I understand that: Pronation – IR tibia – genu valgum – IR femur – anterversion – coxa vara. But TherapyEd, Magee and Wikipedia says genu valgum results in lateral tibial torsion (TherapyEd: genu valgum/varum description in lower extremity conditions). Is torsion and rotation of the tibia different? Also, could you please explain wrt intoeing and outtoeing of the foot also. Thnx. Please tell me if this concept is right or wrong.

When used to refer to the lower limb kinesiology/kinematic chain, ‘torsion’ and ‘rotation’ are often used synonymously. Although in a strict sense, they both have different meanings.

Torsion; the action of twisting or the state of being twisted, especially of one end of an object relative to the other e.g. squeezing a towel.

Rotation; the action of rotating about an axis or center.

The terms ‘medial’ and ‘lateral’ refer to the direction of the twisting. Lateral tibial torsion (or external tibial torsion) is the outward twisting of the tibia and is often associated with genu valgum. Media torsion is the inward twisting of the tibia and is the most common cause of in-toeing. It is usually seen at age 2 years. Males and females are affected equally and about two thirds of patients are affected bilaterally. Whereas medial torsion improves with time, lateral torsion often worsens because the natural progression is toward increasing external torsion.

Reference 1