Sacroiliac Joints Study

AP Projection

1. Patient in supine position;
2. Lower limbs in extension.

Central ray angled 30-35º cephalad to the middle between Anterior Superior Iliac Spine (ASIS) and pubic symphysis.

Respiration: Suspended.

Evaluation Criteria:

• Lower spine in the center of the image and centered with the sacrum;
• Good visualization of the sacroiliac joints and L5;
• Appropriate exposure values (visualization of the all bony trabeculation and soft tissue).

AP Oblique Projection

1. Patient start in prone supine position;
2. Elevation from the affected side 25-30º

                              - LPO to demonstrate the right joint;
                              - RPO to demonstrate the left joint.

Central ray perpendicular to the middle between Anterior Superior Iliac Spine (ASIS) and pubic symphysis, of the affected side.

Respiration: Suspended.

Evaluation Criteria:

• Sacroiliac joint open and in the center of the image;
• Iliac crest almost in profile position;
• Appropriate exposure values (visualization of the all bony trabeculation and soft tissue).

RPO- Left joint