in addition to the the muscles going of working especially the adductive polies and flexis brevis to position uh the thumb U the first dorsal Inus is working here in this uh level pinch okay um so the next one is lumbrical grip so again lumbrical grip is the mCP inflection pip and dip in extension like we are holding a hamburger or holding the uh that's a notepad Okay like this so these are the end function that uh we typically use