Long Sitting Test (Supine to Sit): Checking Pelvic Rotation

The Long Sitting Test, also known as the Supine to Sit Test, is a functional test used to diagnose sacroiliac joint dysfunction. By observing changes in leg length during movement, it identifies if the hip bone is rotated anteriorly or posteriorly.

1. Purpose

The primary purpose of the Long Sitting Test is to **assess the sacroiliac joint** for functional leg length discrepancies caused by pelvic torsion. It helps differentiate between:

• Anterior Innominate Rotation: The hip bone is rotated forward.
• Posterior Innominate Rotation: The hip bone is rotated backward.

2. How to Perform

1. The patient lies in supine (on their back).
2. The patient performs a bridge (lifts hips up and down) to reset the pelvis into a neutral position.
3. The examiner passively extends the legs and assesses the position of the medial malleoli (ankle bones) to determine which leg is shorter or longer in supine.
4. The patient is asked to sit up (into long sitting).
5. The examiner assesses the position of the medial malleoli again in the sitting position to see if the relationship has changed.

3. Positive & Negative Sign

Positive Sign (Dysfunction Present):
Look for the change in the affected leg:

• Anterior Rotation: The leg appears LONG in supine and becomes SHORTER in sitting (Long to Short).
• Posterior Rotation: The leg appears SHORT in supine and becomes LONGER in sitting (Short to Long).

Negative Sign (Normal):
There is no significant change in the relative leg lengths between the two positions.