If a seated flexion test is positive on the right and the sacral base is shallow with the ILA also shallow on the dysfunctional side, what is the diagnosis?

If a seated flexion test is positive on the right and the sacral base is shallow with the ILA also shallow on the dysfunctional side, what is the diagnosis?

• A. Posterior torsion
• B. Anterior torsion
• C. Left unilateral shear
• D. Bilateral torsion

Answer: (A)

The finding pattern is telling us the right sacroiliac joint is the one dysfunctional. When a seated flexion test is positive on one side, the dysfunction localizes to that same side. If both the sacral base and the ILA are shallow on the dysfunctional side, that points to a posterior torsion on that side—the sacrum is rotated backward around an oblique axis, with posterior orientation of both the base and the ILA. So, with a positive result on the right and both landmarks shallow on the right, the diagnosis is posterior torsion on the right. The other forms don’t fit this exact pattern: anterior torsion would show an anteriorly oriented base (not shallow) and a different ILA pattern; unilateral shear involves a different alignment of base and ILA; bilateral torsion would present with changes on both sides rather than isolated to the right.

The finding pattern is telling us the right sacroiliac joint is the one dysfunctional. When a seated flexion test is positive on one side, the dysfunction localizes to that same side. If both the sacral base and the ILA are shallow on the dysfunctional side, that points to a posterior torsion on that side—the sacrum is rotated backward around an oblique axis, with posterior orientation of both the base and the ILA. So, with a positive result on the right and both landmarks shallow on the right, the diagnosis is posterior torsion on the right. The other forms don’t fit this exact pattern: anterior torsion would show an anteriorly oriented base (not shallow) and a different ILA pattern; unilateral shear involves a different alignment of base and ILA; bilateral torsion would present with changes on both sides rather than isolated to the right.