Final answer:
Femoral torsion greater than 15 degrees affects knee mechanics, potentially leading to patellofemoral syndrome, with females at higher risk due to their generally wider pelvis and greater Q-angles.
Step-by-step explanation:
Femoral torsion greater than 15 degrees typically refers to an increased angle of torsion of the femur relative to the tibia, which can affect knee mechanics. The Q-angle, a measure indicating how far the femur is angled laterally from the vertical, is normally between 10-15 degrees. A Q-angle greater than 15 degrees can predispose individuals to conditions such as patellofemoral syndrome, due to altered mechanics of the quadriceps femoris muscle on the patella, particularly during knee extension. In females, the propensity for a larger Q-angle is due to their typically wider pelvis, enhancing the lateral pull on the patella and potentially contributing to patellofemoral syndrome. The anatomy of the femur, with a larger lip on the lateral side of the patellar surface, aims to counterbalance this pull and maintain proper patellar tracking.