In CASI’s reference manual, there is a small section about the Q angle as a key anatomical difference between the typical male and female body types. But exactly what is the Q angle?The quadriceps or “Q” angle is the angle at which the quadriceps muscle meets the kneecap compared to the line formed by the ligament attaching the kneecap to shin. To assess the Q angle: find the pointiest part of the hip bone (ASIS) and draw an imaginary line from here through the centre of the kneecap (patella). Then imagine another line from the bony point just below the kneecap (tibial tuberosity) up through the centre of the kneecap again. The angle between these two lines is the Q angle.

  • Normal Q angle for men is 8 – 15 degrees
  • Normal Q angle for women is 12-19 degrees

This difference is most commonly attributed to womens’ broader pelvis, shorter thighbone (femur) length, and more inwards twist of the femur; however pelvic tilt, foot position and muscle weakness also increase Q angle.

Females have more Q angle, so what? 

Increased quadriceps angle is associated with anterior knee pain in athletic activities, increased risk of ACL injuries; but beyond those more serious consequences, it affects everyday riding by altering the biomechanics of the basic body position.With larger Q angles when the quads flex the kneecap act on the diagonally, and a considerable amount of force is lost as the quads pull the kneecap in an outward direction. To compensate, female riders typically turn the knees inwards, rotating internally at the hip as the knees flex. This causes pronation at the ankle, putting more weight on the medial or “big toe” side of the foot.The end result is the typical A-frame position:

  • The legs are rotated inwards at the hip to maintain position, which results in difficulty steering with the lower joints.
  • Weight is all in the centre of the snowboard between her feet, not evenly distributed along the entire snowboard: reducing her stability and preventing her from achieving board performance.

Can we teach & train to overcome this?Yes! Modification to board setup and stance and improvements to body position can provide immediate results. In the longer term: targeted strength training for female athletes and instructors seeking their next CASI level will help to reduce the effects of a larger Q angle.

Setup: The degree of Q angle can be changed considerably by foot position. In a toes-in position Q angle increases, and the measurable Q angle decreases as the toes are turned out.Female riders may have a natural walking gait where the toes are straight or turn in; and their boards are often set up like how they walk, with very conservative stance angles, sometimes even 0°/0°. Try changing the stance angles of struggling female riders to a more “duck” position: +12°/-12° or +15°/-15°.Also: by going with a wider, more duck stance instead of a narrower stance; female riders are able to engage the muscles of the inner thigh to assist the quads.

Position: Often it’s not enough to encourage a cowboy stance in female riders, particularly when the knees are rotated in and majority of their weight is on the big toe side of the foot: from this position, trying only to “push the knees out” is ineffective. Instead, encourage more even weight distribution across the foot with an emphasis on weight on the outer, or “baby toe” side of the foot, and feeling the sides of the lower leg against the outer side of the boot. This helps to reduce pronation & internal rotation: helping to naturally bring the knees to a more neutral or even cowboy position.

Long-term: Strength training to increase power in the glutes (external hip rotators), to strengthen the core and to balance the quads by strengthening the innermost portion of the quad muscle (vastus medialis) are important for female riders wanting to step up their riding, avoid knee pain and to reduce risk of injury.

Mellen Gorman, BScH, RMT
CASI Level 4 Technical & Education Committee Member

References:
Development of the arch: Functional implications. Thomas C. Michaud, DC. July 2012. Lower Extremity Review.

Unique Considerations Of The Female Athlete. Michael Brunet. Feb 2009. Delmar Publishers Inc.

The variation of the Q angle with different positions of the foot. Olerud C., Berg P. Dec 1984. Clinical Orthopaedics andRelated Research. http://www.ncbi.nlm.nih.gov/pubmed/6499307