Femoropatellar joint

The femoropatellar joint is a sellar joint the articulating surface of the patella is adapted to the patellar surface of the femur. This femoral articulation involves the anterior surface of both condyles. An oblique groove divides it into a large lateral and smaller medial area. The quadriceps muscles, the quadriceps tendon, and the patellar tendon maintain the joint s stability. Its major motions are vertical up-and-down movement on the femur, and movement in a sagittal plane with respect to the tibia. This allows a pulley function during flexion and extension of the knee. 

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