Symptoms of infrapatellar fat pad inflammation include pain during knee flexion, patellar ligament tenderness, and knee eye swelling. 1. Knee flexion pain: when performing knee flexion movements, such as squatting or walking up stairs, knee pain may appear, which can be relieved after resting. 2. Patellar ligament compression pain: pain may appear when pressing the patellar ligament, and the symptoms are obvious when the knee is flexed. 3. Knee eye swelling: the fat pad is located between the patella and the tibia, in trauma, chronic strain injury and other factors can cause the fat pad to undergo aseptic inflammatory reaction, causing the fat pad to swell, and in the later stage can lead to knee eye swelling. The infrapatellar fat pad stabilizes the knee joint and reduces knee friction. People who perform knee flexion exercises for a long time, such as skiers, are prone to this disease. If the above symptoms occur, it is recommended to go to the hospital in time for early and regular treatment.