There are many causes of knee pain under the kneecap, including bursitis, patellofemoral pain syndrome and Osgood-Schlatter disease, according to WebMD. Knee pain rarely goes away without treatment, and it is not always attributable to one incident, reports Healthline.
Patellofemoral pain syndrome is a condition that is caused by imbalance and tightness of leg muscles, states WebMD. Its symptoms include getting up or squatting after sitting for a long time and dull ache under the kneecap while walking down stairs, notes the UCSF Medical Center. Patellofemoral pain syndrome frequently occurs in athletes and manual laborers, states WebMD.
Knee bursitis is an inflammation of a bursa located near the knee joint, notes WebMD. A bursa is a small fluid-filled pad-like sac that reduces cushion pressure points between the tendons and the bones. Knee bursitis can lead to tenderness and swelling in the area overlying the knee.
Osgood-Schlatter disease is a condition that causes a painful bump below the kneecap in children and adolescents who play sports, reports WebMD. It develops due to reduced flexibility of the calf muscle, hamstring and quadriceps, states Runner’s World. Pain caused by Osgood-Schlatter disease may be mild while performing strenuous activities such as jumping and running, notes Mayo Clinic.