A knee injury refers to damage to any part of the knee joint, including ligaments, cartilage, or bones. Common types of knee injuries include sprains, strains, and tears, often resulting from sports activities, falls, or accidents. Symptoms may include pain, swelling, stiffness, and difficulty in moving the knee. Treatment for knee injuries typically involves rest, ice, compression, and elevation, known as the RICE method. In more severe cases, medical intervention such as physical therapy or surgery may be necessary. Proper rehabilitation is essential for recovery and to prevent future injuries.