”Life is about sports, and sports are about science”. For those of you who enjoy sports, it is recommended that you learn something about knee sports medicine while enjoying the joy of sports, so that you can face inevitable sports injuries with courage and rationality. Of course, while caring for yourself, you can also take care of those around you who have suffered an acute injury as a result of participating in sports. As you know, an acute knee injury is an accident! No one can know when, where, or how it will happen. But once it happens, if it is not diagnosed in a timely and accurate manner, and the injury is severe and beyond the body’s own repair capabilities, the acute injury may be relieved after rest and without your attention, and then suddenly flare up or worsen during a future sport, causing a “small thing to become a big thing”; or it may gradually turn into a chronic injury, causing more healthy tissues. The injury may become chronic, causing more damage to healthy tissue or triggering traumatic osteoarthritis of the knee. Therefore, when the knee is first injured, it is important for the injured person to be able to self-identify the injury. It may be helpful to have the following medical knowledge to help you determine your own injury! ① Identify the history of the injury. For any acute sports injury to the knee, there is a clear history of injury that the patient can identify. This includes: direct impact by another person or hard object, accidental slip, twisting and kneeling, and other mechanisms of injury; ② Pain. Most people complain that the injury was very painful at the time and is memorable and hard to forget! ③ Swelling. A fracture or soft tissue tear within the knee joint will suddenly bleed and the joint will swell up very quickly (usually within 3 hours, if not sooner), accompanied by an increase in skin temperature around the knee joint! Please note that swelling that is obvious after only a short period of time may indicate a “bad injury”! ④ Falling to the ground. Often the person falls to the ground because of severe pain or inability to stand due to inability to hold weight, often with an extremely painful expression. Sweating and crying in pain or rolling around on the ground holding the foot may also indicate a “serious injury”! ⑤ Inability to flex and extend. Injury to the knee joint that does not allow active or passive extension and/or flexion, accompanied by severe pain when moving, may indicate a “mechanical internal disorder” or “joint instability”! This also indicates a “serious injury”! (6) Forced to quit the sport or dance you are participating in. When you are deemed to have a “serious injury”, please contact a knee sports injury specialist promptly to determine whether you need “non-surgical treatment” or “surgical treatment” through professional consultation, physical examination, and relevant radiological imaging to determine the exact diagnosis of the injury. “surgical treatment”. Note: Diagnosis is to clarify the damage caused by the injury to the body! When the injury is within the repair capacity of the body, non-surgical treatment can be used to improve the internal and external environment of the injured knee to promote repair; however, if the injury is beyond the repair capacity of the body, surgical treatment may be required. In fact, this is the principle by which your doctor will arrange your treatment. There are two common misconceptions about injuries: ① If you go to the emergency department and get an x-ray that says “no fracture or dislocation”, is it really okay? Note: The ligaments, meniscus, cartilage and other soft tissues inside and outside the knee do not show up on X-rays and cannot be diagnosed directly! Please be aware of the possibility of missed diagnosis and misdiagnosis. ② If the pain is very painful at the time of injury, and the pain is relieved after a few days of rest, and a few weeks later the walking on flat ground is normal and even jogging is possible, and the swelling is significantly reduced or not swollen, is it really okay? Note that the principles of first aid after an acute knee injury are: Rest, Ice, Compression, Elevation, or RICE for short. Braking and resting after an injury is definitely good for knee injury relief, but it does not mean that the injury has been self-repaired! When the amount or intensity of exercise after the day exceeds the tolerance capacity of the knee joint after the injury, the re-occurrence or aggravation of the injury becomes inevitable! So, please be aware of these two major misconceptions for all sports enthusiasts! Seeking professional medical help after an injury to have an objective and definitive diagnosis determination of the first injury is probably the best option.