It is common to encounter people with knee pain. Some of this pain is transient, and some of it can last for years or even decades. In people with knee pain, there tend to be more women than men, more fat and heavy bodies than thin and light bodies, and more elderly than young people. Why this is the case, the author believes, is that these people are prone to injury. It is the purpose of this article to explain the reasons for this susceptibility to injury. The reasoning is simple, but some of the content is not the medical textbooks can think of.
I. Species comparison.
Among vertebrates that move with all four limbs, only humans walk with their hind limb bodies. In all four-limbed animals, the forelimbs are alternately supported in their activities. When walking, the hind limbs also alternate. When running, the hind limbs fire simultaneously, equivalent to jumping in humans. However, the knee joint is not fully extended (neither is straightened) during the activity, regardless of the time of day. Humans not only walk upright with their hind limbs, there is a process of straightening the knee during walking, while also generating swaying from side to side. In this way, almost all vertebrates that move on all fours have a much lower chance of knee injury than humans. They are prone to injury mostly in the human equivalent of the wrist and hand and foot parts.
Second, the limbs are not symmetrical, and there is a division of function.
Human organs and limbs are not produced in a factory, but are gradually developed and formed in the mother’s body. In the development of many factors interfered with, many people’s limbs are only roughly the same, not completely symmetrical and equal. About half or more of the people have lower limb bones that are not exactly equal in length. Some people have long thigh bones on one side and equal calf bones on the other; some people have long calf bones on one side and equal thigh bones on the other. In some cases, even though both lower limbs are equal in length, the knee joints are not at the same level when standing upright (one femur is long and the other tibia is long).
In people with such limbs, the burden of weight-bearing activities is often greater in one limb than in the opposite limb, although there is no significant limp in walking.
Even in people with symmetrical lower extremities, one limb has a greater weight-bearing activity than the other due to the natural division of limb function on both sides. For example, people with right-handedness (right-handedness) have a better range of motion and flexibility of the right lower limb than the left. The left lower limb has more weight-bearing work than the right lower limb, and the left foot is slightly larger than the right foot (Oh, buy shoes to try on with the left foot, no need to try on both feet). Jumping force in the left lower limb, high fall or jump to the ground, are the left lower limb first contact with the ground, the left knee, ankle, heel injury opportunities than the right side. Even if they are injured at the same time, the degree is much heavier.
Third, embryonic development determines the strength of physical fitness.
A person’s physical strength is determined in the embryonic period that is good. The so-called physical strength is not the size and strength of the body after birth, but the ability to repair injuries and the degree of fatigue damage to body organs and tissues. In this regard, men are better than women, teenagers are better than young adults, and young adults are better than old adults. Physical strength stems from the body’s ability to produce cholesterol (you know the benefits of high cholesterol).
Many people show physical weakness at an early age compared to others. For example, children (mostly preschoolers) who often cry at night about knee pain are the most common sign of weakness. Even as adults, these children will be more prone to knee and other pain than others. This is because their tissues are less able to tolerate fatiguing injuries and to repair themselves after injury.
Fourth, joint movement.
As mentioned earlier, only the human knee joint needs to move from flexion to full extension in every movement activity. Therefore, the range of patellar movement in humans is greater during knee extension than in other four-legged vertebrates. The chance of injury to the soft tissues surrounding the patella is much greater in humans than in them. They are more susceptible to injury. Therefore, many people have anterior knee pain, such as those who walk with weight, those who bounce repeatedly on hardened surfaces, and those who climb (up and down hills or stairs) (see my article on the principles of anterior knee pain for more details).
In vertebrates other than humans, who move on all fours, because the knee joint is not fully extended, the swaying during walking occurs mainly at the hip (hip joint). In humans, the sway is mainly in the knee joint. The knee joint in extension is not as stable as the knee in flexion, and the joint capsule walls (joint capsule and extracapsular fascia ligaments) on both sides of the knee are easily damaged by fatigue due to the pulling of the femoral condyles from side to side (see my principle of medial knee pain for details). For example, fat and heavy people, elderly people, etc. All tend to have pain here.
In human running, due to the leap after stirring the ground, reducing the degree of extension of the knee joint, walking and running compared to walking is more prone to pain in the back of the knee. In humans, during walking, due to the stretching action, the muscles and fascia behind the knee are repeatedly stretched by the ground resistance in the extended state, producing a fatigue injury (see the principle of posterior knee pain I wrote about for more details).
By what has been said above, we can know the reason why some people will have knee pain, while others will have almost no knee pain throughout their lives. The innate structure of the body and the degree to which the body can tolerate fatigue (material strength) determines those who are prone to knee pain.
The cause of knee pain is injury, and most people have fatigue-related knee pain. Once you know the cause of the pain, treatment is simple. It is that knee pain can be cured by keeping the knee joint in a pain-free state for a period of time, regardless of gender, age, or race, during the period of pain.
Explanation of knee pain or increased pain when it gets cold.
Many people experience knee pain, or worsening of existing pain, when the weather gets cold. How do you explain this phenomenon?
My explanation is a little different. I believe that human beings are also living creatures, with characteristics of both animals and plants. What I said before are the characteristics of animals. Now let’s talk about the characteristics of plants.
People can grow up from childhood, and broken wounds will heal themselves into scars. These growth characteristics are plant characteristics, so they are also sensitive to temperature, just like plants. At the right temperature, growth and metabolism are faster. At low temperatures, the growth and metabolism slows down. This is the reason why wounds recover quickly in spring and summer and slowly in autumn and winter after injury.
The knee joint, because of its frequent activities, many times has an injury that is not felt to exist, and not feeling it at the appropriate temperature is not the same as not feeling it at the inappropriate temperature. Therefore, it becomes apparent when it changes from warm to cold.
The ancient Chinese attribute this to cold is not justified. If cold causes illness, it should be in the whole body and not in a particular knee joint. The reason for the pain in one knee joint is because that knee joint itself is injured and the low temperature is not suitable for growth and recovery. It is the knee joint itself that is the problem, not the general environment. The solution to this problem is simple, just wear more, pay attention to the warmth season, and keep your clothes at the right temperature for injury repair.