Knee is a weight-bearing joint that must withstand large forces. Knee have a complicated knee structure. Knee injury often occurs together with the injury of nearby tendons, muscles, blood vessels and nerves.
Examples include jumper's knee (Patellar tendiopati) which is an injury that is caused by continuous jumping. Knee pain can be localized to the upper or lower edge of the kneecap, or to the tendon attached to the leg.
Osgood-Schlatter's disease is an inflammation of the mount for the large thigh muscles on the front of the leg bone (tibia) just below the knee. Typical symptoms are pain in the upper part of the fibula because of the continuous activity.
The condition is caused by repeated pull and strain of the large thigh muscle tendon where it is attached to the leg bone. The pain increases with activities involving active use of the thigh muscles (musculus quadriceps femoris), such as jumping, running, kneeling, bending of the knee against a resistance, and when the knee is bent for a long time.