The difference between internal and external knee rotation is mainly due to the different positions of the foot, the knee, and the walking status.
When the knee is internally rotated, the foot is in an internal eight, meaning that the lower limbs are slightly separated in the standing position, and the anterior side of the foot can be seen to be inclined to the medial side. In external knee rotation, the feet are in the figure of eight, meaning that the lower limbs are slightly separated in the standing position, and the anterior side of the foot is tilted to the lateral side.
When the knee is internally rotated, the knees of both sides can be seen close to each other, while when the knee is externally rotated, the knees of both sides can be seen to be separated in the standing position. In addition, walking with an internally rotated knee is characterized by an inward foot strike, making it easy for the feet to cross, which can lead to falls. When the knee is externally rotated, because of the external eight, the feet are to the sides, and it is not easy to fall. However, both pronounced internal and external rotation can cause imbalance of force in the lower limbs and wear and tear of the knee joints.
The occurrence of knee internal or external rotation, should promptly go to the hospital, under the guidance of the doctor standardized treatment.