Patella

A small, flat bone located in the front of the knee joint.

The patella, commonly known as the kneecap, is a triangular-shaped bone situated at the front of the knee. It serves as a protective shield for the knee joint and is connected to the quadriceps muscle through the patellar tendon, allowing for efficient movement and support of the lower limb.

Terminologia Anatomica

patella

System

Skeletal system

Function

The primary function of the patella is to facilitate movement and assist in the proper functioning of the knee joint. By acting as a fulcrum for the quadriceps muscle, the patella increases the leverage of this muscle during knee extension, enabling greater force to be applied when straightening the leg. Furthermore, the patella plays a crucial role in protecting the knee joint from injury and mechanical stress during activities that involve running, jumping, or squatting. Its articular surface also helps in smooth movement against the femur during flexion and extension of the knee, minimizing friction and wear on the underlying bone structures.

Location

The patella is uniquely positioned within the knee joint. It is located at the anterior aspect of the joint, where it rests in a groove formed between the femur, known as the trochlear groove. It is embedded in the tendon of the quadriceps muscle and lies approximately in the midline of the body, just superior to the tibia, ensuring its alignment with the lower limb's motion. When the knee is flexed, the patella glides upward and downward within its groove, allowing for a range of motion while maintaining its protective function.

Did You Know?

The patella is one of the largest sesamoid bones in the human body, meaning it is a bone embedded within a tendon.
In some individuals, the patella can be classified as a bipartite or tripartite structure, meaning it is made up of two or three separate bones instead of one.
The patella is vital for efficient walking and running; without it, significant force would be lost during these activities.