The most common causes of meniscus injury walking leg weakness are meniscus tear, knee degenerative disease, muscle atrophy and so on. 1. Meniscus tear: if the patient’s meniscus injury after the meniscus tear, the patient in the walking meniscus compression, which causes walking leg soreness and weakness, may also be accompanied by pain. 2. Knee degenerative disease: due to meniscus injury, it can cause degenerative changes in the knee joint, which will gradually lead to knee pain and activity limitation, and then there will be soreness and weakness in the legs when walking. 3. Muscle atrophy: if the patient is fixed after meniscus injury, prolonged immobilization may cause atrophy of the surrounding muscles, resulting in a decline in muscle strength, and may also appear when walking leg weakness. Meniscus injuries caused by walking soft legs for more reasons, if the symptoms continue without relief, it is recommended to go to the hospital in time to identify the cause of the disease, the doctor targeted treatment.