Patellar part of knee joint

The patellofemoral joint (Patellofemoral compartment of knee joint; femoropatellar joint), is a complex articulation between the patella and the femur. The patella, the largest sesamoid bone in the human body, articulates with the patellar groove (trochlea) of the femur. This joint plays a crucial role in the extensor mechanism of the knee, facilitating knee extension and providing mechanical advantage to the quadriceps muscle group.

The patella is embedded within the quadriceps tendon and is connected to the tibial tuberosity via the patellar tendon. The quadriceps femoris muscle group, consisting of the rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius, inserts into the patella through a common tendon. The medial and lateral patellofemoral ligaments, along with the patellar retinacula, provide additional stability to the joint.[1-3]

The articular surfaces of the patella and the femur are covered with hyaline cartilage, which is thickest on the patella to withstand the high compressive forces during knee flexion. The trochlear groove of the femur is concave, providing a stable track for the patella to glide within during knee movements.[4-5]