Babeh Edi

Spine Sacro Iliac Joints AP Oblique

Indications for imaging Trauma, pain. Anatomy  Demonstrated Sacro iliac joint. (Raised side in posterior oblique position) Sacro Iliac Joints AP Lt Posterior Oblique Anatomy Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy Saunders, London Basic Patient Position The examination may be performed either prone or supine, supine will be described here prone is shown by way of comparative example) In the supine position the joint space on the raised side is visualised. The patient lies supine on the table midline in line with the midline of the table, from this position the patient is rotated so the affected side is raised and the midsaggital plane is at an angle of 30 degrees from horizontal, and the patient supported on radio lucent pads. Sacro Iliac Joints PA (RPO) & AP (RAO) Oblique Patient Position Meschan, I. 1955 An Atlas of Normal Radiographic Anatomy Saunders, London Radiation protection There are many local rules for gonad protection however the following should be taken into account. The 28 day rule should be applied for female patients. In males direct lead rubber gonad protection can be applied at all times Central Ray The vertical central ray is directed to a point one third of the distance from the raised ASIS to the patient's midline. Cranial inclination of up to 15 degree may help demonstrate the inferior joint space more clearly. Exposure is made on suspended expiration. Exposure Factors Kv mAS FFD (cm) Grid Focus AEC Cassette 85 60 100 Yes Broad Yes 18 x 24 cm Evaluation of the Image ID and markers must be present and correct in the appropriate area of the film Evidence of collimation on four sides equally around the centering point. Optimal exposure should penetrate all the bone structures and contrast should be low enough to visualise fully the bone and soft tissue structures. Limits of the examination, the SIJ.  Sacro Iliac Joints AP Oblique (LPO) Radiograph (inferior limits missed off!) Related Projections SIJ PA Additional modalities CT MRI