A. Symptoms of meniscal injury: 1. Most patients have a history of knee sprain. 2, at the time of injury, there is a tearing sensation and ringing sound in the knee joint, that is, severe pain, joint swelling, flexion and extension activity dysfunction. 3. Painful knee movement, obvious when walking and going up and down stairs, and some patients may experience knee weakness and locking. 4. When extending and flexing the knee joint, there is a popping sound in the knee. 5.Atrophy of the quadriceps muscle, pressure pain in the knee gap, and inability to hyperextend or hyperextend the knee joint can be found during the examination. 6.Meniscus popping test (McDonald’s evidence): the patient lies on his back, fully flexing the hip and knee, the examiner holds the foot with one hand and places the other hand on the knee, first make the calf inwardly rotate and then abduct and straighten, then make the calf externally rotate and abduct, then inwardly straighten, if there is pain or popping, it is positive. Most of the patients are positive. 7.Grinding test: The patient is in prone position, the affected knee is flexed at 90°, the examiner presses down hard on the ankle and does rotational grinding, and it is positive if there is pain in a certain position. Some cases may be positive. Diagnosis and treatment of meniscal injury: At present, magnetic resonance imaging (MRI) is preferred for the diagnosis of meniscal injury of the knee. Of course, the most accurate diagnostic tool is minimally invasive arthroscopy, just as gastroscopy is the most accurate tool for diagnosing gastrointestinal disorders. Most meniscal injuries can be treated minimally invasively through arthroscopy, including meniscal suturing, meniscal revision, and meniscectomy, with meniscectomy being avoided by most arthroscopists due to its long-term impact on the function of the knee. The first thing that patients should do after a knee sprain is to avoid strenuous activities and avoid all movements that can induce knee pain. 2, such as the above symptoms of meniscus injury, or to go to the hospital in a timely manner, consult a professional arthropist, meniscal injury if not treated in a timely manner, it may further aggravate, and even lead to articular cartilage damage and muscle atrophy around the joint, affecting the effectiveness of treatment and joint function!