now let's talk about gate before we talk about the gate cycle uh we need to um understand some terminologies that are commonly used uh in uh our practice the first one is Step length step length is the distance between uh the two different leg so uh um right leg to uh the left leg and the right heel to the left heel right here uh it is it is different from the stri length stri length is basically the same leg the distance between the same leg so roughly um the heel of the left um foot right here and then the next uh heel of the left um foot on the ground so this is the stride length and also uh there's a term called Step width uh it is the center of uh uh one leg and uh and the distance from the other leg so this this is step with and this is important because it represent the base of support of a person doing uh the gate cycle the gate cycle has two phases um St phase and swing face and the terminology to describe the gate um has been changing so traditionally we we uh start from the heel strike which uh one leg of the heel start to touch the ground and then uh foot uh uh flat uh that's also uh the loading response that so that the stance leg limb or leg start to take uh load and then we Swift our body weight to the Sten uh lim that's called mid stance and then um the heel off and we start to push off our body way too the other side so and then toe off and then the uh the leg is off uh the ground we have initial swing mid swing and terminal swing and then it'll go back to uh initial contact so I'm listing the two um different terminology here so that um that hopefully uh that help you understand um the differences and hope you understand the situation of the gate uh cycle this is a uh figure of uh the entire gate cycle here and I'm going to use this to describe the whole um gate cycle um um for each uh faces so um we will focus on one leg and basically a gate cycle described on one leg and there's a whole book talking about uh gate cycle and I'm not going to do that but I will point out some key features and what uh what muscle are in charge of this kind of movement at that stage uh we start from um initial contact or a heel strike in this phe uh this person uh start to you know touch the ground uh the key feature here is the body weight begins to shift over to the stance uh limb at this at this stage the hip is uh 20° of of flexion knee slightly flexed to 5° and ankle is in zero which is zero um tosif flection right here and then we we move on to the next stage uh of loading response so The Stance leg starting to take a body weight and at this stage because we are uh taking the load right so we um the knee have a a huge role in in this phase because the Knee will take the the shock um the loading uh greatly so in this uh stage Hep uh flexing in 20° but don't uh don't forget uh we are uh moving our body from the uh the other leg to this St leg right so the hip is moving it can be rotation to uh from the left to the right and also um and some tilting going to happen so in this stage the hip extensor and um is trying to stabilize the lower extremity and then uh stabilizer um they're trying to uh maintain the body alignment so that this person can shift the body weight to The Stance uh LM and the knee extensor uh which is the quadriceps has a lot of role in this and and be careful then uh the qup is doing Ecentric contraction because um this movement is moving with gravity right so uh quadricep has to um contract eccentrically to stabilize the lower extremity and also um the this person 's ankle move from doif flexion to PL flexion right so doif flexor uh will uh contract eccentrically to prevent the foot from a flopping if we recruit um the pl of flexer then the food will flop quickly and we don't want that and then we continue to shift our body weight to uh the the Sten limb right here and this is uh where the hip is in neutral and the knee is slightly flexed and um so now ankko is uh is having a a major role here because we need to prevent our body from you know uh falling forward so in this in this situation the plant flexor is uh Contracting eccentrically to prevent that um from happening and then we move on to the terminal stance or heel off in this phase uh we uh we are starting to uh shift our body away from stance LM to uh the other leg so you can see that at this at this stage uh the person's hip is uh in 20° of um hip extension and 5 degrees of knee flexion and ankle in 10° of dosy flexion and then we start to um enter the toe off or uh pre swing phase and this is the phase that uh we uh put a lot of um emphasis on the ankle because um the goal is to uh have the food uh uh clear from the ground so in this in this situation um uh we will recruit the pl of flexer to um to push off our body um against the floor and because we um we count on a plal flexor a lot and this um pental flexor also contributing to the knee uh flexion um and then we move on to um the initial swing phase in the initial swing phase the goal is to uh rise up the leg and then move keep moving forward so in this situation uh if if we go back to uh the pre swing phase the ankle was uh in 15° of pla flexion and then move and then knee was in 40° of flexion right and then in this phase the ankle um is doing p uh a doive flexion from U 10° uh 15 degrees of PL of flexion to 5 degrees so and then on the hip the knee the ankle uh flexors are doing uh concentric uh contraction and then we move on to the mid swing here so our body continue to uh move the swing leg forward uh um one key uh feature here is to pay attention to the knee of flexion right here so at the later part of the knee flexion because the our body needs to prepare on the lending right so in this situation the uh the knee flexor uh which is a hamst stream has to uh contract eccentrically just to prepare uh um for the landing and by controlling the knee um doing um controlled extension and then we move on to the terminal swing phase and this in this phase we um we also need to uh slow down the um the speed so that we can have a safe landing right so in in this in this uh phase the hamstring has a a key role here so these are um the whole uh gate cycle because is um after the terminal swing phase we will uh restart another initial contact so understand a normal gate cycle would help us uh when we analyze our client's gate cycle here and um to do uh the gate analysis there's a whole book talk about it so uh but here I'm going to touch uh superficially so we understand the key rowes of each joint and with what uh key muscles um that are in charge of this um so there are two different gate pattern that I uh want to introduce you the the first one is step to gate and the second one is Step through gate step two is say I step my right foot out and my left kind of match to the same level of my right that's the step two gate step through is when I have my left uh out and my right is kind of passing it that's step through gate um and there are uh also a different kind of uh gate pattern um that people use so I'm going to start from this fourpoint Gates right here say uh we have a client who has uh both crotch on each side so um so this person have four points of contact right so one crutch on the involved side involved leg uninvolved lag and U clutch on the uninvolved leg uh leg so these are the four uh points of contact when we talk about patterning that's different because when we talk about gate patterning uh we actually counting at how many limbs are swinging so in this situation if we have a fourpoint gate then this person is moving one point at a time so you know this's four point gate going on if I uh have both crotch on on on both side and I have one leg so I have uh three points of contact right and when I move I move one side of the crotch first and then the other and my leg that's three point gate if I move both crotch together and my leg then I'm doing a two 2 point gate so please don't be confused with the uh points of contact versus uh the uh Point gate in the referral we may see these terms so we need to be familiar with these terms nwb stands for nonwe bearing that means uh no weight can put on that limb 50% we bearing or partial we bearing that means they can uh tolerate uh partial or uh web bearing is tolerated and uh we may see uh the instruction says full web bearing in this situation our client are free to uh put their leg on the ground and take full well bearing however um in reality we may have a full web bearing uh instruction but they are not doing it we need to do a lot of Education to educate them that it's okay to put your weight on the uh effective limb when we when when we do training um there's a common phrase that we use so say uh when we are uh doing the um training on the stairs when we go up the stairs we we ask a client to put or on under their unaffected leg first when they're descending or uh going down the stairs they uh the first leg that they put is the uh injured or uh effective uh leg um these are some deviation Gates that we may see in our common practice uh Caesar Gates is commonly seen for people with uh cerebral py and the reason for them to demonstrate this Caesar gate is uh the tight hip adductors another gate we will see uh is Hy pic gate uh commonly observed in people post stroke and that because they uh uh one side of the body um is weaker another um gate is uh shuffling gate or or AKA Parkinson's gate that's because um uh they lean their body forward to initial uh to initiate the the the gate cycle um but and then that force them to shuffle a lot and quicker so that's that our client May demonstrate this kind of shuffling gate uh and you may also see volting gate um in uh your practice that's often times is the knee is fused and to compensate that um um The Stance leg may rise up so to allow the swing uh limb to to pass so this um you may these are deviations that you may see in our uh practice