Final answer:
The normal osteokinematics for hip ER/IR refers to the range of motion in hip external rotation (ER) and internal rotation (IR). In ER, the femur rotates away from the midline of the body, while in IR, the femur rotates towards the midline of the body.
Step-by-step explanation:
The normal osteokinematics for hip ER/IR refers to the range of motion in hip external rotation (ER) and hip internal rotation (IR).
In hip external rotation, the femur rotates away from the midline of the body. This movement is important in activities such as walking, running, and kicking a football.
In hip internal rotation, the femur rotates towards the midline of the body. This movement is important in activities such as crossing the legs or bringing the knees together.