Patella alta

A flexion deformity of the knee is the inability to fully straighten the knee. A synonym for it is flexion contracture. Normal active range of motion of the knee is 0° extension and 140° flexion. In people with a flexion deformity one of them or both are reduced. It develops as a result of failure of knee flexors to lengthen in tandem with the bone, especially when there is inadequate physical therapy to provide active and passive mobilization of the affected joint.[1] They often requires an extensive rehabilitation. [4] In most of the cases flexion deformities occur bilateral.

The knee joint consists of three bones, the femur, the tibia, the fibula and also the patella which is a sesamoid.

The patellofemoral joint is the portion of the knee joint between the patella and the femoral condyles. The patellofemoral articulation totally depends on the function of the quadriceps. The quadriceps muscles are connected to the patella with a shared tendon. The quadriceps femoris is divided into four different muscles with the same insertion on the patella: the rectus femoris (RF), the vastus lateralis (VL), the vastus intermedius (VI) and the vastus medialis (VM). There is also a tendon that connects the bottom of the patella to the tibia, called the patellar tendon. This tendon is extremely strong and allows the quadriceps muscle group to straighten the leg.