FAI type | Criteria |
---|---|
Cam | ☐ Alpha angle is > 55° ☐ Anterior head-neck offset < 10 mm ☐ Anterior head-neck offset ratio < 0.15 *Must meet 2/3 criteria to be considered cam impingement |
Pincer | ☐ Acetabular depth < 3 mm ☐ Lateral center-edge angle >39° ☐ Acetabular anteversion (in the upper third of the femoral head) < 0° *Must meet 2/3 criteria to be considered pincer impingement |
Mixed | *Must meet 2/3 criteria each for cam and pincer impingement (as per above) to be considered mixed impingement |