Final answer:
The valgus angle, or Q-angle, is an anatomical feature that dictates the orientation of the knees in relation to the body's midline, with an average range of 10-15 degrees. A larger Q-angle in females, due to a wider pelvis, can lead to more lateral pull on the patella during knee extension, making them susceptible to patellofemoral syndrome.
Step-by-step explanation:
The valgus angle is significant in understanding the knee's orientation and mechanics relative to the body's midline. In humans, the femur bones angle inward, creating what is known as the valgus angle, which is crucial for efficient bipedal locomotion. This inward angling positions the knees and feet directly beneath the pelvis, thus optimizing walking and standing. Females usually have a larger valgus angle, or Q-angle, a measure of lateral deviation of the femur from the vertical line of the tibia, typically between 10-15 degrees. This increased angle is attributed to females having a wider pelvis.
The larger Q-angle affects how the knee behaves during movements such as extension, where the quadriceps femoris muscle pulls the patella superiorly and laterally. Females are more prone to conditions like patellofemoral syndrome due to the pronounced lateral pull of the patella related to their wider Q-angles. To counteract this lateral pull, a large lip on the lateral side of the patellar surface of the femur aligns the patella, facilitating proper knee joint function.