Polestar Principles Principle 5 Alignment and Weight Bearing of the Extremities Part 2

Let's look at the muscles of the lower extremity. We can divide them into the muscles of the thigh which further subdivides into three compartments. We have the Anterior compartment which consists of the quadriceps, the rectus femoris, and sartorius. We have the medial compartment which consists of the adductors, including the adductor magnus. Then we have the Posterior part of the thigh which consists of our hamstrings- four muscles that help control hip extension and knee flexion. There is something more important than memorizing the origins and insertions of these muscles. I want you to notice, in this particular picture, the relationship of the fascia and the connective tissue around each of the muscles. If you were to stand up right now on both of your legs and reach down with your hands and feel your legs and squeeze them you would notice that they are not that stiff. However, if you shifted your weight onto one leg and lifted up your other leg you would notice that the tone in the muscle increases. In reality, every muscle fiber is enveloped by fascia. Every muscle is enveloped by fascia. Every muscle group is enveloped by fascia. The whole leg is enveloped by the fascia lata including and on the side, the tensor fascia lata, and the IT band. These muscles work in harmony to create enough stiffness all around. If you tried to tell it how much to do you would be wrong. But just from experience, standing on one leg, you will notice it becomes a little bit stiffer in order to balance the pelvis on top of the single leg. When I return to two legs they relax even more- they are not as stiff. It is very dynamic. These muscles work in a very fascinating way as we are walking. There are muscles turning on and off in increments. This muscle works a little bit while the other works as much as necessary to create enough stiffness to maintain balance. Refrain from thinking: "I need to contract my hamstrings now because I am bending my knee in swing phase and I need to use my quadriceps now to kick my leg out." Typically, walking is done by gravity and momentum. We basically use our muscles to decelerate our motion, not necessarily to accelerate our motion. A very beautiful concept here is that our muscles work efficiently around these long bones to try to maintain our uprightness and the efficiency of our movement. If somebody tells me that they are going to recruit their quadriceps, or train their quadriceps, by doing knee extensions in order to perform better, I giggle inside because I know that this is not a functional movement. That is not a functional strengthening pattern. It would be better to just walk or go upstairs or downstairs or run and jump. We would strengthen the muscles with functional activities. This is the way that I look at the body. We see the same thing in the lower leg. We have the muscle groups in the front that are the Anterior tibialis and the extensors of the foot in the toes. On the side of the calf we have the abductors, or the evertors, the peroneus brevis and longus. Posteriorly, we have what we typically call our calf muscles which include our soleus and gastroicnemius and some of the flexors of the foot and ankle underneath that. All of these muscles work in harmony. They are surrounded by fascia. They work in conjunction crossing over multiple joints. Some of these muscles crossover as many as six or seven joints in their pathway. As muscles work in this way there is a lot of intrinsic activity occurring to be able to perform the eversion, inversion, plantar flexion, dorsiflexion, acceleration, deceleration in our legs as we move around or stand. From a muscular standpoint we think of it as a synergistic activity. We are looking at efficiency of muscles by having the bones balanced and properly aligned with gravity pertaining to the activities we choose to participate in. Let's move on to the biomechanics of the lower extremity. We will start with the hip. The hip itself is a ball and socket joint. It is typically a deep socket joint with very strong ligaments. The ligaments and caps around it are meant to be rigid. They are meant to hold that in place because they are so important in the weight bearing. It is important that the cartilage covering the front of the femoral head and the cartilage inside these two bones maintain the congruency that we talked about in the organization of the head, neck and shoulder lecture. That congruency maintains optimal contact of the surface area of the two bones that make up the joint. When we hang on our hips, or when we lean back, the hip can come forward and can cause problems in some of the other structures inside the joint. Now we will look at a slide inside the joint. We will see acetabulum inside. You can see the labrum around the outside of the hip joint. This provides absorption of force and deepening of the socket that allows more stability. If I have poor congruency and poor organization around that hip I can damage or tear the labrum as seen in this particular slide. As we move down the extremity we come into the knee joint. The knee joint is often thought to be a very complex joint because so much of our organization of movement and standing comes from this joint. Remember how I said the medial condial is larger than the lateral condial? This is important to understand. It is like a truck that has two wheels and one is much bigger than the other one. When the wheels spin forward or spin backwards it will create a spiral. It is not a rotation as we would talk about internal external rotation or a physiological movement. It will be referred to as an accessory motion or an altro kinematic. The relationship with that knee causes the spiral. When the knee bends that big medial condial will cause a lateral spiral of the femur. That relationship would cause a reciprocal medial spiral of the tibia. I will repeat that. When the knee bends because that medial wheel is so big it will cause a lateral spiral of the femur and a medial spiral of the tibia. If you go back to Freyette's law, when we take slack up in one direction there is less movement in other directions. In reality, it increases the stability and stiffness of the joint and maintains the congruency of that joint. Now the menisci and the ligaments are protected in that relationship. If I have both of them going to internal rotation or spiraling and I lose those normal mechanics, now I put the ligaments, the menisci, and caps at risk of trauma and injury. These bone rhythms become incredibly important to us as Pilates teachers as we look at alignment of the lower extremity. You can practice this in your labs with your Pilates teachers. When we look at poor alignment of the knee joint or we lose that bone rhythm or have trauma through activities we can tear some of these ligaments. For example, the Anterior Cruciate Ligament seen in this slide or the Posterior Cruciate Ligament in this slide. When we move down into the ankle we look at this complex combination, or a complex of joints and bones that come together. Remember how I said in our picture of the the foot I showed you the foot has this rotation and movement. When we talk about the ankle itself we are looking at what we call the talocrural joint. The crual is the crux, or the cross, between the tibia and fibula and its relationship on top of the talus. The way that I think of this relationship is that the talus of the foot comes up like a post. It looks a little bit like the saddle of a horse. It is wider in the front than it is in the back. When the two bones of the tibia and fibula come over it when I go into dorsiflexion or bend my knees down the thickness will push the tibia and fibula apart and make them stiff. This will give me a lever to be able to propel myself or to push off of when I am walking. If those ligaments are too loose and do not work when I go into dorsiflexion and they mush out that foot will continue to pronate and go nowhere. There is nothing to push me off of the ground. These ligament structures and bony alignment become incredibly important with sports, running, deceleration, and jumping activities. The foot itself has the ability to align and become stiff as we start to toe off. When we see somebody in prolonged pronation where their foot is collapsing we have to look up the chain and see what is going on in the knee and the hip. Is everything spiraling medially instead of having that femur spiral laterally, tibia spiral medialy, and collapsing all that weight into the foot? It is amazing to me when people come in with problems with pronation and we want to put them into orthodics or to do certain kinds of lifts for their shoes. Then we realize that the problem is not about the foot. As we start doing Pilates where we look at the balance and the orientation of the pelvis and the hips first, we quickly realize that weak external rotators in the hip cause the femur to collapse in when they squat. You would see this when they go into a knock knee position. They would lose that alignment and their foot would stay in pronation. If they walk like that long enough they will eventually have trauma and injuries to their feet. In this slide we will see the Bunion, or Hallux valgus which is when the big toe collapses in. This a very common pathology with dancers, women who wear high heel shoes, or people who have Valgus knees, or knock knees, and walk. These people continuously roll over the toe and put stress on the ligaments in the bone. Wolf's Law says that our body will react to the stresses applied to it. The ligaments will become loose and the bones will become hypertrophied due to the stresses that go through those tissues.

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