Q-Angle or Quadriceps Angle

Q-Angle is formed by a line drawn from the anterosuperior iliac spine through the center of the patella and a line drawn from the center of the patella to the center of the tibial tubercle. In women, the Q angle should be less than 22 degrees with the knee in extension and less than 9 degrees with the knee in 90 degrees of flexion. In men, the Q angle should be less than 18 degrees with the knee in extension and less than 8 degrees with the knee in 90 degrees of flexion.

 

Anatomical drawing of human hip and knee. Lines show angles from outside of hip to centre of knee and centre of knee to spine.