Necrosis of the femoral head usually does not have synovial effusion or synovial thickening. Necrosis of the femoral head is mainly caused by ischemia of the femoral head due to poisoning, trauma and other reasons. Patients mainly show symptoms such as pain in the hip and thigh, limping, and shortening of the lower limbs. While synovial effusion is caused by the accumulation of exudate in the joint, synovial thickening is caused by tissue proliferation due to strain and environmental factors. Because the cause of femoral head necrosis, synovial effusion and synovial thickening, as well as the pathological mechanism is different, so the femoral head necrosis generally does not appear synovial effusion, synovial thickening. If you have any discomfort, you should go to the hospital in time, do the relevant examination to clarify the cause of the disease, and then follow the doctor’s instructions for treatment to avoid delaying the condition.