The most typical manifestation of ischemic necrosis of the femoral head is hip pain. The pain can occur suddenly or get progressively worse and can have some precipitating factors such as a sprain of the hip (which is mild) or no precipitating factors at all. The initial pain lasts from one day to several days or longer. The pain may be relieved after rest, and sometimes the pain may persist for a long time after the initial pain relief. Later, the pain can be mild or severe and gradually worsen until it cannot be relieved even after rest, indicating that the condition has entered the middle and advanced stages. The pain often occurs around the hip joint: in the inguinal region, in the greater trochanter or in the anterior upper part of the thigh, or in the middle and upper part of the thigh. Sometimes there is only pain in the knee joint area, which is very likely to cause a missed diagnosis. Clinical manifestations of ischemic necrosis of the femoral head: Initially, there is only mild restriction or no restriction of hip joint movement, but in a few patients, the pain in the hip joint is heavy at the beginning, and the restriction of movement is also obvious. When the pain is relieved, the limitation of activity can be reduced, but as the disease gradually worsens, the limitation of activity gradually increases, until the limitation of hip joint activity is very serious. This indicates that the disease has entered the middle and advanced stage.