Fractures & Trauma
The kneecap or patella is the largest sesamoid bone in the body and one of the components of the knee joint, present at the front of the knee. The under surface of the kneecap and the lower end of the femur are coated with articular cartilage, which helps in smooth movement of the knee joint. The kneecap protects the knee and provides attachment to various muscle groups of the thigh and leg.
Dislocation of the patella occurs when the patella moves out of the patellofemoral groove, (called as trochlea) onto a bony head of the femur. If the kneecap partially comes out of the groove, it is called as subluxation and if the kneecap completely comes out, it is called as dislocation (luxation).
Patella tendon rupture is the rupture of the tendon that connects the patella (kneecap) to the top portion of the tibia (shinbone). The patellar tendon works together with the quadriceps muscle and the quadriceps tendon to allow your knee to straighten out.