External Rotation

External Rotation (Lateral Rotation): A rotational (spinning) movement in which the anterior side of a segment moves away from the midline of the body in the transverse plane.

• Opposing Joint Action: Internal Rotation
• Plane of Motion: Transverse (Horizontal) Plane
• Direction Bias: Outward
• Note: Joint actions may be referred to as "osteokinematic motions" or "osteokinematic joint actions" to differentiate them from "arthrokinematic motions " (e.g., spin, glide, roll, compression, and distraction).

For more (including a video lecture), check out:

• Lesson 3: Joint Actions

Joints that Perform External Rotation (and Sample Exercises):

1. Shoulder joint (Glenohumeral joint): External rotation occurs when the humerus rotates so that the anterior surface rotates away from the midline, as observed during shoulder external rotator activation .
2. Hip Joint (Pelvifemoral Joint): External rotation happens when the femur moves so that the anterior surface of the thigh rotates away from the midline, as observed during the goniometric assessment of hip external rotation range of motion (ROM) .
3. Knee joint (Tibiofemoral joint): While subtle, external rotation can occur when the knee is bent. This happens when the anterior surface of the tibia (shinbone) rotates away from the midline of the body relative to the femur. This is observed during the Overhead Squat Assessment and the sign "Feet Turn Out ."