Our knee joint is the largest joint in the human body. When we walk on the ground, go up and down, and squat up, it is mainly the knee joint that plays a role. The flexion and extension of the knee joint is the key factor to complete the above actions.
Each of us has knee joint pain symptoms earlier than other joints.
By the age of 50, the knee joint is more or less painful, and some people even have knee pain before the age of 50.
It just caters to the old saying: "Legs get old before you get old."
Why are such important joints more prone to aging?
If we know the reason, we can take care of the knee joint and prevent the occurrence of aging arthritis.
Truth one
Need to control the amount of exercise
Every movement of a human being in a standing position is inseparable from the knee joint.
Walking, running, jumping, squatting, the role of the knee joint is essential.
Normally, the number of steps required for daily life is about 10,000 steps, not counting the steps for exercise.
Therefore, under normal use, the knee joint is already overworked and damaged.
If there is additional exercise, it will have the effect of strengthening the body within a certain range, and if it is excessive, it will accelerate the wear and aging of the joints.
Every day, both knees should be flexed and extended at least 10,000 times under weight-bearing conditions. In addition to the knee flexion and extension activities when sitting and lying in bed, the number of knee flexions and extensions should be about 20,000 times.
The knee joint is so "hard", so people who love sports, people who want to exercise to strengthen their physique, people who want to exercise to lose weight, and people with diabetes who need to exercise to control blood sugar, how can they control the amount of exercise? As for accelerating the aging of the knee joint?
The principle of the conservation plan of our exercise is-it varies from person to person, and from time to time; gradually increase the amount, and stop in moderation.
Everyone is born with a different physique. The bones, joints, tendons, muscles and other sports tissues, as well as the cardiopulmonary system are different in strength, and the amount of exercise that can be tolerated is naturally different, so the same exercise standard cannot be used to measure everyone.
How to master the amount of exercise?
It mainly depends on each person's own feelings.
Every kind of exercise is fine. There is no discomfort in the body during exercise. There is no pain in various parts of the body after exercise, and there may be mild fatigue. The next day there is no feeling of excessive fatigue or rest that cannot be relieved. The amount of exercise at this time is suitable.
With the increase of physical fitness, the amount of exercise can gradually increase.
After the increase, the pain and fatigue can be relieved more quickly, which is the amount of exercise that we can withstand that is conducive to health.
Truth two
Control the weight to reduce the burden on it
Among the four major joints of the shoulder, elbow, hip and knee, which have the greatest mobility of the human body, the knee joint is located at a low level, so the knee joint bears the most weight among the four major joints.
The shoulder and elbow joints are located in the upper limbs. Except for the weight of the upper limbs, they hardly bear the weight. Therefore, the degeneration of the upper limb joints is relatively late, and the degree of cartilage wear on the articular surface is correspondingly lighter.
But the knee joint is different from it. It is a typical weight-bearing joint. It can be said that weight-bearing is the main task of the knee joint.
In particular, not only have to bear weight but also have to move. For example, when squatting up, the quadriceps muscles strongly contract, pulling the patella tendon, and then compressing the patella, causing the articular surface between the patella and femur to bear much more than usual. load.
In the same way, when we go up and down the stairs, the articular cartilage between the patella and femur is also under tremendous pressure.
When going down the stairs, the articular cartilage between the femur and the tibia also bears the impact of the body's downward potential energy, that is, the weight plus the impact, so the damage to the joints when going down the stairs is greater.
Maintenance plan Since the position determines the weight of the knee joint, what we can do is control our weight.
Fat people, that is, people with a large body, will inevitably increase the load on the joints.
Conversely, if you want to reduce the load on the knee joint, you must reduce your weight.
Keep your weight within the normal range, and there is no extra load on the knee joints, and the speed of aging will also slow down.
However, it should be noted that for people with normal weight, there is no need to lose weight.
Because the weight is not as light as possible, too light weight will also affect the strength and stability of the joints.
For example, people who are too light are prone to osteoporosis, so joints composed of bones as the main component will inevitably be damaged.
Specific to the knee joint, osteoporosis will cause the strength of the subchondral bone of the medial tibial plateau to decrease. Just like the foundation of a house is not strong, the cartilage on the surface of the subchondral bone will be unevenly stressed, which will lead to early cartilage degradation.
Truth three
Complex structure to avoid trauma affecting joint firmness
The structure of the knee joint is complex. It is composed of three bony structures: the distal femur, the proximal tibia and the patella. The surface of the bony structure is covered with hyaline cartilage, which can reduce friction and buffer stress, forming a patellofemoral joint and The femoral tibial joint.
There is a meniscus between the tibia and femur, which is a kind of fibrocartilage pad, which increases the contact area between tibia and femur during activities, stabilizes the joints, disperses stress, and reduces impact; there are also anterior cruciate ligaments and posterior cruciate ligaments , The two delicately cooperate to maintain the stability of the knee joint during the flexion and extension process. If the two ligaments are damaged or even broken, it will cause the knee joint to be unstable and accelerate the wear and aging of the joint.
The distal and proximal ends of the patella are connected to the patellar tendon and quadriceps tendon, respectively, and there are medial and lateral collateral ligaments on both sides of the knee joint.
If one of the above-mentioned structures is damaged or the strength of degeneration is insufficient, it will affect the stability of the knee joint and accelerate the aging of the joint.
The maintenance plan cannot be changed. What we can do is to avoid knee injuries as much as possible.
Once the injury is difficult to repair due to its complex structure, it is impossible to repair it completely, which will inevitably lead to a decrease in the stability and firmness of the joint, and the speed of joint aging will inevitably increase.
If you are injured, you need to recuperate fully and try to recover the joints as much as possible, otherwise it will be more difficult to deal with the residual symptoms.
Truth four
Be skinny, keep warm and don’t catch cold
The term "skinny" can not be used to describe the state of the knee joint, without the protection of muscles around it.
Since there are no muscles around the knee joint, and the thickness of structures such as skin ligaments and joint capsules is small, the knee joint is susceptible to cold.
Contraction of blood vessels after exposure to cold will inevitably lead to a decrease in blood flow, resulting in insufficient supply of joints and surrounding structures. After the joints are worn out, they cannot be repaired in time. This will cause the joint cartilage to be easily worn and synovial edema and inflammation.
Over time, irreversible damage to the knee joint develops.
Some people say that Europeans, Americans, Russians, and Japanese people do not have the habit of wearing long trousers, and their knee joints are not bad?
In fact, there are some controversies in this horizontal comparison. The racial physique of Europeans, Americans and Russians are quite different from ours. They are more tolerant of the cold; Japanese people are bare-legged at all times from birth. Perhaps it is this way that they can adapt to the cold early, and their knee joint blood vessels have also adapted to work in cold conditions, and will not be contracted by the cold.
Maintenance plan Our knee joints cannot tolerate the cold, so we must pay attention to keeping warm, especially as the joints age, we need to keep warm.
This is actually the easiest part of joint maintenance.
Truth five
Joint cartilage cannot be regenerated, prevent trouble and repair it in time
The articular cartilage in the knee joint is under tremendous pressure. Impact, friction, instability, synovitis and poor nutrition will affect the integrity of the cartilage. Over time, the cartilage will be cracked, peeled off, and missing, and once the cartilage is damaged to a certain degree, Unable to regenerate.
The best way to maintain the plan is to prevent damage to articular cartilage or strengthen articular cartilage.
Currently, there are drugs that supplement the components of articular cartilage, such as glucosamine, chondroitin sulfate and keratan sulfate.
It has a certain repair effect when the articular cartilage is still healthy or slightly damaged.
This repair is limited and varies from person to person.
Text/Zhang Liang (Beijing Hospital)