The “soft leg” to find a doctor early from the Shanghai Sports University, Yang, usually strong, is a well-known basketball expert in the circle. A month ago, he sprained his left knee when he landed in a basketball game, when he heard his knee “pop” and sat down with a weak leg, followed by joint swelling, pain, restricted movement and difficulty walking. Due to previous injuries in sports, Yang did not care too much, after more than 20 days of rest, the symptoms disappeared, he never took this small injury seriously. However, Yang found in the post-injury sports, his left knee joint always appear to “play soft leg” situation, can not force, and usually walking up the stairs also often can not make the strength, due to the weakness of the knee joint led to the gradual atrophy of Yang’s thigh muscles, which as an athlete he really can not stand, which makes him no longer dare to slow down, to the nearby hospital This was unbearable for him as an athlete, so he didn’t dare to slow down anymore and went to the nearby hospital for an examination, and the knee X-ray showed no significant abnormalities in the knee bone. However, Xiao Yang was still unsure, and was introduced by an acquaintance to the orthopedic department of Shanghai Changhai Hospital, where he found a sports medicine specialist, Professor Wang Zimin, who first asked him carefully about the injury and his current symptoms, then had Xiao Yang lie on the examination bed and gave him a thorough physical examination: the “front drawer test” of Xiao Yang’s knee was found to be positive, and the “L-drawer test” was found to be positive. He was found to have a positive “anterior drawer test”, a positive “Lachman test”, a positive “axial shift test”, and pressure pain in the knee joint. Prof. Wang ordered an MRI, which showed an ACL injury in the knee. Professor Wang found that Yang had a clear history of knee sprain, swelling of the knee joint after the injury, and that the left knee joint had the distinctive feature of “playing with a weak leg” after the sprain. The current symptoms are mainly due to the rupture of the anterior cruciate ligament after the knee sprain, which in turn causes instability of the knee joint. 1. What is the ACL and why is it damaged? Yang was confused at first, what is “cruciate ligament”? I just twisted it, how could the ACL break? Professor Wang continued to patiently explain that the ligament is a tough strip of connective tissue that links two different structures, such as two bones, together and is the stabilizing structure of the joint. For the joint, it functions as the reins are for a racehorse and the brakes are for a car; in other words, if the ligament ruptures or fails, the joint is as unstable in motion as a wild horse off the reins or a car with brakes that fail, and if left untreated, it is easily re-injured in a more serious way and leads to wear and tear of the cartilage, eventually causing degeneration of the joint and leaving a lifelong disability. The ACL, including the anterior and posterior cruciate ligaments, is located in the center of the knee joint and plays an important role in maintaining the stability of the knee joint. The ACL prevents the tibia from shifting forward and limits rotational activity, and because the knee often needs to rotate during strenuous exercise, ACL injuries are very common in sports injuries. High-risk sports for ACL injuries include soccer, basketball, skiing, and rugby, while domestic falls on bicycles are also a common cause of injury. The most common mechanism of injury is a non-contact torsional injury, as in Xiao Yang’s sprain, which often occurs during landing or running when the knee joint undergoes excessive valgus and external rotation in a semi-extended state, resulting in a rupture of the ligament. After a rupture of the ACL, the knee joint becomes significantly unstable during movement. If the joint is not treated in time, repeated sprains can easily cause damage to the articular cartilage, meniscus and other important structures, while the instability of the joint and increased wear and tear can lead to premature aging and osteoarthrosis. 2. Why did the injury feel better afterwards, but then worsened after a period of time? Yang then asked Professor Wang, “Why did I feel better 3 weeks after the injury and could go to work, but after a few months of recovery, I felt that my knee joint was not working again, especially when exercising, my leg was always weak, and my leg would be swollen and painful after exercise? Prof. Wang replied that after an ACL injury, the first few weeks are the acute phase because the knee is swollen, painful, and the knee movement is limited. After the acute phase, the hematoma is absorbed, the pain is relieved, and the joint can be moved, so the patient can walk and gradually return to work or school. This is because the anterior cruciate ligament failure has significantly weakened the anti-torsional ability of the knee joint and the stabilizing force that limits the forward movement of the tibia, and the force of the quadriceps muscle will lead to excessive forward movement of the tibia during exercise, and the quadriceps muscle will not dare to make a force, thus appearing The performance of “playing soft leg”. Due to the pain and instability of the knee joint, a considerable number of patients have to give up their beloved strenuous activities such as soccer and basketball with pain; worse still, the quadriceps muscle develops disuse atrophy. Some patients who have recovered for a period of time can continue to play sports, but often re-injure themselves during sports, causing secondary injuries to the meniscus, collateral ligaments, and other important mechanisms of the knee. Studies have shown that medial meniscal injuries and knee degeneration are significantly more likely to occur in knees with ACL failure. 3. Why was it not diagnosed to begin with? Yang wondered why his ACL injury was not found even though he went to the hospital after the injury and the doctor took a film. Professor Wang answered: the chance of missing the diagnosis after ACL injury is higher. This is because, on the one hand, patients can still walk after the injury and lack the knowledge to do so, so they think they are well and do not go to the hospital; on the other hand, because ACL injuries are difficult to detect on X-rays and have to be combined with clinical examination and MRI to confirm the diagnosis, and in the acute stage, due to knee hematoma and pain, patients are often not able to cooperate with the doctor to do clinical examination, so inexperienced doctors will The inexperienced physician will easily miss it. However, experienced sports medicine specialists know that in the acute phase of a torsional knee injury, if the joint is swollen and hemorrhagic, there is a 70% chance of an ACL injury, which can be diagnosed early with an MRI. If an MRI is not possible, after 3 weeks, when the hematoma is absorbed and the joint resumes movement, clinical tests such as the Lachman test, axial shift test, and drawer test can also help confirm the diagnosis. In some primary care hospitals, the diagnosis is easily missed due to the lack of appropriate equipment. So when the knee is obviously swollen and blood accumulates after a knee sprain, and a few weeks later there is instability in the knee joint during sports and playing soft leg, you should think of an ACL injury. 4, how should I treat after an ACL injury? Xiao Yang dawned on him, no wonder his knee always has no strength, good thing he ran into an expert today, Xiao Yang hurriedly asked Professor Wang what the next step is to treat. Professor Wang’s advice was that he would have to perform an arthroscopic ACL reconstruction surgery. Xiao Yang was nervous when he heard that he had to undergo surgery. He said he did not understand how a small ligament injury could require surgery. Professor Wang then explained: This is because after the ligament injury, on the one hand, due to poor blood supply injury after conservative treatment is difficult to heal on its own, on the other hand, the ACL plays an important role in maintaining the stability of the knee joint, without the ACL knee in the movement is like riding on a horse without reins running, the movement leads to knee instability, and can easily lead to knee cartilage and meniscus and other important structures Only surgical treatment can allow patients to return to sports and fundamentally improve their quality of life. Furthermore, surgery should be done as early as possible, and studies have shown that patients who have an ACL injury for more than 6 weeks before surgery are 4 times more likely to have a medial meniscus injury compared to those who have surgery within 6 weeks of injury. Therefore, younger patients should undergo minimally invasive surgical treatment sooner after an ACL injury to ensure maximum recovery. Those patients who delay surgery have a much higher chance of developing sequelae. 5.Can I have minimally invasive surgery? Despite the benefits of surgery, many people are still filled with fear and anxiety. In fact, ACL surgery is not scary, it is just a tendon graft (either your own or allograft) to replace the torn ligament, which is called “ACL reconstruction” in medical science. With the current advanced medical technology, the surgery can be done with a few holes in the knee joint and only a small incision at the tendon, so it is a minimally invasive surgery with little risk and an aesthetically pleasing wound that can be discharged in three to five days. Arthroscopic reconstructive surgery has many advantages: (1) Less invasive. Arthroscopic surgery does not need to open the joint capsule, but operates through several small incisions of several millimeters into the joint, leaving only a 2-3 cm incision at the site of the tendon, which is truly minimally invasive surgery. (2) Accurate diagnosis: Under the direct observation of the arthroscope, all kinds of lesions in the joint can be seen and diagnosed accurately. (3) Precise operation. The arthroscope is like a magnifying glass, which magnifies the structures in the joint and makes the operation more precise. (4) Complete treatment, arthroscopic surgery can treat all aspects of intra-articular lesions through different angles of access, leaving no dead ends, while traditional incisional surgery can only treat localized lesions in the joint due to the limitation of incision, and easily misses lesions. (5) Fast recovery, because of the small trauma, postoperative recovery is fast, simple surgery the next day can live on their own and discharge, complex surgery generally only need to be hospitalized 3-5 days can be discharged, no blood transfusion, the patient’s costs are also correspondingly saved. (6) Beautiful appearance, compared with traditional incision surgery, the incision is smaller and more beautiful, more easily accepted by beauty lovers. 6.Minimally invasive surgery, how is it done? Professor Wang’s patient and detailed explanation made Xiao Yang relax and decide to undergo the surgery after discussing with her family. Professor Wang performed an arthroscopic ACL reconstruction surgery on Xiao Yang at a later date. During the surgery, Professor Wang introduced the arthroscope into the knee joint through two small holes in the front of the knee joint, while using a special probe hook to explore the structures inside the knee joint. The anterior cruciate ligament in the center of the knee was completely torn at the end of the femur, the ligament was atrophied due to prolonged tensionlessness, the synovial membrane in the knee was congested and edematous, and the meniscus in the knee was also damaged. Professor Wang first sutured the damaged meniscus as quickly as possible, then made a small incision below the knee joint and removed two N-cord tendons for braiding and processing before use. First, Professor Wang skillfully used a medical planer and plasma knife to clean up the hyperplastic and obviously congested and edematous synovial tissue, and using the most advanced technology available, he preserved the stump of the original ACL, only the femoral stop of the ACL was exposed, and the two points of the femoral tunnel inlet were predetermined, which was the first step of the surgery. The second step of the procedure is the creation of the reconstructed ACL tract in preparation for the introduction of the reconstructed graft. The tract is positioned with specialized positioning instruments and the tract is created according to the diameter of the braided tendon. Professor Wang used the most advanced anatomical double-bundle reconstruction technique, drilling two tunnels in each femur and tibia. This is a very important step that determines whether the reconstructed ligaments will stabilize the knee joint and function properly in the joint cavity, which requires a high level of skill and experience. The third step is the introduction of the prepared reconstructed graft along the bone tract. After the reconstructed graft is introduced into the bone tract with uniform force, the femoral end of the graft is fixed to the femoral surface by a pre-installed button plate, and after repeated pre-tensioning within the knee joint where the reconstructed graft is performed, the tibial end of the graft is fixed to the tibial surface with absorbable compression screws, and the excess can be reinforced by fixing it to the tibial surface with portal nails. The surgery was completed with one suture on each side of the posterior knee incision and three sutures in the longitudinal incision of the upper calf. The entire surgery took only about an hour and went very smoothly. On the second day after surgery, Yang felt a significant reduction in his knee symptoms and was discharged from the hospital two days later to undergo rehabilitation with the aid of a special brace according to Professor Wang’s plan. 4 months later, when Yang came to Professor Wang’s clinic for a review, he told him that he was basically cured. The weakness in his knee disappeared and he was able to jog and do other physical exercises, and his daily work and life were not affected at all. Xiao Yang is only one of the thousands of patients with cruciate ligament injuries that Professor Wang has treated, and he is very satisfied with his recovery after surgery. Professor Wang and his team are helping more patients to relieve their pain and improve their quality of life through the professional treatment of cruciate ligament injuries. 7.Can ACL injury be prevented? Surgery is successful, but it is still an injury after all; a reconstructed ligament is not as good as the one given by parents. Here Professor Wang reminds us that in daily life, especially in sports, we should try to avoid non-contact knee sprains. The following factors are involved in non-contact injuries of the ACL: ① Landing on one leg with the full foot on the ground fixing the tibia of the lower leg. ② Small angle flexion of the knee joint near the extension position. (iii) Knee valgus occurs. ④ When the quadriceps muscle fires, the N cord muscle (mainly the biceps femoris) is not effectively counteracted, resulting in excessive anterior displacement of the tibia. The following measures are considered to help prevent ACL injuries: 1) adequate warm-up before exercise; 2) training athletes to have sufficient forefoot support time, greater than 40ms, when landing, so that the tibia will move with the femur during the “probable injury time” to avoid excessive rotation and excessive forward movement. 3) training athletes to land at a relatively 4) Train the athlete’s N cord muscle (mainly the biceps femoris) strength to effectively counteract the quadriceps.8, Summary “Early diagnosis, early treatment” is especially important for ACL injuries. Many people (especially young people now) in the knee sprain, thought it was just a simple pain, swelling for a period of time, rest will be fine, until the pain and swelling disappeared, the phenomenon of the knee “playing limp” also did not cause attention, still with a knee brace or other protective gear for work or sports, so that the knee sprain The unstable knee joint continues to undergo abnormal wear and tear, causing damage to the cartilage and meniscus in the joint and accelerating the degeneration of the knee joint. Therefore, after a knee sprain, you should actively go to a major hospital for consultation and examination. If an anterior cruciate ligament injury or other ligament injury is found to be compatible with the indications for surgery, arthroscopic minimally invasive treatment should be performed early to perform reconstructive surgery of the ligament. After the surgery and systematic rehabilitation, the patient can basically recover the function.