What's going on when my knee suddenly hurts?

When your knees always hurt suddenly, you must not ignore it, because many factors may cause the pain, such as traumatic synovitis of the knee or osteoarthritis of the knee, which can cause pain symptoms.

1. Meniscus injury Meniscus injury is a common injury among athletes. When the lower limbs are weight-bearing, the feet are fixed, and the knee joints are slightly flexed, if the knee is suddenly excessively internally rotated or externally extended (for example, in volleyball, when a player suddenly turns around and dives to save the ball while defending), it may cause a meniscus tear. Meniscus injury will cause an obvious tearing feeling in the knee, followed by joint pain, limited movement, and limping when walking. The joints show swelling and a feeling of slipping, and there is a popping sound when the joints move. ?

2 Traumatic synovitis of the knee The synovium of the knee is one of the main structures of the knee joint. Synovial cells secrete synovial fluid, which can keep the articular cartilage surface smooth and increase the range of joint motion. When the synovium is damaged due to trauma or excessive strain, a large amount of fluid will accumulate, increasing the pressure within the joint. If it is not eliminated in time, it can easily cause joint adhesion and affect normal activities. Patients will feel pain, swelling, tenderness in the knee joint, and a frictional and astringent sound in the synovium. The most obvious characteristic of pain is that when the knee joint is actively and extremely extended, especially when the knee extension movement is performed with a certain resistance, the pain below the patella will be aggravated, and the pain will also be significantly aggravated during passive extreme flexion. ?

3. Osteoarthritis of the knee is a disease that is more common in middle-aged and elderly people, mostly women. Excessive weight load is the main cause of disease. The knee joint will be swollen and painful, and sometimes there will be a grinding sound when moving the joint. The knee may develop a varus deformity with medial pain. ?

4. Knee ligament injury: The stability of the knee joint is relatively poor when it is slightly flexed. If it is suddenly subjected to external force and causes eversion or inversion at this time, it may cause injury to the medial or lateral collateral ligament. Medial collateral ligament injuries account for the vast majority of clinical cases. Taking this injury as an example, the patient will have a clear history of trauma, pain and tenderness on the medial side of the knee, pain that worsens when the calf is passively abducted, swelling on the medial side of the knee, and ecchymosis after a few days. Knee joint movement may be restricted. ?