Q-Angle (Quadriceps Angle)

Last time we spoke about Trcohanteric Bursitis, we labelled some predisposing factors to the onset of this condition. One of these predisposing factors was Q-angles. Below is some more information on Q-angles.

WHAT IS A Q ANGLE?

The Quadriceps angle is the angle formed between the longitudinal axis of the femur, representing the pull of the quadriceps muscle, and a line that represents the pull of the patellar tendon.

HOW DO YOU MEASURE A Q-ANGLE?

Draw a line from the anterior superior iliac spine to the centre of the patella and another line connecting the centre of the patella to the centre of the tibial tuberosity

WHAT IS THE BEST WAY TO MEASURE A Q-ANGLE?

The best way to measure angles accurately is via x-ray. Radiologists and Doctors taking these images are able to accurately draw angles via computer.

WHAT ANGLE IS CONSIDERED NORMAL?

The Q-angle is normally less than 15° in men and 20° in women when the quadriceps are relaxed. The angle becomes smaller when the quadriceps muscles are contracted.

WHAT ANGLE IS CONSIDERED ABNORMAL?

A Q-angle greater than 20° increases the likelihood of injury.

HOW DOES HAVING A LARGER Q-ANGLE IMPACT TROCHANTERIC BURSITIS?

The larger the Q-angle, the more stress is placed on to the trochanteric bursa. The iliotibial band gets pulled tighter which compresses the tendons and subsequently the bursa. This combined with other factors such as gluteal weakness adds compression to the bursa.