A right posteriorly rotated ilium will cause which of the following?

• A. The left leg to appear longer in long sitting
• B. The right leg to appear longer in long sitting
• C. The right leg to appear shorter in long sitting
• D. The left leg to appear shorter in long sitting

Answer: (A)

A right posteriorly rotated ilium refers to a positional change in the pelvis, which can affect the alignment of the lower extremities. When the right ilium rotates posteriorly, it can lead to changes in the orientation and position of the acetabulum (hip socket) and the femur within the hip joint.

In long sitting, where a person is seated with their legs extended in front of them, this pelvic position causes the right leg to internally rotate, which may make it appear shorter due to the angulation and alignment of the knee and ankle joints. Conversely, the left leg experiences relative external rotation and may lengthen out compared to the right leg.

This mechanical advantage can cause the left leg to seem longer in comparison to the right leg during long sitting. As the right ilium moves posteriorly, the left side compensates, leading to this perceived difference in length. This difference contributes to the overall appearance that the left leg is longer while the right leg may appear shorter from this specific seated position.

Understanding this relationship helps clarify the impact of pelvic positioning on lower extremity alignment and aids in evaluating posture and symmetry in clinical practice.